Just got the M20 back together. trying to kick it over and it seems to be loosing the link from kickstart to engine.

Has been stood a while emptied oil which had wet sumped. Topped back up the oil tank.
When I kick it over it seems to loose the link between the engine. Could something be slipping, clutch maybe?

Cant understand it. Going inside to catch my breath not fit as I used to be. Can only kick the thing about 20-30 times before I wear out.

Off for a cup of tea and a breather, while checking out the M20 Forum.

It does try to fire one or two times so cant be far off but it seems like the kick start just turns without turning the engine now and again.

Any hints?

Paul C

Paul I think you will have to check inside the primary case, starting with the crankshaft cush drive nut....then the clutch. Ron

email (option): ronpier@talk21.com

I was hoping not.
But have a slight oil leak from that side between the engine and the case so, it needs to come off.

Happy I got a couple if pops from the engine so gives me confidence the new Barrel and piston is doing its job.

Paul C

Hi Paul,

Mine did this a few years back, the bike had been running great with no problems at all. I laid it up over the winter for around 6 months. I checked it after 3 months a notice it had started to empty the oil tank, i left it thinking i would drain before i started it in the summer. Come Summer i drain it as it had near emptied the oil tank i also drained the chaincase as it fills the sump to main bearing level then runs into the clutch chain case. Started it ok it did have a little clutch slip on starting but as soon as i tried to ride it the clutch slipped really bad infact you could not ride it.
I pulled it down and took the single spring clutch cover off. The clutch was full of oil, gasket OK so it has come in from the back of the clutch where the rollers are. I had to soak the plates in petrol for a few days then all was OK. I have now fitted one of the stainless sumping valves that are made for the B C and M range, they screw direct into the engine in place of the feed union, you dont even need to shortern the oil pipe. Bike running fine now and sumping valve works a treat, around £37 but says you a lot of bother.

Tim W

email (option): t.j.walker@btinternet.com

Thanks.
Sounds favourite to me.
Will see when I take that side apart.

Thanks for ideas.

Nice oily plates. Just removed them.



It seems I have a 4 bolt clutch.



Do the sprocket teeth look worn to you.

That's a 4 spring Triumph clutch which runs wet...So oil contamination isn't your problem....Ian

email (option): ian@wright52.plus.com

So ok there then, presume sprocket teeth ok.
nice to see all ok inside.
Ho w much tension do you place on the four spring screws when you put them back on, seem to be no locking washers or retaining method to stop them unscrewing.

need couple of cork gaskets for footrest spacer and reapply silicone. It seems someone else did that previously.
Will try see if adjustment makes any difference when back together.

Paul C

Memory could be serving me wrong here, but I seem to think that the springs should be compressed with a narrow screwdriver or similar whilst the retaining 'screws' are fastened. There are two pips on the face of the screws that go against the spring tops. One or the other of these will be in contact with the end of the spring once the tension is released. This stops it from coming loose. For this reason the springs have to be compressed or the sharp spring end will wear away the pips as you tension the screw and spoil their purpose. Again if my memory is correct, the screws have to be fastened until the end of the stud comes level with the end of the hole in the fastener. Triumph used to have a special screwdriver with the centre missing to allow for doing this job, the gap allowing for missing the stud.

An old chisel with a groove cut out in the middle is my choice of tool for Triumph an A10 clutches.

Regards

Pat

email (option): sacombsashtrees@hotmail.com

There are also two spring 'weights' for the Triumph clutch...Shorter, heavier rated springs are for the larger Triumph twins...The longer, lighter rated springs are the best for single cylinder applications giving a nice light operation after adjustment...

I run these lighter springs in all the Triumph clutches I fit to BSA singles, including tuned and oversize B33s...They can handle the power quite happily in those applications...Ian

email (option): ian@wright52.plus.com

I am giving them a light clean.
Mainly to see how the thick and worn the material pads are.
Then to measure how worn they are.
Is it worth change one if it is below tolerance or replace a set?
They look cheap enough, at Dragonfly.
the plain plates look pretty good so no need to change those.

Ian, the ones on this clutch are the lighter ones, just need to make sure they are still roughly the correct length, will check for wear/ fatigue.

The specs on the technical section are obviously the originally fitted clutch bits.

Paul C

Just got my delivery from Dragonfly, a couple of plain steel plates and a new clutch driving plate. One was pretty low in the pads so replacing it. Also one steel plate was pitted, not at its best so replacing that too.
Do you give the drive plate a coating of oil before fitting or let it pick up oil when it is in the clutch drum?
No details or info on triumph clutch. So flying blind.
Noted the comments and have made a little driver with center missing to tighten up the screws.
Hopefully will work ok.

Then will test out the adjustment.

Now confused
Has anyone the drawings and part list for this clutch.
Is this info correct on Dragonfly website.

https://www.draganfly.co.uk/index.php/bsa/bsa/a710--b3133--c101112--m202133/category/910-4-spring-triumph-type-without-cush-drive

I ordered from the website, only because the plate looked right on the picture ( 10 lugs ) but looking back on the main drawing it seems to be 8 lugs on the clutch drum and plate? Although the steel plain plates are ok?

So what model and clutch do I have on my bike?







The screw do not look right seem to be hand made. Will it matter? Has been working before so should be ok.

Not sure of the detail

This seems to be the one on my bike

https://www.draganfly.co.uk/index.php/bsa/bsa/a710--b3133--c101112--m202133/category/909-4-spring-triumph-type-with-cush-drive

Aloha,

From memory I think there is supposed to be (as someone stated above) two little "pips" in the face of the nuts that engages with the spring and keeps it from unscrewing. Not certain how necessary they are, but maybe...

This is how a Triumph clutch is adjusted, as taken from on my 3-spring clutch on my -69 Bonneville but same concept (i hope and assume):

- Tighten the four nuts that compresses the springs until the screws are approximately leveled with the top of the nuts. Or maybe a little more, to where they stick out a tiny bit (depends on the health of your springs also).
- Slacken the cable more than usual, or disengage entirely.
- Adjust the screw in the center of the domed plate on the clutch so that there is a little play in the rod. This i best checked on the other side of the clutch, where the lever pushes the rod. No slack and the clutch will slip (and wear will take place), to much and the clutch won't work properly. PLEASE NOTE that this particular step might be different on your BSA gear box!!! Probably is now that I think of it. Ian, or someone, please fill in the missing info here.

Now!
Tighten the clutch cable (of course leaving a little slack as you always do on a clutch cable).
- Stand on top of the bike looking down on the clutch.
- Pull the clutch handle in.
- Kick the bike over slowly.
- You will now most likely se that the domed outer side of the clutch does shifts around a bit. Adjust the nuts by "half turns" until it is leveled "around the clock", this part i slightly easier on a three spring than on a four spring.

When you have the bike running you may find three things:
1. The clutch is working perfectly.
- Congratulations!
2. The clutch works good but is a bit hard to pull.
- Release the screws some and repeat adjustments as above.
3. The clutch slips.
- Tighten the screws and repeat adjustments as above.

Hope I got everything right!
Ian and others are more than welcome to chime in and correct me where i may have missed something.
I have done this successfully on my Bonneville but have a single spring clutch and an early B33 gear box on my M21 so don't know the exact details there.

Good luck!

/simon