1983 GS650G Shaft Drive Rear Wheel Alignment / Offset

[JonnyC]

I'm going a bit crazy here. Finally finishing up my build (picked up the bike in a non-running state and tore it down right away - bad idea) and I'm noticing that the rear wheel is offset to the left side of the bike. It's hard to see in the picture, and that's partly because I adjusted the swingarm so it's shifted more to the right side even though the manual states to center it. When mounting the shocks the left one required more spacers at the top than the right side, so that leads me to believe the frame is tweaked.

So I just want to make sure, this isn't how it's supposed to be, correct? Is there anything I can measure or check to see what the heck is out of whack? At this point I'm just going to throw the bike together and ride it and hope it doesn't handle like crap.

[BigD_83]

I'm not sure how that could happen with the shaft drive, but have a look at the wheel spacers to make sure they are in the right places. It looks to me to be off by the width of one washer, which might happen if you had the wheel spacers on the wrong side.

[JonnyC]

The only spacers are on the right side though, two of them along with the caliper bracket. So yeah, it doesn't make any sense to me.

[posplayr]

Your line seem way off to the left, look at the two screw holes on the rear hoop.
If you are really worried doa wheel alignment. String method works well if you do it right. Descriptions abound just need to find a good one.

[JonnyC]

Well the screw holes on the mounting bracket aren't a good judge, because I just eyeballed those. When I lift the rear wheel up into the frame without the shocks on, it's definitely offset to the left. I'll try the wheel adjustment.

[posplayr]

Well the screw holes on the mounting bracket aren't a good judge, because I just eyeballed those. When I lift the rear wheel up into the frame without the shocks on, it's definitely offset to the left. I'll try the wheel adjustment.

Just a quick measure and your line is way to the right as indicated in the picture. If put a sting from the head stock down the middle of the frame (measuring symmetrically where there are no welds, your wheel looks like it would be close to dead center. The red and green arrows are equal length

Wheel_offset.jpg

[tom203]

"because I adjusted the swingarm so it's shifted more to the right side even though the manual states to center it."

Not sure how you did this- make sure the swingarm pivot bolts fit nicely in bearings and centered.

You must have spacer installed wrong (or wrong caliper beacket).here's mine showing spacer placement

[JonnyC]

Not sure how you did this- make sure the swingarm pivot bolts fit nicely in bearings and centered.

You must have spacer installed wrong (or wrong caliper beacket).here's mine showing spacer placement

It's easy to adjust. The pivot bolts fit just fine, it just shifted the swingarm to the right. Unfortunately the spacers on the right have nothing to do with centering the wheel, since it mates right up to the shaft drive on the left (no spacers on that side).

I'll center the swingarm, do a wheel alignment to see how it compares to the front wheel, and then take a pic.

[Steve]

I'll center the swingarm, do a wheel alignment to see how it compares to the front wheel, and then take a pic.

Good luck with that.

The only "adjustment" possible on the wheel is sideways, via spacers.

What these guys are thinking of is to use the adjusters on the ends of the swingarm to angle the wheel a bit, but they forget that a shaft-driven bike does not have those adjusters.

Yes, it's possible that your swingarm is a bit "tweaked", but it might be twisted, rather than bent. If the right side is higher than the left, the top of the wheel will, indeed, be offset to the left, but the wheel location in the swingarm will be centered.

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[JonnyC]

Luckily there's a swingarm in town for only $18, and it comes with a good condition boot (mine is cracked). I might pick it up just in case my measurements show that mine is tweaked.

[Steve]

With your bike on the center stand, compare the height of the axle holes on each side.

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[posplayr]

Steve , shaft drive have no way to alighn the rear wheel?

[Steve]

Nope. The wheel goes all the way to the left, against the final drive, then a spacer to get the caliper in the right place, then another spacer to fill in what the caliper doesn't. There are no screw adjusters on the ends like you have on your chain-driven bikes.

Those adjusters are there to get the proper amount of slack in the chain. With a shaft drive, you want to keep the axle centered in the hub, so that is where the hole is machined, that is where it STAYS.

That is one of the reasons that a shafty is so much easier when it comes to rear wheel removal/replacement.

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[posplayr]

Nope. The wheel goes all the way to the left, against the final drive, then a spacer to get the caliper in the right place, then another spacer to fill in what the caliper doesn't. There are no screw adjusters on the ends like you have on your chain-driven bikes.

Those adjusters are there to get the proper amount of slack in the chain. With a shaft drive, you want to keep the axle centered in the hub, so that is where the hole is machined, that is where it STAYS.

That is one of the reasons that a shafty is so much easier when it comes to rear wheel removal/replacement.

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I guess that will make the alignment check even easier. OP apparently needs to convince himself that the wheel is in the center of the bike. If it is not the front wheel will not align.

[Steve]

That is why I asked him to check for a twist in the swing arm, rather than a bend.

If the arm is twisted counter-clockwise (viewed from the rear of the bike), the top will be to the left, as he has observed, and the bottom will be to the right of the centerline.

Because of the diameter of the tube inside which the shaft runs (which is the left side of the swingarm), it would be hard to bend the arm, but I think the right side could be lifted, giving the arm a twist.

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