'96 1100 GS Grinding at Idle

[lee2ray]

So I'm riding my bike back from the dealer after a Hall sensor replacement and I hear this grinding noise--like what you would hear if someone was crunching the gears while shifting a manual trans car. I pull in the clutch but the noise doesn't go away.

I pull off the road and stop the motor. It restarts fine but after a few moments, the grinding returns. I shut off the motor, shift to neutral and restart the bike. No noise. I pull in the clutch. Noise returns.

I ended-up having the bike towed to my house. Two tows in one week. One to the dealership for the Hall sensor and one to my house for ???

Looking for any good ideas for what's wrong with my bike. I hope to fix it myself.

 

[lowndes]

Call the DEALER

So I'm riding my bike back from the dealer after a Hall sensor replacement and I hear this grinding noise--like what you would hear if someone was crunching the gears while shifting a manual trans car. I pull in the clutch but the noise doesn't go away.

I pull off the road and stop the motor. It restarts fine but after a few moments, the grinding returns. I shut off the motor, shift to neutral and restart the bike. No noise. I pull in the clutch. Noise returns.

I ended-up having the bike towed to my house. Two tows in one week. One to the dealership for the Hall sensor and one to my house for ???

Looking for any good ideas for what's wrong with my bike. I hope to fix it myself.

I'd call the dealer FIRST, discuss the issue with him in a very polite, calm, non threatening manner, even if you are displeased with them for reason. It very well could be related to the HES fix. No need in fixing it yourself if they were responsible. Could be something very simple and innocent, an overlooked screw not tightened type thing.

You might try the screwdriver stethoscope on the noise to isolate where the noise is coming from in the engine, trans, clutch. This works really well if you aren't familiar with the trick.

Not sure if your engine needs the OEM cam chain tensioner on the left cylinder replaced with the improved unit. Easy to find out just by looking if your engine needs it and you aren't sure if it has been done. IF it does need doing, it is an easy $80 DIY job, several youtubes about it. I understand that the noise the OEM tensioner makes after 25K or so miles is similar, but mostly at idle/low RPM's. I replaced mine before the noise started.

Please let us know what you find.


Lowndes

 

[m_stock10506]

To replace the HES, they had to remove and replace the alternator belt. Tension could be too tight or loose, or the bolts might not have been torqued to spec. Too late now, but on my way home from a dealer repair I would have either driven or towed right back to the dealer.

 

[lee2ray]

Thanks for the suggestions. I plan to call the dealer. The head mechanic there has been very helpful in answering my questions. If we can work something out, I can probably use my friend's trailer to haul it back there.

 

[lee2ray]

I'd call the dealer FIRST, discuss the issue with him in a very polite, calm, non threatening manner, even if you are displeased with them for reason. It very well could be related to the HES fix. No need in fixing it yourself if they were responsible. Could be something very simple and innocent, an overlooked screw not tightened type thing.

You might try the screwdriver stethoscope on the noise to isolate where the noise is coming from in the engine, trans, clutch. This works really well if you aren't familiar with the trick.

Not sure if your engine needs the OEM cam chain tensioner on the left cylinder replaced with the improved unit. Easy to find out just by looking if your engine needs it and you aren't sure if it has been done. IF it does need doing, it is an easy $80 DIY job, several youtubes about it. I understand that the noise the OEM tensioner makes after 25K or so miles is similar, but mostly at idle/low RPM's. I replaced mine before the noise started.

Please let us know what you find.


Lowndes

Spoke with the dealer mechanic. After some discussion, it seemed that here's nothing they touched that would cause this issue.

While on the center stand and not running, I put the bike in first gear and was still able to turn the rear wheel. While turning the wheel, I could hear and feel gears contacting but not quite mating up.

I pulled in the clutch while turning the rear wheel and I could still hear the same sound but fainter--like gears gears barely touching.

Tried the steel rod. The sound definitely seems like it's coming from the area where the Trans meets the engine.

Any other thoughts about what's going on?

 

[m_stock10506]

......
While on the center stand and not running, I put the bike in first gear and was still able to turn the rear wheel. While turning the wheel, I could hear and feel gears contacting but not quite mating up.

I pulled in the clutch while turning the rear wheel and I could still hear the same sound but fainter--like gears gears barely touching.

......

Unfortunately, what you've now described sounds like a clutch/transmission spline failure. This will require you to "split the bike" and pull the transmission. It is possible that just the clutch splines have failed. "Possible". It is also possible/probable that the transmission splines have failed too. If the trans spline failed you'll either have to rebuild the transmission or buy a used transmission. I have had both of these happen. Your bike can be fixed and you can do much of the work yourself.

 

[cycleman2]

Sounds clutch/spline related. Adjust the clutch and then check that the gearshift is travelling fully to engage the gear and then that it returns back to its neutral position. You could very well be experience a false neutral. Don't baby these transmissions when you are shifting. Preload slightly, pull in the clutch and then a good solid uplift on the gearshift. If you get lazy on the shifting you will have issues.

I also couldn't see how changing the HES would give you your problems. If you take the starter off, you can manually turn the clutch back & forth to see how much play you have. That will tell you if the tranny splines are shot.

 

[lee2ray]

Well here's the problem!

I'm going to give it a go. The repair bill is more than the bike is worth--according to one mechanic.

 

[lee2ray]

I've read a lot about the transmission alignment causing spline wear. Since this is the second clutch in 24k miles, I suspect something may be going on besides normal wear and tear. The Trans was shifting ok but seemed to be a little sticky when downshifting.

Any thoughts about repair vs. replace? Looks like The cost for a Trans rebuild is $1200 + plus the cost of a new clutch $600.

If I do the work myself, there are specialty tools to purchase from BMW or borrow��

The engine runs great and the bike is in overall good condition for its age. Just wondering if I should part it out or fix it.