Vibration/grinding/rough-feel through right footpeg

[gabriel_gs]

So I've bought myself another LC GSA - a 2018 with all the toys.

I've had one before but only had it a few months and can't quite remember if I had this 'issue'...

Basically there's a sort of 'rough' vibration at times through the right footpeg - I'm 99% sure I can't feel it through the left.... comes and goes and only lasts a few seconds, but now I've noticed it I can't 'un-notice it'

It occurs at various speeds/gears/level-speed/turning.. it's hard to pin down exactly what makes it appear. What I do know is that I can pretty much always make it happen at about 43mpg in 4th gear, 3500 revs or so and at a level speed, so not accelerating.

I seen some other threads mentioning something similar, others describing it as a 'chatter' or even a sort of 'grinding' vibration sensation, all saying that like mine it's felt through the right-hand footpeg, almost like a 'metal on metal' feel... but very faint and it goes.

I've found equal numbers of posts saying "it's normal and don't worry about it" - I've had enough Boxer twins to know they have their quirks, bumps and tics, but I don't remember this particular 'idiosyncrasy'

I bumped into a guy with a similar model GSA at Box Hill and when I quizzed him he started nodding knowingly and said he knew exactly the sensation I was describing - for him he had the cardan shaft-FD splines lubed and that solved it for him. He seemed to think it was a known issue and should be sorted FOC by BMW... Other posts I've found online pointed to shaft-to-FD seizures and others mentioning the cardan shaft 'service update' and that it might be related to that... some saying it'll be fixed for free, others siting massive bills.

But it might not be that at all? (BTW, the cardan shaft 'service update' work was done on mine in 2022 apparently)

Either way it's got me worried.

I'm taking it in into BMW on Friday, but anyone with similar experience that might be able to give me some 'starters for ten' for when I take it in and talk to them?

I bought the bike privately, so no comeback in that regard and no warranty - desperately hoping I don't live to regret it!

 

[theoneandonly]

on a Guzzi , I'd look at the driveshaft .
it is right by your foot .

 

[gabriel_gs]

Yeah I’m worried it’s drive shaft or FD related

As an update I went out today to try and replicate it consistently

Seems that 3rd or 4th gear at a stable pace produces it, as does cornering - gentle weaving along the road makes it appear every time

Any other thoughts welcome, but otherwise I’ll see what Vines say on Friday - at the very least, it’s easy to reproduce the symptoms

 

[Nick dj]

Are you sure its not usual engine vibes transmitted to the frame by the exhaust that is on that side?
I switched to a Cobra titanium carbon and instantly noticed the reduction in the right foot peg.
It weighs nearly 6 LB less and is just held in a carbon cradle, sounds good I couldn't be happier way better than a Acra

 

[gabriel_gs]

So an update.

I’m not certain that the tech detected the same vibes as me, but…

He did immediately report that the RHS cylinder was making more of a rattle than it should. After inspection the intermediate shaft’s needle bearing was failing with the axel that passed through it being very worn/scratched, so both need replacing (£350-ish).

Secondly the rear shock had no damping at all (he demonstrated it pushing down in the bike and we could here it ‘bang’ as the spring returned), that bright the occasional ‘thunk’ I feel while riding, so it needs a rebuild. I’ll send it off to T-tech, as they (and plenty of others online) have advised - £350-ish including shock removal/reinstall.

The front brake pads, one had an odd crack running through it (back face to front), so front pads need replacing.

And then the rear tyre, had some life in it but he mentioned it had worn ‘oddly’ on the sides, as well as being a touch squared off, so that might also be contributing to the vibes, so that’s also being replaced.

Add all that up and include the labour and investigative work (and include the shock rebuild cost) and it’s gonna be around £1400 I think.

Ouch.

In the flip side, he’s adamant that the drive shaft is fine

 

[JohnnyBoxer]

So an update.

I’m not certain that the tech detected the same vibes as me, but…

He did immediately report that the RHS cylinder was making more of a rattle than it should. After inspection the intermediate shaft’s needle bearing was failing with the axel that passed through it being very worn/scratched, so both need replacing (£350-ish).

Secondly the rear shock had no damping at all (he demonstrated it pushing down in the bike and we could here it ‘bang’ as the spring returned), that bright the occasional ‘thunk’ I feel while riding, so it needs a rebuild. I’ll send it off to T-tech, as they (and plenty of others online) have advised - £350-ish including shock removal/reinstall.

The front brake pads, one had an odd crack running through it (back face to front), so front pads need replacing.

And then the rear tyre, had some life in it but he mentioned it had worn ‘oddly’ on the sides, as well as being a touch squared off, so that might also be contributing to the vibes, so that’s also being replaced.

Add all that up and include the labour and investigative work (and include the shock rebuild cost) and it’s gonna be around £1400 I think.

Ouch.

In the flip side, he’s adamant that the drive shaft is fine

Hope it was a cheap bike when you purchased it
Ouch

 

[gabriel_gs]

Yeah it all sucks… but to be honest I did get what was otherwise a very well looked after and spec'd bike (full yearly BMW service, not a mark on it, all the toys) at a very good price… I could easily have spent an extra £1000-£1500 on a similar spec, so it’s all relative in the end

Previous owner is being pretty good about it too - already indicated he'll contribute towards the costs, which frankly he could have just ignored - 'sold as seen' and all. He's been very apologetic and is rightly a bit upset that his local BMW garage for not picking these things up (they would have eventually had to have been done anyway), but picked up they have been. Just sucks that it was on my end, not his, but hey yo, there's worse things in life to worry about

 

[Deleted account 250722001]

Top marks for your previous owner.
If only mine had had such integrity...

 

[gabriel_gs]

So the bulk of the work is done - new front brake pads, new rear tyre, new intermediate shaft and axel, all investigative time and labour... came to about £850

The vibration is WAY better, though I can still detect it a bit... but that might be normal vibes I'm feeling now.

The rear shock I'll remove/refit myself to save a few quid, so when T-Tech are back in a couple of weeks, it should be about £250 to refurb.

I'll report back once it's all done.

 

[gabriel_gs]

All sorted!!!

Shock came back and the bike has transformed. Ride is super smooth and the vibes are no more - kudos to T-Tech

Back in love with the bike