Drive train rattle when lugging

MikeinNZ

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Trying to figure out if the noises my S10 makes are normal..
1st noise is a rattle type noise when it’s in second and at idle ( like chugging through a car park etc) it sounds like gear backlash and could well be. When off in gear on the Center stand there is a heap of lost motion in the transmission and while having a read of the manual I see they have a Torque Damper Cam on the middle drive pinion gear... Has anyone seen this Cam and would care to explain how and what the Cam does? I can’t figure out what the lobes react against in the manual and if this is where the slack in the trans comes from?
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2nd noise is a noticeable whine when backing off the throttle in top gear at high speed... sounds kind of cool but wondering if anyone else has this? The rest of the time the trans is quiet, shifts well and goes well.

Thanks in advance
 

EricV

Riding, farkling, riding...
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Did you feel that just now? It was a virtual slap to the back of your head. STOP LUGGING THE ENGINE. Idle in 1st is 7-8 mph, (10-11 kph). There is no reason to move at idle in 2nd gear.

Stop playing with it and ride the bike. Nothing you're doing has anything to do with how it works under load.

Have you ever lubed the cush drive gear when the wheel is off? Have you checked or changed the gear oil in the diff pumpkin? It's shaft drive, there is some more normal drivetrain noise, compared to chain drive bikes.

What model year is the bike, and how many kms or miles are on it? This will help everyone to help you better.
 

WJBertrand

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That cam is designed to allow rotation between the shafts under extreme loads to avoid breaking the shafts. Imagine a mechanical safety valve if you will. Normal riding will not cause the cams to rotate over their lobes. All engines and drivelines will make nasty noises when lugged and you risk damaging the crank main & rod bearings by doing so
 

MikeinNZ

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Thanks for the slap Eric... It was a bad use of the word lugging, should have been idling.
2010, done 66,000ks.
Cush rubbers are good. Final drive oil is clean.
Universal is good.
None of the noises sound bad. I’m just interested to know if it’s normal.
I idle through car parks so not to scare little old ladies.. It has a full Arrow system ;)
Thanks for the explanation on the lobes WJ. I hope I never hear it working.
In first gear (engine off) on the Center stand it has 2.0” of slack (measured at the tyre edge) in the drive train. If you guys say this is normal I’ll sleep easy.
Thanks again.
 

Don in Lodi

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Mine is at least two inches of slack. My Royal Star had more, pretty much the same differential.
 
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