Strange clutch problem
js at strappe.com
Wed Jul 1 13:01:41 PDT 2009
Hi, guys -
Last summer on a 3 day ride we had an odd problem first thing in the morning of
the second day.
Ravi's SV 650 had a stuck clutch, just like a British bike. I've never seen this
before in a Japanese bike. After starting it in neutral and pulling in the
clutch, it wouldn't disengage. Just like my BSA. It had just been sitting overnight.
I tried to break it loose by pulling in the clutch in second gear and cranking
the starter, but no good - the starter just pushed the bike across the parking
lot. Finally I started the engine in neutral, pulled in the clutch, gritted my
teeth and jammed the shift lever into first. Just like I have to do to my BSA.
It worked, and the clutch behaved normally thereafter. No problem the next
morning, no problem since then.
I want to emphasize that this wasn't a cable or linkage problem - the clutch
felt normal when I pulled on the lever. But the plates were stuck together even
though the spring pressure was removed.
In a few days the bike's coming out to my place for a clutch inspection, but I'm
not inclined to replace the friction plates in a working clutch on a low-mileage
bike. Unless, of course, we find something wrong.
Anyone else had this problem on an SV? Or any other modern bike?
Here's my response to Ravi:
> Ravi wrote:
>> what exactly do you want me to buy?
>> Also, where should I buy it from that you recommend?
> That's a tough question.
> Am I correct that your clutch had never stuck before, and that it hasn't
> A sticking clutch that has to be broken loose with a shock is common on
> Brit bikes, and it's caused by a poor choice of friction material in the
> clutch plates or a poor choice of oil. Or both. But with a Brit bike the
> problem would typically occur after the bike had been sitting for a
> while, several days or more. Not overnight, as in your case. And it
> wouldn't go away after one episode.
> Furthermore, I've never heard of this problem with any Japanese bike,
> old or new.
> Since the clutch operates in oil, sticking can be caused by either the
> friction plates or the oil - do you recall what brand/weight oil you
> were running last summer? In the absence of any other data, I'm inclined
> to think the problem was oil related.
> Beth mentioned notched splines in the clutch basket, a problem she has
> on her SV, but that wouldn't cause your problem - notches cause the
> clutch to grab suddenly when engaging, but don't cause problems
> My inclination is to inspect the clutch first - in which case all we'll
> need is a new O-ring for the clutch cover. But if you want we could
> replace the friction plates anyway. It won't take any longer, since
> we'll already have them out, but it'd be a stab in the dark at an extra
> $110 or so.
> I recommend Ron Ayers: http://fiche.ronayers.com/ Check out the clutch
> fiche for your bike: http://tinyurl.com/m2d66t
> Note that the drawing is incorrect - it shows a total of 8 friction
> plates (the ones with the tabs on the outer edge), 7 is the correct
> count. There are 6 of 21441-37440 @ 13.28 each and one of 21440-19F00 @
> $31.24. The steel plates between them don't wear - with extreme abuse
> they will warp, causing drag on disengagement (not your problem).
> You will need the large O-ring for the cover, 11484-19F01, $11.18.
> It's *possible* that the dealer would have this in stock. If they stock
> anything at all anymore.
> This would be the appropriate time to change your oil, since we'll need
> to drain it to work on the clutch. Unless you've just done that, in
> which case we can put it back. Or work on the clutch with the bike on
> the sidestand.
More information about the SV650