Gear Box Problem

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Treeman
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Have carried out a winter strip down, amongst other things to resolve poor gear selection. Have found the gearbox had resistance when stripping it. Took it apart and couldn’t see much wrong. Once reassembled and the end plate is tightened down the resistance is far too strong. Before tightening it, it has little resistance and moves freely. Have tried changing the shim on the gear box, but no luck. Anyone got any ideas what could be the problem?

Thanks in advance

Treeman
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rog60
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Try tightening down the clutch bell (rear sprocket) to pull the gear mainshaft through. Often frees up the gearbox.................
NO IT'S NOT A F***IN* MOPED!!!!!!
bristolmod
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I had a similar problem- it turned out it was the bearing in the end plate which wasn't fully "home".

A quick press in in the vice and problem cured- worth looking at

Chris
Scootering since 1968.
DJB
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Is the end plate the original to the case, as this could cause you problems, i.e not in line.
The best way to check is to put just you layshaft in and put your rear hub on tight. Then put the end plate on to see if they line up. I have had this happen to me.There are all different size end plates.
Last edited by DJB on Wed Dec 23, 2009 1:37 pm, edited 1 time in total.
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byron
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what layshaft are you using ?
I found with the thicker series II type that it needs careful assembly at the endplate end, the end of the shaft here does not have a dish like on later layshafts, so the shim has less room. I have ended up taking about 0.2mm off a shim before the gearbox would turn. mind you that was on an engine with a load of badly fitting, poorly made components...
Treeman
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Joined: Mon Jul 06, 2009 6:15 pm
Main scooter: GP 225 TS1
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FEEDBACK

Had a half mile ride on it yesterday, after a delayed rebuild.

When rebuilding the engine we discovered that the gear cluster bearing wasn’t sat home all the way, so we made it so.

It would seem that the gears are selecting well now and the problem seems to have been dealt with (the slipping 5 plate clutch which seems to be topical, still needs to be tested to see if it still slips or not - advice).
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