Drive Train Backlash

[Wingnut]

My 82 850G seems to have a lot of backlash in the drivetrain. I have checked everything, especially the forward drive shaft bolts, and all seems well. The backlash that I do have is in the transmission or the transmission final drive unit. Watching the drive shaft, where it goes into the back of the gearbox, shows virtually no lost motion from there to the rear wheel. The noise and lost motion is in the transmission, or in the transmission 90 degree drive. I am wondering if this is a problem. It seems a little clunky on the road when getting on and off the throttle.

I measured the lost motion in the following manor. With the bike on the center stand and the transmission in first gear, I rotated the wheel forward until it stops. With a tape measure placed at the outer edge of the rim, not the tire, I marked a spot and rotated the tire backwards while holding the tape still. I got about 1 1/4 inch of free travel at the outer edge of the rim.

Could someone be so kind as to measure their rear wheel free play in the same manor and advise. Should take less than a minute once you find a tape measure. Maybe it's nothing and this is normal but I am trailering the bike to Fla. for a month soon and want to be sure it's all right. Short of transmission disassembly I can't figure out how else to tell if all is OK.

Thanks in advance,

Bob

[focus frenzy]

1-1/4?? is that all???

must be nice!
I have not measured mine but can say it is way more than that and it hasn't hurt mine yet. I my self have put over 45K miles on it and it hasn't gotten any worse.

don't worry about it.

[Wingnut]

1-1/4?? is that all???

don't worry about it.

Thanks focus,

I do waste a lot of money and time on percieved problems than turn out to be nothing. I know it and recognize it. I just can't seem to stop it though.


I believe that MOST of the time machines do not just stop working. They almost always will talk about their problems before they just quit. Maybe it's a rattle or clunk or ticking or sputter or dim bulb or whatever. But there is almost always a warning sign and I try to be in tune with that and am constantly listening and analyising. Sometimes too much though maybe?

[Anonymous]

Drive Train slop

Just got back on this site in hopes of finding help with my final drive. Seems my '82 1100 G has worn down the splines between the final drive and the rear wheel. I also had noticed slop, but decided it wasn't a big deal. Now I'm looking for probably both a final drive and a new rear wheel at the salvage yard. It is hard to spot, but I can see wear on the spline teeth. Guess I didn't grease often enough.

[Jethro]

1-1/4?? is that all???

must be nice!

I was gonna say, my chain model has at least that, if not more like 2 1/2 inches!

[duaneage]

If you study the transmission carfully you will see that a certain amount of backlash is built in. The output shaft has this designed so that when you shift there will be some tolerance for the driveline to work with. A chain provides play for the transmission to work with, however a shaft would be a direct connection so there is a slight amount of "slop" that is necessary.

The rear drive spline mounts into a rubber insert for much the same reason, provide a cushion against hard sfifts, but of course we never shift hard on our motorcycles, do we? :twisted:

[jimcor]

Nothing had more drive line lash than the 1972 650 Yamaha XS2. Chain drive, too. Only bike I ever bought new. Just something you learned to live with, never a problem and after awhile you forgot about it.

Talk about a bike that was loaded with chrome! Made my 550L look dull.

[tfb]

The GS1000S I used to have (chaindrive, not a shaftie) had so much freeplay, especially in 2nd gear, that it was very hard to ride smoothly in that gear. But the other gears were always a lot tighter, as evidenced by the same method that Wingnut has used, ie. rotational freeplay at the rear wheel.

Anyway, a couple of years ago I was looking at another GS1000S for sale, and as part of the inspection process I popped the old girl onto the centrestand, and checked the freeplay in all the gears at the rear wheel. It turned out to be a nice tight gearbox, when compared to my old GS1000S; hardly any slop at all.

So in the end, I think a lot of this drive-train backlash and freeplay, gets down to how worn the cogs are in the gearbox. Just something we have to live with, probably.

Mike.

[duaneage]

The Clymers manual has a real good picture of the output shaft and the cam mechanism that creates drive line play. It si there for a reason, to absorb shock when you shift , decelerate and the swing arm moves.