Honda CB500X

Main CB500X Boards => Maintenance and Servicing => Topic started by: fabio on April 22, 2015, 08:06:25 PM

Title: reducing jerkiness
Post by: fabio on April 22, 2015, 08:06:25 PM
I found my bike to suffer from some jerkiness when re-opening gas after it was completely released (what is sometimes called "on/off" effect).
I'm not saying it's something so bad, neither specific to the CB, since almost all modern electronic injected bikes suffer from some on/off.
However, I always try to reduce the on/off in my bikes as much as possible, since it really bothers me especially when riding with cold weather and bad asphalt conditions.
I think the best solution would be adding some electronic stuff like dynojet, but most times I was ok by simply rising engine idle (slightly), may be rising it about 100rpm.
The problem is: HOW can you adjust idle???? There is no screw for idle adjustment and no info in the user manual!!
(SERVICE MANUAL owners: does service manual say anything about idle tuning???)
Title: Re: reducing jerkiness
Post by: Triplebrew on April 22, 2015, 09:39:11 PM
As far as I know the ECU regulates idle speed using various sensors and parameters so is not adjustable?
Title: Re: reducing jerkiness
Post by: Chippy jon on April 22, 2015, 10:09:04 PM
I would be interested in this on/ off effect answer. My dealer said it was me not being use to the electronic throttle.  :187:
Title: Re: reducing jerkiness
Post by: jsonder on April 22, 2015, 11:47:29 PM
If the idle cannot be adjusted, then, you must be slower and more gentle in letting out the clutch.

Personally, my worst problem is idling towards the garage door as the door opener is SLOWLY raising the door.  I have to alternate between disconnected and just barely dragging (almost disconnected) so that there is a lot of slipping going on.  Alternatively, I could stop and wait for the door to be fully opened, but that isn't as challenging. :001:
Title: Re: reducing jerkiness
Post by: EscCtrl on April 22, 2015, 11:54:29 PM
*Originally Posted by fabio [+]
I found my bike to suffer from some jerkiness when re-opening gas after it was completely released (what is sometimes called "on/off" effect).
I'm not saying it's something so bad, neither specific to the CB, since almost all modern electronic injected bikes suffer from some on/off.
However, I always try to reduce the on/off in my bikes as much as possible, since it really bothers me especially when riding with cold weather and bad asphalt conditions.
I think the best solution would be adding some electronic stuff like dynojet, but most times I was ok by simply rising engine idle (slightly), may be rising it about 100rpm.
The problem is: HOW can you adjust idle???? There is no screw for idle adjustment and no info in the user manual!!
(SERVICE MANUAL owners: does service manual say anything about idle tuning???)

Two things that helped me.

1)Adjust chain slack.Sometimes chain whip from a slack chain can cause a similar issue.

2)Adjust the throttle cable so there is very little play.

This helped mine but didn't completely eliminate it.

The only way to set the idle is through an add on unit.Anything done to adjust the idle could result in performance problems.
Title: Re: reducing jerkiness
Post by: Defender on April 23, 2015, 12:04:55 AM
If it only happens noticeably in 1st gear, sprocket change will alleviate it, I have found.
Title: Re: reducing jerkiness
Post by: EscCtrl on April 23, 2015, 01:25:21 AM
*Originally Posted by Defender [+]
If it only happens noticeably in 1st gear, sprocket change will alleviate it, I have found.

Which sprocket and what size?
Title: Re: reducing jerkiness
Post by: Defender on April 23, 2015, 03:11:35 AM
I went to 39T on rear sprocket, but using 16T on drive sprocket has same effect but doesn't require chain to be shortened. Posts on this are legion
Title: Re: reducing jerkiness
Post by: Nortoon on April 23, 2015, 03:38:19 AM
When I first had my CB500 I found it jumpy in first gear because of the quick acting fuel injection and close ratio transmission. It took a while to learn to feather the clutch in first gear, so slow speed maneuvers could be done smoothly.

There is no magic fix, just a skill that has to be practiced and mastered.

When down gearing for city intersection turns, I would suggest using second gear to smooth things out. That is the primary reason I bought a digital gear indicator.

Title: Re: reducing jerkiness
Post by: incolx on April 23, 2015, 08:24:09 AM
As reported in another thread, the quick and easy answer to this is to add a little play to the throttle cable.  I did this very soon after picking up the bike and it works so well I hadn't thought about it for ages.

The extra play takes care of any involuntary twitches of the wrist.
Title: Re: reducing jerkiness
Post by: Harry on April 23, 2015, 09:58:20 AM
While in 1st gear slipping the clutch is the recommended method with low speed manoeuvres etc... from there on up I've found riding in one gear too high helps a great deal.
Our roads here are still very damaged from earthquakes so riding in a higher gear makes the bike less responsive.
Otherwise good posture control is key, use your legs, your stomach and back muscles so that your wrists are not affected.
Title: Re: reducing jerkiness
Post by: sarcaster on April 23, 2015, 07:17:00 PM
*Originally Posted by incolx [+]
As reported in another thread, the quick and easy answer to this is to add a little play to the throttle cable.  I did this very soon after picking up the bike and it works so well I hadn't thought about it for ages.

The extra play takes care of any involuntary twitches of the wrist.

Being a new rider, can you give detail on how to do this?  And maybe some detail on why this might help?  Thanks.
Title: Re: reducing jerkiness
Post by: EscCtrl on April 24, 2015, 03:46:21 AM
*Originally Posted by incolx [+]
As reported in another thread, the quick and easy answer to this is to add a little play to the throttle cable.  I did this very soon after picking up the bike and it works so well I hadn't thought about it for ages.

The extra play takes care of any involuntary twitches of the wrist.

I tightened mine up.I wasn't getting the resistance because of the loose cable and it made me twitchy on the throttle.Everyone reacts to this differently.Mine was to twist faster until I had the resistance which lead me to lurching the bike at low speeds in first gear with the clutch lever out.


*Originally Posted by sarcaster [+]
Being a new rider, can you give detail on how to do this?  And maybe some detail on why this might help?  Thanks.

The two cables at the throttle block.One has a thick rubber cover over it.Push the rubber cover back.There is a long barrel nut and a small regular nut.The regular nut is a lock nut.Loosen it.Then adjust the barrel nut until you have the slack or tightness that you want.Tighten the lock nut when you have it set,and slide the rubber cover back over it.

Here it is on a CBR.It the same on our CB-X.
Title: Re: reducing jerkiness
Post by: fabio on April 24, 2015, 12:19:19 PM
Sincerely I do not think that playing with throttle adjustment could be the solution.
In my bike at least, throttle play is ok.
The problem is some DELAY between the throttle re-opening and the traction of the wheel that always starts rough after some (unpredictable) delay of some cents of second.
Yes the first thing I will now try to do is to tighten the chain and let you know.
I also wonder whether valve adjustment (which was NOT done on my bike at first service, the bike being produced in 2014) could be related with jerkiness or not.
Title: Re: reducing jerkiness
Post by: C-rider on April 24, 2015, 04:08:37 PM
Sorry that I cannot offer any solutions to anyone who is having this problem.  I was just thinking yesterday how this is one of the great things about this bike: perfect fuelling and lack of drive line snatch.  I can't fault mine.  It makes it so easy and pleasurable to ride.  None of that urgency to shift up to the next gear to get out of an unpleasant rev range.  I can enjoy just tooling around neighbourhoods in 2nd or 3rd gear at almost any engine speed.  There really seems to be no sweet spot. They are all sweet.  I have 10000km on mine now with original chain and sprockets.  Chain slack is normal.   
Again I can't offer anything but hope.  The truth is out there and worth pursuing.
Title: Re: reducing jerkiness
Post by: fabio on April 24, 2015, 04:21:17 PM
C-rider I don't get the point of your post...
we're happy to know everything is fine with your bike and you're in love with it!
however, my bike's chain play is already more than 4.5cm after only 7,000km and less then a year, so it * MAY * be the cause of my bike's jerky behavior in reopening gas (I'll let you know as soon as I will ride it, since I already tightened the chain play to about 3,5cm).
However I'm not so confident this will change things dramatically, but I could be wrong.
Title: Re: reducing jerkiness
Post by: motorboy on April 24, 2015, 04:38:11 PM
His point is he likes his bike and just wants to share nothing wrong with that--and I think after you ride yours with the chain in spec you will notice the different.  I have had bikes that jerk on take off but my 500 is not one of those very smooth all most to smooth. I see some members are saying less slack in the throttle cable, some say more slack I'm in the camp of less slack(2mm) makes for a smoother ride also clutch cable slack as per manual 20mm
Title: Re: reducing jerkiness
Post by: EscCtrl on April 24, 2015, 04:42:36 PM
*Originally Posted by fabio [+]
Sincerely I do not think that playing with throttle adjustment could be the solution.
In my bike at least, throttle play is ok.
The problem is some DELAY between the throttle re-opening and the traction of the wheel that always starts rough after some (unpredictable) delay of some cents of second.
Yes the first thing I will now try to do is to tighten the chain and let you know.
I also wonder whether valve adjustment (which was NOT done on my bike at first service, the bike being produced in 2014) could be related with jerkiness or not.

2014 and later bikes do not require a vavle adjusment until 16,000 miles/25,600km.

(https://images.weserv.nl/?url=ssl:farm9.staticflickr.com/8684/17010988021_6f0d39ae41_z.jpg)
Title: Re: reducing jerkiness
Post by: Tjn on April 24, 2015, 05:02:56 PM
*Originally Posted by fabio [+]
C-rider I don't get the point of your post...
we're happy to know everything is fine with your bike and you're in love with it!
however, my bike's chain play is already more than 4.5cm after only 7,000km and less then a year, so it * MAY * be the cause of my bike's jerky behavior in reopening gas (I'll let you know as soon as I will ride it, since I already tightened the chain play to about 3,5cm).
However I'm not so confident this will change things dramatically, but I could be wrong.

Just for the record ,
That was my chain play at 1000 km, (4.5).  I could have gas jerkiness too, which is why I change gears, at 3 or 4k RPM. I'm at 2500 km, and I have to adjust one more time.  Being my first bike, To me all this is normal, nothing feels too unpleasant.
Title: Re: reducing jerkiness
Post by: fabio on April 24, 2015, 05:19:45 PM
In my experience it's not so common: I rarely had to adjust chain play in all my previous bikes! No more often then every 10,000km... may be cbx chain is a bit "weak
Title: Re: reducing jerkiness
Post by: tango19 on April 24, 2015, 05:23:42 PM
Fabio,
 I , and probably many others adjusted the chain around 1000km, you are correct the chain is not the best quality.
There has been much written on here about chains.  :002:
Title: Re: reducing jerkiness
Post by: EscCtrl on April 24, 2015, 07:09:20 PM
*Originally Posted by tango19 [+]
Fabio,
 I , and probably many others adjusted the chain around 1000km, you are correct the chain is not the best quality.
There has been much written on here about chains.  :002:

I did at 600 miles/1000km.It was barely tight enough from the factory.I assume,this was to allow for break in of the drive train and help prevent over stressing the rear cush drive and transmission.Since adjusting it,I haven't needed to touch it again.It seems to be staying within spec for adjustment.I lube the chain everys other fill up.I'm planning a DIY chain oiler.
Title: Re: reducing jerkiness
Post by: Grim Rider on April 24, 2015, 08:23:19 PM
When I was instructing used to see a lot of jerkiness on bikes; usually it could be fixed by removing the jerk from the bike  :001:
Title: Re: reducing jerkiness
Post by: grnd0 on April 25, 2015, 01:56:09 AM
*Originally Posted by Grim Rider [+]
When I was instructing used to see a lot of jerkiness on bikes; usually it could be fixed by removing the jerk from the bike  :001:


 :745:  :008:
Title: Re: reducing jerkiness
Post by: crisb on April 25, 2015, 03:26:56 AM
As the X is my first bike, I've developed my riding style in its image. I did find the jerkiness a bit tricky to start with, but judicious use of clutch seems to deal with most of it. I also find also that as it's only the initial application that grabs (thereafter it's smooth), making sure that on tight slow bends I've always taken that up whilst still bolt upright, ie. before any lean, reduces how often I reach for the clutch. I hope that isn't setting me up with poor habits to unlearn on other bikes.


*Originally Posted by Grim Rider [+]
When I was instructing used to see a lot of jerkiness on bikes; usually it could be fixed by removing the jerk from the bike  :001:

I think quite a few such jerks are efficient at self-removing.

Title: Re: reducing jerkiness
Post by: Freeflow on April 25, 2015, 09:03:06 PM
It's better to remove the jerk behaviour from the rider.  A big stick may help.

I've not noticed much in the way of jerking from mine, my 900 Hornet was apalling when I first got it and I had a Power Commander fitted [BSD near Peterborough] which smoothed things out, gave 4 bhp [4% more power over standard] and better fuel economy as well.  No exhaust or airbox mods were carried out.

The jerkiness can be sorted by technique on a bike with fuel injection from standard.  The 900 Hornet is a 919 'blade engine that was designed for carbs but running under fuel injection, most bikes like this suffer from 'on-off' throttles, although my XJR1300 didn't.

Rather than adjusting the throttle to remove the free play, or indeed to give you more 'slack' try to feel where the throttle starts to pick up, with the engine off you can find this by opening the throttle to the point where the slack vanishes and it feels like you are opening the slides.  With the engine on it's when the revs pick up.  You can adjust your hand position so that you let the throttle go onto the tickover position without getting lots of slack into the cable that you then need to remove by opening the throttle.  This will also position your hand better for control over the throttle position for most speeds you will be at.

The other thing to look at is the clutch.  The Japaneese, not the people with the biggest hands in the world, set the clutch bite point a lot further out than I like-perhaps they think Chewbacca rides their bikes?  If you have small hands you will probably need to adjust the position, mine are 'rubber glove size' 8 1/2 and I need my lever bringing in about 5mm on every bike I've owned.  Being able to feather the clutch also makes slow riding a lot easier.  If you put the bars into a right hand turn to the stop and your hand can't hold the clutch at the bite point try adjusting it.  If you aren't confident riding with the bars against the stop then do it while stationary.

Think about when you feel the jerkiness-pulling off from a stop [hand postion may help], slow riding in traffic [clutch may help], changing gear [being smoother, and picking a different engine speed may help]?

Also, think about planning ahead.  If you need to constantly react to traffic slowing by closing your throttle try leaving a bit more of a gap for you to "ride into" while slowing, that way you may reduce your need to close the throttle fully or brake and be smoother.
Title: Re: reducing jerkiness
Post by: Grim Rider on April 25, 2015, 10:33:45 PM
Try not using the clutch - apart from going into 1st I rarely use mine for up or down changes; and have only once had to change a clutch (due to oil contamination from a leaking oil seal) in 30 years of riding.
Title: Re: reducing jerkiness
Post by: incolx on April 25, 2015, 10:56:55 PM
I think this thread's got totally out of hand.  The basic problem is rather crude fuelling, meaning that a very small throttle movement can result in the application of a disproportionate amount of power, ie 5% opening results in, say, 10% power.  No amount of chain adjustment (if within the normal range) will make any difference, other than risking damage to chain/sprockets/bearing, as somebody else's noted.  How could changing sprocket ratios make any difference?  Changing gear without using the clutch is something I've tried but I can't really see any point in it.  This problem is caused by snatch when already in gear.

When I first got the bike, I found the ride quite jerky till I had the idea of adding a little play to the throttle cable, which allowed a bit of involuntary rotation without applying unwanted power.  Slipping the clutch can also help when negotiating tight turns, etc.

I also fitted a bar brace, which reduced the spring in the bars over bumps and further helped to keep the ride smooth.
Title: Re: reducing jerkiness
Post by: Grim Rider on April 25, 2015, 11:06:00 PM
That is one way of looking at it incolx -  another is that it has developed organically as people carry on the conversation. But keep on telling us to adjust the throttle cables if you feel it necessary. The point of changing gear without using the clutch, apart from not wearing the he clutch out, is that it teaches you mechanical sympathy and an understanding of how to control the bike without having to keep slipping the clutch,
Title: Re: reducing jerkiness
Post by: Defender on April 25, 2015, 11:53:04 PM
Changing sprockets makes for a higher 1st gear thus making a less fierce take up without need to slip the clutch. 1st was the only gear I had the snatch throttle problem with, but changing the sprocket put all the other ratios in a better range. I did it, and it worked for me. Doesn't really matter if anyone else believes it, I have the empirical evidence of it's efficacy. As I always say though, it won't suit everyone.
Title: Re: reducing jerkiness
Post by: incolx on April 26, 2015, 08:13:18 AM
I can see I'm wasting my breath and others are intent on wasting their money on stuff that has no relevance to the issue of snatch-whilst-in-gear (any gear) due to involuntary wrist movement and an over-sensitive throttle.  I'll shut up now.
Title: Re: reducing jerkiness
Post by: motorboy on April 27, 2015, 04:44:01 AM
It looks like to me you got some good answers   not sure what you wanted to hear  I think your best bet(and it will work) is to put higher gearing as stated by members 1 up on counter or 2 down on rear WILL get rid of the jerking
Title: Re: reducing jerkiness
Post by: X-Centric on April 28, 2015, 10:23:30 AM
I disagree, if someone has a problem the they have a problem, the fact that other people don't have a problem or have found ways to address it, isn't an answer. Forums are here to help people who have problems, it should be what we are here for.

I can exactly identify with the problems some people are having, the inability to dial in a small throttle opening from a closed throttle.

Defenders answer was to fit a 39T rear sprocket, and I have no doubt that will help as 1st and 2nd gear are low (a bit too low IMHO), and correctly adjusting throttle cable slack will also no doubt help.

Personally I don't find the throttle response that bad, but there are times on a bumpy road when I do find it a bit snatchy.

I would add 2 comments:

1) fitting grip puppies over the standard grips increases the diameter of the throttle grip which not only makes the action lighter but allows greater precision when opening a closed throttle. I found it helped quite a bit. Worth a try and cheap, but don't help much if you have heated grips.

2) Changed my chain and sprockets last weekend, the stock gearbox sprocket had a little play on the splines, I replaced it with a JT sprocket which was a perfect fit. I think this has also helped a bit, but as I also fitted a new chain and rear sprocket (Standard 41T) at the same time it's difficult to judge, but it can only have helped. Gear change is better now though.
Title: Re: reducing jerkiness
Post by: Randomsquid on April 28, 2015, 05:45:42 PM
I had three problems that were contributing to the jerks.

The bike is under geared but now that I have some miles on the engine I just ignore 1st unless coming to a dead stop.

Too much free play in the throttle, about a cm, now adjusted to something more normal. This was the biggest issue.

The back shock was under damped in much the same way as a pogo stick is. That's settled down now that it's bedded in.
Title: Re: reducing jerkiness
Post by: Freeflow on May 12, 2015, 09:23:10 PM
I don't agree with the comment about crude fuelling, I find that I don't get any jerkiness unless I try to go from on throttle to off then back to a wider setting quickly, this will produce jerkiness on any bike.

I find the 'X' to be well set up in the engine department with a flatter torque curve [seat of pants rather than dyno] than my '99 CB500 and certainly no more jerky than the carbs on the slightly more powerful but far older bike.  The bikes I have owned over 30 bhp [GPz305, CB500, 955i Speed Triple, 900 Hornet, XJR1300, CB500X] have all been smooth apart from the Hornet.

I would still argue that better throttle and clutch control will sort out most problems, and if my 900 Hornet was the only bike I rode I would have adapted to the really jerky ride over a few months, but it wasn't and I had to go for a technical solution.
Title: Re: reducing jerkiness
Post by: MichaelCM on December 22, 2016, 06:29:47 PM
Obviously the most likely reason for jerky throttle response is the operator, but I was giving my pillion whiplash!

I had the right hand side cover off looking at throttle freeplay ( there was not any adjustment left at the handlebars to slacken the cables) and decided to lubricate where the cable goes around the quadrant.

Great result! Much more progressive at low speed. The area is easily accessed but vulnerable to road grime so worth checking.

Title: Re: reducing jerkiness
Post by: CB-500-X on December 22, 2016, 06:44:52 PM
Plus 1 for taking all the slack out of the throttle cable and changing the sprocket th 39 teeth. Took care of all the jerky/twitchyness
Title: Re: reducing jerkiness
Post by: selftaught on December 22, 2016, 07:15:35 PM
I'll add support for the grip puppies. They and my TKC 80 tires are the two things that made me enjoy riding the bike again.

Title: Re: reducing jerkiness
Post by: Matt F. on December 22, 2016, 07:36:36 PM
39T sprocket is one of the best mods I made to my bike.  That jerkiness was a real issue for me.  Now it is little more than a vague memory.
Title: Re: reducing jerkiness
Post by: Britchris on December 23, 2016, 11:14:01 AM
Some thoughts on this issue:
Grip puppies/larger diameter grips give more throttle opening/closing control.This is good.
1st gear is REALLY short on the X. As said previously, ignore it unless you're at a complete stop.This is good.
Dial out the throttle"slack". (My personal preference)
Adjustable levers help w/clutch control.(I'm a 14 stone+/200lb lump with tiny hands)
I'm of the ,"if it ain't broke don't fix it" school of motorcycle ownership. Consequently, I do not see the point of messing with the fuel delivery system by adding anything to the bikes ECM.
Adjust the rear suspension to suit your riding style/weight. (This helped me out a lot.)
Finally: get plenty of low speed riding/maneuvering practice in. (This is always good)

Obviously, YMMV. We are all individuals and no one fix suits all.
Ride safe,
Chris C
Title: Re: reducing jerkiness
Post by: MichaelCM on December 23, 2016, 02:53:18 PM
Just to clarify: The intention of my post was just to inform you all that simply lubricating the throttle quadrant made a HUGE difference to controllability. I did nothing else, just the lube.

I have just returned from an evening in the city threading my way between cars, trucks and busses at low speed and believe me, it behaves like a different bike.
Title: Re: reducing jerkiness
Post by: CB-500-X on December 23, 2016, 03:19:29 PM
Good to know , thank you.
Title: Re: reducing jerkiness
Post by: selftaught on December 23, 2016, 03:45:57 PM
What did you use as lubricant?
Title: Re: reducing jerkiness
Post by: MichaelCM on December 23, 2016, 09:10:28 PM
*Originally Posted by selftaught [+]
What did you use as lubricant?


I used a WD40 type spray with extension tube to clean out the groove, then a light oil. Probably a non sticky lube would be better though as the oil will tend to trap dust again.
Title: Re: reducing jerkiness
Post by: wardie on January 23, 2017, 04:13:36 PM
Check tension on chain. That's the usual suspect and first place to check.

Second is the chain and/or sprockets worn?

Third the rear sprocket dampeners check them for wear.
Title: Re: reducing jerkiness
Post by: Hotrod on April 18, 2018, 05:21:32 PM
I have also found the x to be quite jerky, even when going through the gears whilst on the main stand without load,  at first I thought it was due to the recommended 35 to 45 mm chain slack needed for the suspension travel,  but then it is fairly erratic even when trying to hold it at a steady rpm when in neutral throughout the Rev range compared to most bikes that I've owned,  maybe we're asking a little too much from an inexpensive gorgeous little bike ?
Title: Re: reducing jerkiness
Post by: Superplasma on April 20, 2018, 09:36:12 AM
For me bring back the Carbs, never had this problem with them.

Superplasma.
Title: Re: reducing jerkiness
Post by: Hotrod on April 20, 2018, 11:16:57 AM
Yes i must agree with you on the carburettors, they have nice n simple internals with less technology to go wrong,  equals easy maintenance and D I Y repair if necessary,  happy days
Title: Re: reducing jerkiness
Post by: AJC500 on April 20, 2018, 04:47:23 PM
Just been out for the afternoon - throttle smooth as silk - the bike is quite new/low mileage/just serviced, maybe that's why?  Or maybe I'm just a smooth rider.......hmmmmm!!  :153:
Title: Re: reducing jerkiness
Post by: Lattugo on April 20, 2018, 06:22:58 PM
Honestly I find the CBX pretty smooth and I must say no on/off effect on my bike.

I experienced very bad on/off on my previous one though, 2000 Honda Hornet 600 (carbs), when idle was too low.
What is good with carbs, is that you can adjust the idle and there is less thing that can breake, but on the negative side I needed to spend a good 3 to 5 minutes every morning at the first fire to gently convince the engine to rev properly  :008:
Title: Re: reducing jerkiness
Post by: Hotrod on April 20, 2018, 07:04:13 PM
Even when you gently increase the revs and hold them steady at  2  3 and 4000 + rpm without load for example in neutral ?  because if the revs deviate when you're doing that test,  surely you'll notice that when out for a gentle ride on a level road,  but then saying that  Most of the motorists that i see on the road accelerate and decelerate hard and never notice any fluctuation in the engine's performance anyway so it probably doesn't bother them,  just my humble opinion so please don't sentence me to life  :431:
Title: Re: reducing jerkiness
Post by: SnowOwl on April 20, 2018, 07:26:59 PM
No carbs for me!  I'm done with that mess.  I love being able to fire up the bike in any weather, hot or cold, and just riding off.  No messing with a choke and no challenge to get moving until it warms up.  I park my bike in my basement and with fuel injection I can start it in the basement in the morning and ride out without stinking up the entire house.  Another big plus with FI is the substantially better gas mileage which is one of the strong points of this bike.
Title: Re: reducing jerkiness
Post by: HCCI on December 29, 2018, 10:38:52 PM
*Originally Posted by Hotrod [+]
Even when you gently increase the revs and hold them steady at  2  3 and 4000 + rpm without load for example in neutral ?  because if the revs deviate when you're doing that test,  surely you'll notice that when out for a gentle ride on a level road,  but then saying that  Most of the motorists that i see on the road accelerate and decelerate hard and never notice any fluctuation in the engine's performance anyway so it probably doesn't bother them,  just my humble opinion so please don't sentence me to life  :431:
Hello.
Your opinion is spot on with what it feels on my bike, Below 2200 RPM on flat road, the engine is going to shake but strangely it might not happened if going uphill. I find myself a lot of times downshifting one gear on the flat portion of a road after going uphill with a taller gear just moments before. This sounds like a defective TPS i know but mine has been tested and it is fine. When new, the bike did shake but it was at lower speed, around 51 KM/h in 6th gear but now after 21000 Ks it happens at 55 km/h. For me it seems there is a flat spot when going from idle up to a certain throttle opening that causes this. It is throttle position related more than anything else. People pushing the bike harder might not even notice this but those seeking for frugality will hit a wall every time the throttle will reach a certain aperture just where the flat spot begins. Carburetors had a series of small holes along the course of the throttle plate from closed to avoid this.
Title: Re: reducing jerkiness
Post by: Phil80 on December 29, 2018, 10:58:04 PM
Guys,
After giving up my 500x earlier this year, I know your thoughts on the jerkiness- i found it worse round town. When i got my ktm i found a similar thing. When i started looking into it it seems (on the ktm) has 2 maps a really lean one for emissions unto about 4k rpm then switches to a better fuelled map, this is to meet euro 3 standards.

This lean map made town riding horrible, surging, slight chugging when backing off and manoeuvring near idle. Some people had fitted o2 eliminators - which, by passes the o2 sensor with a plug - in this plug are resistors of a certain value to get an adequate fuel value being injected.
For me this made a huge difference, i was sceptical but thought 20 for mine was worth a punt, worked for me.

I think it maybe worth trying for you guys that don't like the jerkiness. Cant say its affected my mpg either.

https://www.ebay.co.uk/p/Oxygen-Lambda-O2-Sensor-Eliminator-Kit-Honda-CB-500-F-X-Cb500f-Cb500x/8020159215

Regards
Title: Re: reducing jerkiness
Post by: Jonathan on December 30, 2018, 02:29:28 AM
Most modern FI bikes are on the lean side in stock form, but it's something you can usually work round with lowered gearing or a bit of clutch slip. Not had a look, but I'm assuming there's a power commander or similar available for the CB range by now. How much an O2 bypass would affect the Cat long term would be good to know...

The other thing to consider is the throttle action itself, if you don't fancy tweaking factory fueling. Having a bit of twist resistance isn't such a bad thing.

I don't notice any snatchiness on my 2016 (stock filter & exhaust) but for 20 it'd be interesting to see if there's any improvement in general pick up.
Title: Re: reducing jerkiness
Post by: ThirtyOne on December 30, 2018, 02:47:05 AM
*Originally Posted by Jonathan [+]
Most modern FI bikes are on the lean side in stock form, but it's something you can usually work round with lowered gearing or a bit of clutch slip. Not had a look, but I'm assuming there's a power commander or similar available for the CB range by now. How much an O2 bypass would affect the Cat long term would be good to know...

There are. And a grip of gents over on the CBR500R forum have apparently cracked the ECU open and are navigating custom maps. Oyabun is also going to work in his lab as we speak.
Title: Re: reducing jerkiness
Post by: CaptCapsize on December 30, 2018, 05:04:24 PM
You could try a G2 Throttle Tamer.  It is a throttle tube with a cam change for reducing the initial cable pull.  It made an huge difference on my WR450F.  It is geared low and has a lot of initial power.  It was very jerky in rough terrain which caused me a lot of grief/pain.  Check it out.
 
https://www.revzilla.com/motorcycle/g2-throttle-tamer-honda
Title: Re: reducing jerkiness
Post by: Mister Paul on December 31, 2018, 08:52:47 AM
Jerkiness is a rider issue. I admit that coming to my second X from a scooter it did feel overly jerky. A few months of riding later and it's jerk-free. It's all about wrist action.
Title: Re: reducing jerkiness
Post by: Jonathan on December 31, 2018, 07:06:11 PM
just had an email back from a guy named Jens Lyck,in Denmark, who's a bit of a whizz with Fuel Injection, programming etc. He personally wouldn't recommend ditching the O2 sensor on the CB 500 range, for several reasons. The preferred method to richen the mixture is to 'fool' the Air intake Temp. sensor into thinking it's colder than it actually is, but if you used a straightforward linear NCT resistor to achieve this, it doesn't take the actual temperature into account...so on a hot day, you could end up running massively rich. In short, you'd want a resistor that trims the air intake temp with some form of monitoring to 'switch' it on or off. He's developed a plug and play unit that does just this, but according to Jens, Honda integrated the IAT sensor with other feedback sensors in such a way that it's practically impossible to isolate and tweak the sensor in question.

Simply removing the O2 sensor will richen the mixture up since the ECU will see a lean condition and alter the Air/Fuel ratio accordingly, but it only does this during the times it's actually relying on feedback from the O2 sensor (eg. steady throttle, cruising speeds), which isn't really when you'd need a richer mixture...the net effect would be to reduce mpg.

The O2 sensor eliminators currently available for the X are the small resistor type that send the correct signal to the dash to prevent a fault code, but don't take any account of the intake air temperature....so richer throughout the entire range (up to the limits set by the ECU software), whether it's required or not. So it may reduce jerkiness off idle (desirable), but add fuel at cruising (not really desirable).

He looked into developing a product for the CB 500 range a while ago, but didn't take it any further on account of the issues stated earlier.

The long and short of it is that eliminating the O2 sensor will richen the A/F ratio and may cure the snatchiness, but in hotter climates, you may want to think about running hotter grade plugs and using a less restrictive air filter...

If you can achieve the same ends with grip puppies, a throttle damper or whatever, I'd personally try these first


Aftermarket fuel programming would seem like the only nailed-on solution, but as far as I'm concerned, Honda know a damned sight more about it than me, and unless you've deviated from stock with different throttle bodies, cams, compression ratio, etc. I don't see the point on this bike.
Title: Re: reducing jerkiness
Post by: SnowOwl on December 31, 2018, 08:38:43 PM
 :460:  The physical design of this engine is one that emphasizes torque and not horse power.  This was done intentionally by Honda to give a bike that performs well but stays within the beginner class licensing restrictions for the countries that have those restrictions.  It is not a high performance sport bike and cannot be made into one due to the physical dimensions of the bore/stroke, crankshaft and gearing.  Sure, you can spend a lot of money and get maybe 10% more out of it, but why not take the original purchase price plus all the extra money to try to make it something its not and buy a bike that is designed to do what you are looking for?
Title: Re: reducing jerkiness
Post by: Oyabun on January 01, 2019, 12:37:06 AM
*Originally Posted by ThirtyOne [+]
There are. And a grip of gents over on the CBR500R forum have apparently cracked the ECU open and are navigating custom maps. Oyabun is also going to work in his lab as we speak.

Well, we're having some progress already - pretty sure we're going to have some nice new maps out this coming year. ;-)
The first head+cams combo is ready to sail out to Canada this week.
Title: Re: reducing jerkiness
Post by: Jonathan on January 01, 2019, 02:38:37 AM
*Originally Posted by Oyabun [+]
Well, we're having some progress already - pretty sure we're going to have some nice new maps out this coming year. ;-)
The first head+cams combo is ready to sail out to Canada this week.

are you using the Power Commander V, or an alternative?
Title: Re: reducing jerkiness
Post by: Oyabun on January 01, 2019, 03:05:01 AM
My current setup is a PCV and a WB2 (wideband lambda sensor and controller) which is connected to both the PCV for autotune, and also provides a simulated narrow band signal what is shifted to 13.8AFR instead of the oem 14.7.
The setup 31 mentions is a different rig. It is essentially a dapsberry PI used to do the autotune function as a road dyno( calculating the difference between a desired AFR map, and the stock fueling) to lrovife input on how to change fuel maps reflashing the stock Honda ECU.
The oem unit is fairly sophisticated, having diferent fuel and ignition maps for the two cylinders, individual maps for 1-2 3-4 and 5-6th gears, same for the rev limiter and such.
Ideallly the end result will be a simple tool which allows reflashing fhe oem computer with specific maps to individual changes. The reading, a d flashing of contents already works, we're currently hacking the oem compuger maps and testing reliability.

P.s. im just loving this little mill. Able to squeeze about 30%more top end power and 40% more mid-range torque is not to be looked down at. Alllways love when smart people of the internet claim that it is lkmiged to negligible improvement only. True, it is not as easy as to put a new akrspovic exbajst system to a cbr1000rr and gaining an instant 14 horsepower boost, but on tbe other hand that extra 14 woulf be only about 6-7% and probably unusable anyway on an insanely powerful liter.bike, while it is a huge improvement on an 500.
Title: Re: reducing jerkiness
Post by: Jonathan on January 02, 2019, 01:13:59 AM
*Originally Posted by Oyabun [+]
My current setup is a PCV and a WB2 (wideband lambda sensor and controller) which is connected to both the PCV for autotune, and also provides a simulated narrow band signal what is shifted to 13.8AFR instead of the oem 14.7.
The setup 31 mentions is a different rig. It is essentially a dapsberry PI used to do the autotune function as a road dyno( calculating the difference between a desired AFR map, and the stock fueling) to lrovife input on how to change fuel maps reflashing the stock Honda ECU.
The oem unit is fairly sophisticated, having diferent fuel and ignition maps for the two cylinders, individual maps for 1-2 3-4 and 5-6th gears, same for the rev limiter and such.
Ideallly the end result will be a simple tool which allows reflashing fhe oem computer with specific maps to individual changes. The reading, a d flashing of contents already works, we're currently hacking the oem compuger maps and testing reliability.

P.s. im just loving this little mill. Able to squeeze about 30%more top end power and 40% more mid-range torque is not to be looked down at. Alllways love when smart people of the internet claim that it is lkmiged to negligible improvement only. True, it is not as easy as to put a new akrspovic exbajst system to a cbr1000rr and gaining an instant 14 horsepower boost, but on tbe other hand that extra 14 woulf be only about 6-7% and probably unusable anyway on an insanely powerful liter.bike, while it is a huge improvement on an 500.

I cut my remapping teeth on Megajolt, after doing a crank-fired ignition conversion on a twin Webber'ed air cooled VW, which seems like child's play compared to meddling with modern FI.

I totally get the notion of taking something stock and seeing what''s feasible, within reason...plenty will say "why not just buy a more powerful bike?" but that's missing the point.  I reckon most X owners would like more power, (especially low-mid range torque) but aren't really prepared to go to the nth. degree, due to the work/expense involved. Like you say, a 10HP increase with an aftermarket pipe and K&N isn't an option, sadly. Good Luck with the developments... :028:

Title: Re: reducing jerkiness
Post by: Superplasma on January 11, 2019, 10:04:13 AM
*Originally Posted by Freeflow [+]
It's better to remove the jerk behaviour from the rider.  A big stick may help.

I've not noticed much in the way of jerking from mine, my 900 Hornet was apalling when I first got it and I had a Power Commander fitted [BSD near Peterborough] which smoothed things out, gave 4 bhp [4% more power over standard] and better fuel economy as well.  No exhaust or airbox mods were carried out.

The jerkiness can be sorted by technique on a bike with fuel injection from standard.  The 900 Hornet is a 919 'blade engine that was designed for carbs but running under fuel injection, most bikes like this suffer from 'on-off' throttles, although my XJR1300 didn't.

Rather than adjusting the throttle to remove the free play, or indeed to give you more 'slack' try to feel where the throttle starts to pick up, with the engine off you can find this by opening the throttle to the point where the slack vanishes and it feels like you are opening the slides.  With the engine on it's when the revs pick up.  You can adjust your hand position so that you let the throttle go onto the tickover position without getting lots of slack into the cable that you then need to remove by opening the throttle.  This will also position your hand better for control over the throttle position for most speeds you will be at.

The other thing to look at is the clutch.  The Japaneese, not the people with the biggest hands in the world, set the clutch bite point a lot further out than I like-perhaps they think Chewbacca rides their bikes?  If you have small hands you will probably need to adjust the position, mine are 'rubber glove size' 8 1/2 and I need my lever bringing in about 5mm on every bike I've owned.  Being able to feather the clutch also makes slow riding a lot easier.  If you put the bars into a right hand turn to the stop and your hand can't hold the clutch at the bite point try adjusting it.  If you aren't confident riding with the bars against the stop then do it while stationary.

Think about when you feel the jerkiness-pulling off from a stop [hand postion may help], slow riding in traffic [clutch may help], changing gear [being smoother, and picking a different engine speed may help]?

Also, think about planning ahead.  If you need to constantly react to traffic slowing by closing your throttle try leaving a bit more of a gap for you to "ride into" while slowing, that way you may reduce your need to close the throttle fully or brake and be smoother.



Top post, 10/10.


Superplasma.