How tight to tighted clutch shoes?

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W.Yorks, UK
I'm just fitting some new standard clutch shoes to my MT, first time round I over tightened them so it took a hell of a lot of revs for them to engage then they stuck open :nono:
Good job I had the car againt a wall or it could have been interesting!

Anyway I've stripped it back down and was wondering how tight the 2 bolts should be? I'm guessing just tight enough to squash the spring washer? By the way this is just the standard 2 shoe clutch not any of the adjustable ones.
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Zenoah torque settings -

Carburetor - 35
Insulator - 35
Cylinder - 70
Crankcase - 65
Spark Plug - 110

Spark Plug Gap - 0.6 ~ 0.7mm (25 - 30 thou)
Ignition Coil Gap - 0.3mm

I cant find anything on clutch torq settings sorry !
I personally have always dogged the bolt up tight !
Make sure you haven't stretched the clutch spring it's easy done ! Reason i say that because it's the spring that allows the shoes to throw out into the clutch bell under centrifugal force not the bolts !
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Thanks for those, they'll come in handy.

Trouble is the clutch shoes pivot on the bolts, so if they're too tight then it will restrict them throwing out as they should, and in my case they were so tight that they stayed open, not even the spring could pull them back together.
I think your best option is to strip it right down clean and rebuild and make sure nothing is sticking because that spring is incredible strong! I would say it got less chance of shoes being thrown out if it's that tight ! But something is telling me you got an underlying problem there other than that blot being tight!
yep I got a normal washer on the "back" of the shoes and the spring bevel washer at the "front".
The clutch didnt engage until I revved the nuts off the engine then when it did it wouldnt disengage when i shut the thing off.
All I can think is that if you need to tighten them as tight as possible then my new clutch shoes are thicker slightly causing the problem. Ive stripped it all and cleaned it and there's nothing that I can see that's wrong. I've put it back again and tightened them just until the spring washer closes and then an extra 1/8 of a turn or so, put a screw driver in between the shoes and it opens (with a bit of force due to the spring) and then closes freely. I'll run it tomorrow and see what happens.
as long as you got the regular washer on back side and beval washer on top i use piston stop screwed in plug hole and i tighten these down tight never had one stick open on zenohas shoes make sure arrow for direction is facing out .on your shoulder bolts make sure there not rusted or dirty i take mine apart on my quarterscale every week i race and take dremel and sanding drum and lightly sand down shoes to take the haze off of them and take wire wheel and sand around the shoulder bolts to get crud off and check holes on shoes where shoulder bolts go through these get corroded to ive took a little barrel sanding disk and cleaned up the hole make sure shoulder bolts go through holes good and don't bind up and make sure your spring is good and not broke or came off and you should be good to go i use socket and 3/8 drive ratchet to tighten bolts down tight and never had problem sticking open. hope this helps
I put it all back together and took it for a blast for 20 mins and it worked fine, then took it apart again to check the clutch and it seems to be alright now, might have been something caught between the shoulder bolt/washers and clutch shoes making them tight.

Thanks to everyone for the help and advice.
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