http://tampa.craigslist.org/pnl/mcy/2830257826.html

What is a front spline?

Item 15
http://www.ronayers.com/Fiche/TypeID/26/Type/TRANSMISSION_/MakeID/2/Make/Suzuki/YearID/48/Year/2007/ModelID/7551/Model/GS500F/GroupID/357836/Group/TRANSMISSION_

Is it possible to only break an output shaft without damaging any of the other gearing? Is the entire transmission damaged or at least suspect?

That's what I was thinking.  I know I have seen others here with high miles and old bikes with worn out splines.  That makes sense.  But an '07?     Afraid there is some serious damage elsewhere.

It would depend on a lot of things. An over-tightened chain and a defect (from the factory) in the spline could have caused it. If it's just snapped off that would be my guess.

I suppose it's POSSIBLE it was caused by some shoddy do-it-yourself work and maybe the splines are all worn down from it?

I would see if they're willing to disclose how it happened and then go from there. Maybe an e-mail? I'm going to go with next to impossible for it to be damaged in a wreck, so you can probably rule that out. I'd be willing to bet that even if the chain was waaaayyyy way too tight that the chain would break before that shaft gave out.

Quote from: Kijona on February 06, 2012, 10:57:21 PM
It would depend on a lot of things. An over-tightened chain and a defect (from the factory) in the spline could have caused it. If it's just snapped off that would be my guess.

I suppose it's POSSIBLE it was caused by some shoddy do-it-yourself work and maybe the splines are all worn down from it?

I would see if they're willing to disclose how it happened and then go from there. Maybe an e-mail? I'm going to go with next to impossible for it to be damaged in a wreck, so you can probably rule that out. I'd be willing to bet that even if the chain was waaaayyyy way too tight that the chain would break before that shaft gave out.

+1

In florida if a chain isn't cared for, it rusts overnight. Rust extends down the sprocket, onto the shaft. Any/all clearances between splines means more rust. 2007 would be about right for a chain/sprocket change this year, and if the front cog was a loose fit on the splines, it would kill them quickly.

In the drz community, we have to loctite out front cogs to the splines (NOT THE NUT!!!) In order to prevent spline damage from poor fit and/or vi bration of the thumpers. Its a very good idea for all splined motorcycle cogs in my opinion. A little time with a torche and bearing puller every 15-20000 miles is not a problem for me.

To repai that gs, I would slap a new chain and cogs, and lotite the front cog if it wasn't damaged too badly. If the damage was severe, id buy a 2nd hand engine on ebay with low miles to familiarize myself and swap the shaft.

2 cents

If it is only the spline damaged, I'd snatch that up and use the difference to pickup a new engine. Pull the damaged one and learn some mechanicals, fix and sell it. I have a used engine and the splines are loose, I'm gradually breaking down my original engine to work out a repair scenario.

If it's just the actual splines, chances are the cog came loose and was moving around while he was riding and it chewed them up. That's way more common on bicycle cranks, but in both cases if they're actually munched up there's nothing to do but replace it and in this case that means a complete engine rebuild. He tried to make it sound like it was nothing major, but it's hard to 'repair' hardened steel, and I feel like he most likely meant replace. He didn't say how many miles the bike has, $1100 could be a good deal if you want to do the work. Even as someone who doesn't mind getting their hands dirty, that one doesn't really seem worth it.