preventing driveshaft spline wear?

[erik]

Is there anything I can do to prevent the driveshaft spline wearing out where the front sprocket is connected?
I've seen a post ages ago where the driveshaft spline on a gsx250 was badly worn (pic here. old post here) and done a bit of a search on a GS500 forum and found a few people with the same problem.

The Bandit 400 uses the same method of fixing the front sprocket to the shaft - a loose fit on the spline with a circlip to prevent it falling off.
I'm replacing the chain on the Bandit and noticed some play in the front sprocket, it can rotate a bit on the spline and move side to side (I guess the side to side movement is normal). The shaft is only just starting to wear (pic here). The bike has done about 50,000km.

I've read it's important to put a bit of grease on the spline/sprocket when you fit the sprocket, and that this helps slow the wear. But I don't think it would stop it.
Does suzuki usually attach front sprockets like this?
How do other people deal with it?

I'm wondering if I could put some Selleys Knead It (steel version) on the spline to take up the slack and prevent further wear. Only I might not be able to get it off when I have to replace the sprocket, and I'm not sure if it's strong enough (I've emailed selleys for the strength info).

I might just put some grease on it and forget about it, it hasn't worn too much in the last 50,000km, so I guess it could be considered an acceptable rate of wear.

[Motu]

If you were heading a design team on a new engine Erik,and someone came up with this idea for retaining the sprocket - would the next task you asign him be cleaning the toilets? Some motors seem to get away with this method,some destroy the spline....the sprocket needs to be softer than the shaft of course.

And we put our lives in the hands of these idiots.

[erik]

heh

I guess it would depend on the engine, how budget it had to be. It just seems a bit silly as it's a part of the engine that shouldn't have any movement except when the sprocket is changed, so shouldn't ever wear out. The front sprocket on the Zeal has a spline but is held on tight with a nut, I'd guess (although I haven't checked recently) that there will be very little (if any) wear on the spline from that.

1994 and onwards GS500's have aparently got a front sprocket with a wider hub to prevent the spline wearing out (or to slow it down).

I could be practical and say that it'll probably last another 50,000km if I put a bit of grease on it.
But it bugs me that it'll be slowly wearing away at the driveshaft when it doesn't need to be.

[Paul in NZ]

Shaft drive bikes like mine suffer from a bit of erosion of the shaft splines if they are not kept greased. Not sure of the exact theory but when they dry out, surface rust forms and that is then impacted off and the cycle continues.

The cure is every second rear tyre change (about 10,000km) to drop the rear drive box (4 bolts and the left hand rear shock), clean it all up and slather a bit of hi impact grease on it.

Might work for you too but it seems a lot of drama getting in there and pulling the sprocket off? Does the rear hub have some sort of cush drive? If not, is it possible to fit one from a similar bike?

Cheers

[Motu]

The sprocket being held on by a big nut done up to 946.5 ft/lbs is the best choice,although more than 50% I've ever seen are loose.If you are going to use a circlip it needs to be a good fitting fine spline.The rational from the manufactureres is a bit strange too - the XT600 Yamaha has the final drive sprocket retained by the big nut theory,while the SRX600,which uses the same motor has the floppy sprocket and silly clip.Guess which one give problems?

[erik]

Might work for you too but it seems a lot of drama getting in there and pulling the sprocket off? Does the rear hub have some sort of cush drive? If not, is it possible to fit one from a similar bike?

Cheers

Nah, it's easy to get at the front sprocket, just a cover held on with a few allen head bolts.
The rear hub has a cush drive.
I think I'll take that route and just periodically check it and put a bit of grease on it.