Driveshaft Spline Replacement?

[Wudy]

Hey guys,
Some of you may have seen my thread a few months ago where my cam chain tensioner went. Anyway, I finally got her started the other day (woop!) and have come to change my chain and sprockets.

When changing the front sprocket, I noticed that the spline is quite badly worn which is giving a couple of mm of slack rotational movement. I did briefly consider just sticking it on anyway because I'm fed up of having this bike sat in the garage doing nothing (chain/sprocket change is the last thing to do).

After looking at the parts diagrams for this part (no. 17) as shown below


It looks like it's a gearbox out jobbie? Would that be right? Anyone replaced one before?

And how much movement in the sprocket is too much? I would like none but it's not like these are 1000cc super-sports bikes...

Thanks for any help guys, hopefully I can get some riding in before the end of summer...

[tomacGTi]

Nice to hear you got it fired up!

It'll have a little wobble for sure, it allows for it to self center but as long as the splines are not rounded off badly, I'd run it. You should be able to tell by where the sprocket rides on the output shaft and compare where it doesn't.

I've never replaced one but I would imagine the gearbox would come apart as does hold everything together.

[Wudy]

Cheers mate! Was so good to hear it running! I'd actually forgotten what it sounded like...

I was having a chat with my dad the other day, and we came to the conclusion that if the old sprocket wasn't causing any problems like that then I might as well just put the new one on.
If it does get worse and slip then I'd have to replace the 'shaft anyway so haven't really lost out on anything, if you see what I mean?

So I guess with you agreeing about it being a 'box out job means I'll just put the sprocket on and see how it goes. Won't be riding much this coming year, and I'll replace it with the next chain/sprocket change if it lasts that long.

To give you an idea of how much it's worn, here's a photo of the old sprocket sat on top of the new one:



The new sprocket fits nice and snugly with no play on the tip of the shaft (on the other side of where the c-clip goes) where it's not worn.

If it ever does go before my next chain/sprocket change I'll dig up this thread and update it! :D

[GK75A]

its a full strip-down mate, some cock of a prev owner thought it would b clever to weld it on. not just mig-welded tho, he used a bloody arc-welder

[Wudy]

It's amazing what people think is a good idea!

I got the sprocket put on and the chain and it doesn't move about once the weight of the chain's on there. Took it for a test ride (first ride since Jan!) and all seems good!

Still want to replace it with the next chain/sprocket change but will come to that when the times comes.