Honda-SOHC

SOHC.co.uk Forums => CB500/550 => Topic started by: andy120t on June 26, 2021, 02:12:03 PM

Title: Clutch won't disengage.
Post by: andy120t on June 26, 2021, 02:12:03 PM
Cb550f2 - the clutch isnt disengaging. I've taken it apart to check the plates aren't stuck together. Just wondering now as a first step to understanding and fixing it, what exactly should move in there?....

When I pull in the clutch handlebar lever, it raises the lever by the kick start and the cam in the cases pushes the actuating arm which pushes the 'pushrod- with- two-ball bearings' thing. Then what? What moves after that and in which direction?

Also, I think someone may have been in there before me:
If I'm missing the washer behind the circlip on the clutch basket, is that a major problem?!

If I push the ball bearing rod thing, should I be able to see the plates separate? (at the moment I can't get any movement)

Should the actuating inside the case arm have a spring on top of it? Currently mine doesn't and the arm just flops forward when I try to install the case. I saw a thread elsewhere that says the spring which is behind the arm on mine, should be in front of the arm (see piccie).

[attach=1]

If I tighten the 4 bolts and plate too much would that stop it working?

Thanks for any thoughts!
Title: Re: Clutch won't disengage.
Post by: andy120t on June 26, 2021, 03:17:51 PM
Found the service manual figure 356.. looks like my spring should be in front of the arm, not behind so I need to fix that.

Any thoughts about the other questions though?!
Title: Re: Clutch won't disengage.
Post by: murdock on June 26, 2021, 04:59:35 PM
the spring arm goes over the lever
Title: Re: Clutch won't disengage.
Post by: Bryanj on June 26, 2021, 05:01:30 PM
Yes Ken like a super short pushrod
Title: Re: Clutch won't disengage.
Post by: murdock on June 26, 2021, 05:05:16 PM
Uppp
Title: Re: Clutch won't disengage.
Post by: murdock on June 26, 2021, 05:07:20 PM
https://www.youtube.com/watch?v=Em18nFMpH_s&ab_channel=CZeroMedia
Title: Re: Clutch won't disengage.
Post by: andy120t on June 26, 2021, 05:09:32 PM
That sounds like what I've called  the 'pushrod with two ballbearings' . One ball bearing at either end. I thought that if I pushed this then I would see the clutch plates release, (as that's what the arm works against) but when I press it - very hard- nothing happens.


Title: Re: Clutch won't disengage.
Post by: murdock on June 26, 2021, 05:13:47 PM
Upp
Title: Re: Clutch won't disengage.
Post by: Bryanj on June 26, 2021, 05:41:14 PM
You will never push hard enough by hand to move the clutch, lots of mechanical advantage in the system to increase leverage
Title: Re: Clutch won't disengage.
Post by: philward on June 26, 2021, 08:29:13 PM
You may have already done this Andy, but check the CMSL schematics (link below basedon UK 550F2) for checking you have all the parts in the correct order.

https://www.cmsnl.com/honda-cb550f2-super-sport-550-four-1977-england_model17121/partslist/E08.html#.YNd-U-hKjWU

https://www.cmsnl.com/honda-cb550f2-super-sport-550-four-1977-england_model17121/partslist/E07.html#.YNd-hehKjWU

When you say it won't disengage, do you mean when the engine is running - i.e., it stalls when you put it in gear (because the clutch plates are stuck together). If so, (if you havn't already tried) try using the kick start with the clutch lever pulled in - it may then free up
Title: Re: Clutch won't disengage.
Post by: andy120t on June 27, 2021, 09:56:57 AM
Thanks Phil I've only identified a missing thrust washer. Other posts suggest that could have been installed behind the clutch basket so I'll dismantle again and check.

This video https://m.youtube.com/watch?v=JhTf7cBeGcs (https://m.youtube.com/watch?v=JhTf7cBeGcs)

..makes it very clear exactly what each clutch part connects to, which I wasn't 100% clear about, so might be useful for others. I certainly hadn't understood the detail of how fibre and steel plates linked the different parts of primary drive and gearbox...just always knew that that was what the clutch 'did'!

I still don't understand what the CB550 clutch pushrod ( the rod with ballbearings on ) is pushing. This video is clear, as it pushes from the left so simply pushes the pressure plate outwards ( to the right of the engine). On my engine the rod is pushing in from the right, so how does that inward action push the plates outwards? Or are they disconnecting inwards?

My lever, when correctly attached to the clutch, is almost impossible to move, so if the clutch disengages inwards, then maybe I have something incorrect or stuck behind the basket.

Title: Re: Clutch won't disengage.
Post by: Bryanj on June 27, 2021, 02:12:22 PM
The clutch "inner" that the steel plates are splined to is in two parts, the pressure plate that you cant see has 4 posts that go through 4 holes in the hub with the springs round the posts held by washers and bolts, now the pressure plate has teeth on the inside that have to mesh with the teeth on the hu but THIS DOES NOT HAPPEN in every position of the posts in the holes but only 2 and this could well be what you have done wrong.
Hope you understand that explanation, piece of pee to show you but a swine to describe
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