Having Vibration Issues

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Incidentally, re the TBS, I am more interested in curing hesitancy of rev pickup just off tickover when pulling away and transitioning from closed to cracked open throttle when moving slowly.
A throttle body sync isn't going to fix your hesitancy problem. Sorry.

Where IS your "tickover" point? If it's the "as-delivered" 750-800rpm, bumping that up to 1100rpm will deliver the panacea you're looking for. A throttle-spring unwind will also help that transition, because it will be smoothed out greatly by you not having to "fight" that ***** of a spring. :)
I've read elsewhere in the forum reports of cleaner uptake on the throttle after doing a TBS, official and unofficial versions, as well as mixed results re vibration reduction so I'll keep an open mind until I've tried it meself.

Also upped idle revs from 900 to 1100 last week as suggested elsewhere but as yet haven't felt much of an improvement.

As you say, spring unwind should help and also want to do the cable ramp mod. and fit the Grip Buddies.

Time,Time Time.

 
Finally got the Morgan Carbtune and started into it tonight. Found one potential vibration issue right off the bat - the two bolts holding the gas tank down were spinning freely as soon as I put an allen wrench to them. This was the same shop that also emptied a couple gallons of gas from my full tank to do the harness replacement and forgot to put it back. Poor attention to detail, I'm pretty disappointed in them. Had actually driven an hour there cause the shop right down the street did poor work as well. Time to find yet another one.... :dribble:

Did the plugs, did the throttle spring release (that took a little bit of work to get to). Test fired after each time and it was still working, so that's good.

got the TBS all set up and started the bike again. Initial idle had the numbers on the Carbtune where I would have expected them (240-250), but after it idled for a bit and warmed up they shot up between 280 and 300, over what the spec say the range should be. Got them all down into the 260 range (+/- 5) and it seemed to be a lot more relaxed even just idling. Short spin around the block and I must say the takeoffs with the spring change were like butter! Letting off the throttle takes a little getting used to, as it no longer snaps closed quickly, but I can get used to that. Will be interesting to see the difference in wrist fatigue on a long ride.

Still could feel when I got to 2k and 4k on the tach, but was much more muted. Tomorrow I'll have a chance to take it on the highway and see the high speed road manners.

Thanks again to all for the tips and help, working on the bike is very straightforward with all the resources here!

 
Good thread, I did my first TBS last night with the Motion Pro (yea, yea) Did a quick

order, and it was here. Then I read thread about the Morgan piece, well...I have seen

folks build their own, and swore by it, but my results were:

Synced the Tool first.

Initial hook up to the TB's found them to be not in sync..shocking right?

Synced all to the #3, as the tech pages stated. Although I printed the "Unauthorized Method"

I did not use it, maybe on the next sync.

Went for a 3hr ride today, and the difference was there.

*No buzz on the bars, and no numbing of the hand.

*Really could feel the smoothness between acceleration 3k-5k

*Bike felt lighter, probably because I wasn't gripping as tight when accelerating.

*First 1/4 tank yielded a bit better gas mileage..registering low 40, before 36.

*Because it was smoother, it gave more confidence in handling.

The tool was easy to use, and to me did what it was supposed to do. I didn't

think the results would be as obvious as they were, but it was.

 
UPDATE:

I did the standard TBS, that was of moderate help but not as much as I was hoping. Today I was back in the bike and went ahead and did the advanced TBS to see the difference (using the instructions on the Bin O Facts page). I had to make adjustments to all 3 of the butterfly screws to get them on all par. It could be because I'm close to 18k and have never done this before, but it seemed to make a more significant difference than the standard for me. Next time, since I did the advanced this time, the standard may be all I need. The remaining vibration I feel now is in the foot pegs (could be tires, they're getting close to the end of their life), the handlebars and frame seem pretty smooth all the way up through 4k on the tach.

 
That is comforting news as I intend to use my newly acquired Motion Pro gauge this weekend and have high hopes as to the outcome. Thanks for posting your results.

 
One thing to check that I found last year was my right front fork seal started slowly leaking. I asked our local dealer to change the fork oil and didn't explicitly state to replace the fork seals. I guess I thought that should have gone hand in hand, but my fault for not explicitly stating that.

My throttle body synch was always right on, but after redoing the fork oil and seals that vibration was much less. It was something I wasn't totally aware of was happening, but over time there was definitely more vibration.

Along with the well considered advice of the tb synch you might just check and see if there is a potential of one of the fork seals leaking since you got it back from your shop.

 
Had previously fitted the Grip Buddies, made a big difference to comfort as I already said. Recommended.

Just did the TBS using Motion Pro tool. Worked well and original settings were not hugely out but I used the 'unofficial method' tbs and got them pretty much spot on when increasing revs slowly up to about 4000. Then backed out bypass screws 1/2 to 3/4 turn ( the original setting ) and finally balanced at 1000 rpm.

Unwound the return spring and adjusted a ton of slack out of throttle cable. Both made a very noticeable improvement in rideability.

Only feeling nothing but improvements after a short commute ride so need to evaluate further but all in all, an interesting morning's excercise, worthwhile and made so much more straightforward by the great posts, hints and advice from you guys.

Thanks so much and I will report in more detail in due course.

My TBS tool for loan if you're in the area.

 
Had previously fitted the Grip Buddies, made a big difference to comfort as I already said. Recommended.

Just did the TBS using Motion Pro tool. Worked well and original settings were not hugely out but I used the 'unofficial method' tbs and got them pretty much spot on when increasing revs slowly up to about 4000. Then backed out bypass screws 1/2 to 3/4 turn ( the original setting ) and finally balanced at 1000 rpm.

Unwound the return spring and adjusted a ton of slack out of throttle cable. Both made a very noticeable improvement in rideability.

Only feeling nothing but improvements after a short commute ride so need to evaluate further but all in all, an interesting morning's excercise, worthwhile and made so much more straightforward by the great posts, hints and advice from you guys.

Thanks so much and I will report in more detail in due course.

My TBS tool for loan if you're in the area.
Should've added haven't put the cramp buster on,want to try without.And btw,fork seals appear to be leak free.

 
Last edited by a moderator:
Sorry for my delayed post but I can report the following results in descending order of desired effect,for me at any rate :-

Grip Buddies

Return spring unwind

Taken excess slack from cable

Throttle body sync 'advanced version'

These changes were hopefully going to reduce and/or reduce the effect of vibration at the grips and also improve low rpm rideability.

I expected more from the tbs assuming I did it right, I'm pretty sure I did. Bike does seem to run a little smoother but the grips and spring unwind had the most noticeable effect on 'rideability' for me along with the cable slack reduction.

Clean pickup from idle and at low speed is still not good, something I was advised would be the case but curiously there are times when even this seems to right itself for no obvious reason.

So it would seem the next steps, should I deem them necessary would be the PC V and throttle cable ramp mods.

 
Top