Jump to content

Front Sprocket Retention - Mild Panic


porter_jamie

Recommended Posts

The GS500 LDDer front sprocket is held on by a circlip. The sprocket itself is ok and not worn, but the splines on the output shaft are worn, so the sprocket flaps about like a prick in a bucket, even with the circlip in place.

Do i need to worry about it? Can i do anything about it? I have noticed some gs50 have a plate which pushes over the splines with 2 holes and you bolt the lockign plate to the sprokect with 2off m6 bolts. i have bought a plate off ebay from a later one to see if it will fit and i will drill and tap the sprocket for the bolts, but i'm not sure it will do much.

Anyone have a bike with a similar setup? Should i just ignore it? Do i need a new output shaft?! It has done 50K miles.

i could tig the sprocket on!!!

Link to comment
Share on other sites

The front sprocket on my Rotax 257 (55bhp 250 single) engine has the same set up (also Aprilia RS125s) and although the sprocket seems a bit loose on the splines, I've never had a problem with it. What's the worst that can happen!

Link to comment
Share on other sites

I had a crm250ar a while back, that had done bugger all miles. That had the plate with 2 holes business and it was loose as hell. I purchased a new plate and sprocket, and it was exactly the same afterwards. I just rode it after that, never had any bother.

Link to comment
Share on other sites

i have found a few references to people welding them on, especially on the early ones. if left, all the splines can wear off the shaft and you loose drive. since the shaft is buggered away, a bit of weld isnt going to make it any worse. i might look for a second hand gearbox to fix it properly later.

Link to comment
Share on other sites

The spliney plate thing: Its splines should be offset with those on the sprocket once the 2 bolts are done up. Then there's a groove in the output shaft for the plate to sit in, so that the splines not lining up mean it can't come off. Then the whole thing just floats, with the plate slopping back and forth in the slot that's quite wide, the idea I think is so that any chain misalignment is taken care of with the whole thing flopping about. Clever really, but a bit of a mess too.

Link to comment
Share on other sites

My City Fly is like this. Took me a while to work it out too.

It's a bit unnerving and you think "Hmm...that's wrong that is" but mine hasn't gone west in over 5000 miles of commuter abuse.

Link to comment
Share on other sites

it worried me that a few bikes in the states had so much wear that they lost drive altogether. as i see it, the output shaft is buggered anyway, so Tigging the sprocket on isnt going to make things worse.

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...