Kick start and clutch operation

[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]

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

Is that normally the case?

Yes that's normal

[CB-500]

With the clutch plates and pressure plate fitted without springs and screws the kick start turns the clutch centre hub - the plates are heard to slip as there is no pressure upon them to turn as one unit - once the clutch springs and screws are fitted the kick start is solid.

There is no drive chain fitted to rear wheel so out of interest I have attempted to work the kick start in each gear- kick start solid

Also with the clutch fully fitted and the kick start in a locked state I have manually turned the engine over - if you put pressure on the kick start lever whilst turning the engine the lever moves downward - I’m assuming this is another indication that everything is engaged

[Bryanj]

It comes to me that you do not have the thrust washer and thecollar the basket spins on assembled correctly, check against pictures in parts book and HONDA manual(available in Ashs dropbox).
Also how are yoy trying to move the clutch pushrod, you wont do it by hand

[CB-500]

It comes to me that you do not have the thrust washer and thecollar the basket spins on assembled correctly, check against pictures in parts book and HONDA manual(available in Ashs dropbox).
Also how are yoy trying to move the clutch pushrod, you wont do it by hand

Thanks that clears up the clutch pushrod not moving - been trying to push by hand as have no lever or cable connected

I’ve been using the parts book downloaded from manuals.sohc4.net

I have the clutch assembled as follows - clutch outer housing (part #1) on mainshaft followed by clutch centre hub (part #2) followed by spacer (part#12) followed by circlip (part #16) clutch lifter (part #9) then inserted into the end of the mainshaft and pressure plate fitted on top

[Trigger]

You can not push a the clutch by hand. Just because the plates measure within spec, it does not mean they will work. Old clutch plates go hard over time 

[Bryanj]

The washer under the circlip is a "selective" fit and there should be some in and out movement on the outer basket.
Cant for the life of me remember whether the 500 is primary or secondary kick

[CB-500]

You can not push a the clutch by hand. Just because the plates measure within spec, it does not mean they will work. Old clutch plates go hard over time 

Looks like replacing the plates is something that will have to be done - would you recommend just friction plates or all plates including metal discs?

Would hard friction plates cause the kick start to lock?

[McCabe-Thiele (Ted)]

I'm confused here if the clutch is assembled and the bike is in neutral how does that affect the kick start becoming solid ?

[Trigger]

You can not push a the clutch by hand. Just because the plates measure within spec, it does not mean they will work. Old clutch plates go hard over time 

Looks like replacing the plates is something that will have to be done - would you recommend just friction plates or all plates including metal discs?

Would hard friction plates cause the kick start to lock?

The kick start would lock if not assembled correctly or the circlip has come off the end. Look in the sump for any parts that have come off. Always replace the end circlip on the kick shaft with a new one.

[McCabe-Thiele (Ted)]

Are the spark plugs fitted - might be worth seeing if removing them changes anything?

[CB-500]

You can not push a the clutch by hand. Just because the plates measure within spec, it does not mean they will work. Old clutch plates go hard over time 

Looks like replacing the plates is something that will have to be done - would you recommend just friction plates or all plates including metal discs?

Would hard friction plates cause the kick start to lock?

The kick start would lock if not assembled correctly or the circlip has come off the end. Look in the sump for any parts that have come off. Always replace the end circlip on the kick shaft with a new one.

Agreed it would lock if not assembled correctly - However the kick start mechanism engages turns the gearbox which spins the centre clutch hub without issue and at the other end the engine turns the outer clutch housing
Once the clutch plates and pressure plate are bolted on then the kick start can’t turn the engine over - You can feel the kick start engage it’s as if there is something further down the line which the kick start is struggling to overcome

The kick start worked before the engine was stripped so obviously something has gone a miss somewhere - But struggling to work out what - As far as I’m aware all gone back together correctly at least that’s how it appears until the clutch is fully assembled

Later on with clutch plates and pressure plate removed I’ll try and wrench just the clutch outer housing round to see if I’m able to turn the engine over in the way the kick start would