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Starter free spin

motogtp

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Every once in a while the starter will disengage and spin freely. I immediately take my thumb off the button, the starter will spin down, and then with a light thunk, will re-engage. What is causing this? Is it a sign of some terminal issue or fixable? Thanks.
 
Could be the starter clutch rollers worn or the springs getting weak, The rebuild kits are like $35 But on the other hand I have the same problem not very often from the oil I use Amsoil as Dirtdigger brought up before on a previous tread .
 
yes it is the rollers and springs. This normally fixes it but sometimes it won't especially if the other parts the rollers run on are worn. And yes I still cant run Amsoil with this clutch...it just wont grab with it in there. I am sure other synthetic type oils would be about the same.
 
Interesting, the problem did seem to start when I switched to synthetic oil. So far this has just been an irritant so it sounds like I have another winter project. Thanks guys.
 
If you switch back to conventional oil after a couple of starts it will more than likely start working full time again.
 
I like the piece of mind when running synthetic. If it gets worse I may have to rethink but for now it only seems to spin about every third time I try to start it when cold. Once warmed up I don't have the issue, but then again, it only takes a touch of the starter when warmed up.
 
Synthetic oil generally doesn't play well with motorcycle wet clutches, it's just too slippery. There may be synthetic oil out there formulated for wet clutches, I just don't know of any.
 
Amsoil motorcycle oil is compatible with wet clutches. I use it in every bike I have except the 750 because of the starter clutch. Never had a problem with clutch slip with amsoil in any of my bikes, my CBR's or my CRF's. They actually shift a little smoother.
 
Hey guys, sorry for reviving this thread but I was wondering if this was the same issue the OP was having:


That's whats happening to me right now. Not my video but same exact symptoms.

I have another thread posted where it was suggested that it might be the bolts on the starter and I've read elsewhere including this thread that it might need a rebuild. However it just seems a bit to sudden for this no? I owned the nike for a week and the previous owner said he never had that issue. One thing that has changed between his and my ownership though is that he typically had the bike on a trickle charger. I don't know if that might have an effect.

He also mentioned he topped off the oil for me prior to dropping it off. I wonder if he may have used a synthetic oil which is now causing this clutch slipping. I'm waiting to hear back from him. This theory sounds pretty plausible because I don't have the issue if the bike has been sitting for a a couple hours. It only happens if I turn the engine off and try to start her up again. My thought process is that if the engine was just running, the oil is all spread out and coating all the surfaces whereas if it was sitting for a bit, the surfaces will have less oil.

I'm getting ready to consider possibly opening up to take a look at the starter clutch. Perhaps just do the rebuild while I'm at it. I couldn't find any tutorials. Does anybody have any links they could share with me?

Thanks in advanced,

k.i.s.
 
the dohc motor has a similar setup as the sohc. when they slip either the inner hub is getting worn or a couple of the springs inside the clutch could be broken not pushing on the rollers enough.
 
Yes, the DOHC is well known for beating up the roller drive in those clutches. And they don't take well to the modern oils with the 'friction modifiers' that replace the zinc which is pretty much gone out of oil now. So a LOT of better quality oils can make the starter clutches slip. Using bike specific oil can help if it is one that is JASO rated, it will still have zinc but be prepared to pay big for it as now those oils are for 'specialty use' now and the cost has gone WAY up. The zinc dithiophosphate additive is now out of favor due to the phosphate component, the EPA ruled that oil companies nix it.

It's not that the oil is synthetic by and of itself, it's the other additives used now along with being synthetic.
 
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