Gearbox locked after rebuild

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Suede Ed
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Main scooter: SIL GP200
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Got a SIL 200 block, to swap in my 150. Rebuilt it, problem is the kickstart is jammed solid. Opened the engine up expecting a shimming problem, however after removing the clutch i refitted the case cover and the kickstart turned the gearbox. Thought it might be the top end jammed, but it turns fine. Put it all back together... and the kickstart wont budge ? Any ideas? Cheers.

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garry inglis
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The round part on the kickstart is jamming on the top plat of the clutch you have to grind some off the kickstart then try it then maybe a bit more till you get about 1mm clearance

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Warkton Tornado No.1
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As Garry said, the problem is most likely the kickstart mechanism catching the clutch. I've had, on occasion, engines that had never previously been taken apart from the day Innocenti assembled them with evidence of this occurring.

You will see in your engine witness marks of the rubbing.

If you linish some off the kickstart mechanism, that should allow it to clear, but don't go mad with it!

When you next assemble the cover onto the crankcase, just nip up gradually about four to six fasteners to pull the cover in & keep feeling via the kickstart lever if the interference has been eliminated.

I can recomend extra thick chaincase gaskets as well. They help with the clearance issue & are usually re-useable if you grease them up prior to fitting. They need to be re-useable @ the cost :!:
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Suede Ed
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Cheers gents, i should have remembered that, i naively thought the sidecase from my smallblock would go on with no issues, as its the same clutch. Took the decision to remake the kickstart mech and noticed the inner bush was a little proud, so ive fixed that and will try again when I'm back in the garage

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Suede Ed
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Having tried to see where the kickstart shaft is hitting the clutch ( covered it in marking blue) and found no marks, I have rebuilt the kickstart mechanism, found bushes protruding and corrected, re-shimmed etc. Still Jammed :? . I have noticed that with the whole clutch removed the kickstart turns the box, but the box seems jammed with the clutch fitted and torqued?
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garry inglis
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There should be a 0.7mm washer behind the clutch basket sits on the cluster

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garry inglis
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No28 Image

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Suede Ed
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Cheers Gary, gonna go for a strip out of whole gb including bearing. I'll try another combination of different layshaft, bearing and endplate, as gearbox is sfiff as f'''', even with a 1.6 shim. Maybe its due to using a new SIL gp 200 gb and an endplate with a new bush?
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HxPaul
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Might be the end of the kickstart shaft(The part where the piston goes in) catching the first gear and preventing it from turning.http://www.scooterrestorations.com/imag ... kstart.asp
Lambretta67
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My s.i.l. gp200 engine did the same thing after about 3000 miles. Turned out the crank roller bearing had fallen apart & jammed everything up. Put in a new crank. Runs lovely now
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