Any motorbike clutch experts on here?

wasted years · Nov 4, 2018

We've got a beta 125 trials bike , I replaced the clutch side crankshaft oil seal recently as it was using a bit of oil from the clutch.
Bike was on ATF in G/box and no clutch drag at all before being taken to bits even when cold.
Clutch drags all the time now , still ATF, plenty of 'throw' in clutch when cover is off, plates appear loose with lever pulled in, plates appear in very good nick, I have replaced lever master cylinder seals , replaced the oil and bled it.
I have studied the parts explosion and everything is where it should be, the only thing I can think of is that the plates are in , in a different order/position to where they were , would that cause drag til they wear in?
Doesn't slip under throttle at all.

newladd · Nov 4, 2018

the steel plates have a flat side and a slightly beveled side,make sure they all face the same way.

wasted years · Nov 4, 2018

Didn't know that will check.

ARW · Nov 4, 2018

Make sure no plates are stuck together

Mursal · Nov 4, 2018

Were the plates renewed with the oil seal?
If so I think they like to be soaked in oil before fitting.

Click for another with the same problem

timmyboy · Nov 4, 2018

Would that be the same spec atf oil as used before hand?

wasted years · Nov 4, 2018

timmyboy said:
Would that be the same spec atf oil as used before hand?

Yes, quite often trials bikes drag when cold but this one never has and strangely it always had a nattle on the clutch when in neutral with the clutch out, that nattle has disappeared.
Going to check the plates are right way round first, I did have a look but couldn't see a 'sided' way.

simon-0116 · Nov 5, 2018

Clutch basket hasn't got groves / steps worn in it. Sides should be smooth so rise up down evenly. Quick run with a file if so.
Think google is your friend ad beta had a problem on 250.s

Kiwi Pete · Nov 5, 2018

simon-0116 said:
Clutch basket hasn't got groves / steps worn in it. Sides should be smooth so rise up down evenly. Quick run with a file if so.
Think google is your friend ad beta had a problem on 250.s

This was my first thought, clutch baskets nearly always need a file up with new plates (based on lots of frustrating pull-it-apart-agains)
As above it isn't hard to put a plate (or all the plates) in the other way .

Also, @wasted years - is your bike a pushrod actuated clutch, or hydraulically operated, I'm not familiar with your machine but sometimes these symptoms are because the pushrod has been put in the wrong way and they have worn differently, throwing it out of adjustable range. Thinking Yamaha Ag 100 when I type this..

It could be the glue on the new friction plates.
It could be a shim kit is required?
Or it could be pushrod balls, a sticky slave cylinder (if hydraulic) but I think it will likely be the new plates binding in the basket.

wasted years · Nov 5, 2018

It is hydraulic down to the piston (obviously) then the piston pushes 2 rods with a ball bearing in between the 2 rods to 'throw' the clutch.
When we first put it together the ball had rolled out (didn't notice it) onto the floor but a quick 'google' told us someone else in the known universe had done the same and I realised my mistake.
Clutch basket edges look smooth, everything was spot on before I took it to bits so there is a mistake somewhere.
First thing is to check the steel plates are right way round, I also have a number of someone who is supposed to be the man what knows.
I hate being beaten. Grrrrrr.

Kiwi Pete · Nov 5, 2018

You aren't beaten yet.
I think the steel plates will have punchmarks on them to indicate the outside. Unsure if the balls on the pushrod are different sizes but have been caught out with this before (can you tell??) and have also had a really draggy clutch simply caused by the friction plates back to front.

The big PITA is that you don't know if you've fixed it without putting it all back together and trying it. On my trials bikes they all had locked up clutches, I still put bikes in 3rd and rock them out of habit if they've been parked up a while, as trials machines tend to have very big clutches they squeeze the oil out and bind by design. But yours does sound like a reassembly issue to me.

Maico490 · Nov 5, 2018

Somehow previously you had the only Beta in the universe which didn't have a dragging clutch.
Plenty of bedtime reading here: https://www.trialscentral.com/forums/topic/28407-the-beta-clutch-fix/
My '08 250 is slightly better after following the instructions but still needs freeing off from cold

wasted years · Nov 5, 2018

Maico490 said:
Somehow previously you had the only Beta in the universe which didn't have a dragging clutch.
Plenty of bedtime reading here: https://www.trialscentral.com/forums/topic/28407-the-beta-clutch-fix/
My '08 250 is slightly better after following the instructions but still needs freeing off from cold

We had another go at tonight but no different,looking online there is a shim /washer that goes behind the clutch basket and it says on the advert if it missing or worn it will throw the clutch out .
Even in top gear it wants to drive so there is something fundamental.

Mursal · Nov 5, 2018

The link in my last post, are they using ATF?

wasted years · Nov 6, 2018

Mursal said:
The link in my last post, are they using ATF?

We had ATF in it before , it worked well, ATF in now and dragging in every gear.
Going to check presence of shim behind clutch basket, can't remember it .

Grassman · Nov 6, 2018

wasted years said:
We had ATF in it before , it worked well, ATF in now and dragging in every gear.
Going to check presence of shim behind clutch basket, can't remember it .

Most have quite a thick flat washer behind the basket. I recon you have put something in the wrong place.

Grassman · Nov 6, 2018

Beta clutch is quite straightforward to deal with. Some other makes can be very troublesome. Gas Gas for 1. It has different design. A Belleville spring is used. They have critical measurements òf the components or the clutch is horrible. Beta is far easier to work with.

Maico490 · Nov 6, 2018

Maybe 3 and 10 have got mixed up

wasted years · Nov 6, 2018

Haven't been back to it yet, maybe tomorrow night.

wasted years · Nov 7, 2018

@Maico490 , @Grassman , you weren't far away, couldn't recall putting the flat washer on behind the C/basket so took it back to bits and its missing.
Lifted the plastic pallet up off the floor that I use to put bits on and the git has fallen off underneath it.
Back together and working right, happy Dad, happy child.
Thanks for the tips everyone.

Any motorbike clutch experts on here?

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