Camchain and tensioner seen up close in a cutaway bike engine

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Fazer FZS 600 OEM Front Sprocket Price - YIKES!

Blog Date - 16 April 2012

There’s this thing with the Fazers, well documented on the unofficial Fazer owner’s club website, that the nut that holds the front sprocket onto the output shaft can come loose.  I’ve already mentioned this before here  I’ve checked my sprocket again this morning and mine seems to be healthy and in place, but I’ll keep on checking from time to time.  The chain’s now done 31,000 miles.  Looking at both the front and rear sprockets and the distance in the dropouts of the rear wheel, the chain still looks serviceable.  But…but…but…it must be due for replacement sooner or later.  As such I thought I’d start the ball rolling to price up a new chain and sprocket kit.

There has been some mention that the loose sprocket nut thing might, just possibly, be due to fitting aftermarket sprockets.  I find it hard to believe but I don’t want to risk being wrong.  Out of curiosity I asked for the price of a front cog at my local Yamaha stealers.  £86.00

Yeah, that’s what I said too.  £86.00!  At that price I could afford to buy 10 pattern parts.  I’m still unsure if this was an error.  I’m still stunned that Yamaha may possible be charging this much.  I plan over the next week or so to go to another Yamaha dealer and see if they come up with the same price.  Online I think I can find some American place that will sell them for $36.00, which would be about £25. 

Even if a genuine Yamaha part is £25.00 you begin to wonder why Yamaha charge this much.  I guess some people are prepared to pay 3 times the price of pattern parts for OEM parts.  Either that or the dealers fit the OEM parts for them and they just “pay the bill”.

I’ll get some more prices from other dealers and get back on this…anyone else priced up a new genuine Yamaha FZS 600 Fazer front sprocket recently?

Extra...

Well I went to another Yamaha dealer...same price...£86... I figure that Yamaha really don't want to sell you these...

Reader's Comments

Derek Dodson said :-
Hi, Try ebay. I recently bought a great quality Chain, front and rear sproket replacement kit for about what you have been quoted for just the front sprocket.

Worth a look?

Regards
Derek
01/01/2000 00:00:00 UTC
Ren - The Ed said :-
There's PLENTY of places where you can get a chain and sprocket kit for less thn just the front sprocket!

I reckon I'll spend a few quid on a decent branded chain, if I can get over 30,000 miles like this one's given me then I'll be happy to spend the extra.

Cheers, Ren.
01/01/2000 00:00:00 UTC
Phil said :-
The issue with the failing isn't down to the sprocket, it was down to the manufacturing of the gearbox output shaft thread diameter being undersize. Generally for metric threads with a 1mm pitch the overall diameter of a bolt thread should be around 0.05mm-0.12mm, so the M6x1 bolt which is a standard size will measure 5.88mm-5.95mm OD. The gearbox output shaft thread was an M18x1 thread so should measure 17.88mm-17.95mm. But some were much less than that, hence the nut kept coming undone or the threads stripped. A 1.0mm thread pitch has a depth of 0.61mm, so imagine the OD being 0.3mm undersize, thats about 25% less thread engagement. No wonder they were failing.
Anyway it isn't the sprocket to blame so you can fit a solid aftermarket one with no problems, I believe the genuine front sprocket has a rubber damper on it to reduce vibration which maybe was one of the ways they wanted to tackle the manufacturing defect which were the undersize threads. Their official 'fix' was to fit a nut which was thicker and so had a few more turns of thread and hoping that would fix the issue without them having to strip the motor down under warranty to replace the gearbox output shaft.
01/01/2000 00:00:00 UTC
Phil said :-
If you measure your gearbox output shaft thread od it should be no less than 17.88mm or there about. If its much less like 17.5mm then you will most likely have problems with the thread stripping. You can do things like drill a small 3.5mm hole through the shaft and fit a washer and 'R' clip or split pin to stop the sprocket coming off.
I re-read my last post and figured it might confuse people, so I added this.
01/01/2000 00:00:00 UTC

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