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Kick start and clutch operation

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CB-500:
Hi everyone

I have a 1971 CB500K0(USA) of which I have totally rebuilt including the engine - The bike itself is currently back to a mid state of rebuild - The engine is fully rebuilt and fitted in the frame however not in a runnable state as no electrics are installed - No clutch lever or cable fitted

The issue I'm faced with is the kick start and clutch actuations - So I thought it was time to reach out to you knowledgeable and experienced folk.

I'll start with the kick start problem - I'm unable to turn the engine over using the kick start - the kick start lever is solid but only once the clutch is fully installed- On one occasion I managed to turn the engine over via the kick start but I had to really jump on it - Remove the clutch pressure plate and all clutch plates the kick start can then be operated.
Breaking the kick start operation down everything appears to be working as it should - Operate the kick start lever the pinion gear engages turns the countershaft gear which then turns the main shaft and in turn the clutch centre hub spins - Release the kick start lever which returns to rest under spring force.
Turn the engine via the crankshaft which turns the primary shaft drive gear which in turn spins the clutch outer housing.
Reinstall the clutch plates and pressure plate - the kick start lever is again solid
With the clutch fully installed the engine still turns and the complete clutch assembly spins via the primary shaft drive gear.
Also when the clutch is fully installed the clutch actuating rod is solid - I'm unable to get the pressure plate to even slightly move.
The clutch has been assembled as per the parts fiche and the parts are within their wear limits - however all parts are originals including old friction discs and plates - The engine is after number 1021198 so part items 4 & 8 are not installed

Friction discs each measure from 3.26mm-3.3mm
Plates each measure from 1.14mm-1.2mm and don't appear to be warped
Clutch springs each measure 32.2mm

The engine has no oil in it apart from what was used for assembly but the clutch was assembled wet using new engine oil - However the clutch assembly was stored in plastic bag for quite some time whilst the engine was being stripped and rebuilt

I'm thinking it is probably a good idea to replace the clutch plates which could be the answer for the clutch actuation problem but surely even if the clutch was locked up you should still be able to turn the engine over via the kick start.

Any help greatly appreciated

Oddjob:
I would look at the gearbox, the symptoms look to be a misalignment between the 2 shafts. Fitting the clutch means these 2 shafts now have to move together and that appears to be a problem.

Are you able to engage all gears?

CB-500:
Yes all gears can be engaged  - however engaging gears is best when the shafts are spun

Is that normally the case?

McCabe-Thiele (Ted):
I'm not at your stage yet if the kick start turns the shaft with no clutch fitted & the gears shift that sounds good. If you fit the clutch basket without the rod etc assuming you are in neutral does it work then?

Oddjob:

--- Quote from: CB-500 on July 16, 2023, 03:15:37 PM ---Yes all gears can be engaged  - however engaging gears is best when the shafts are spun

Is that normally the case?

--- End quote ---

Yes that's normal

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