The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Gearbox, Clutch, Primary => Topic started by: petetherev on 23.01. 2015 19:29

Title: Clutch Plate Insert Thickness
Post by: petetherev on 23.01. 2015 19:29

Hello everybody,  can anyone tell me the thickness of the Clutch Plate Insert for the Six Spring Clutch please. Mine are only about 0.150", which seems a bit on the low side to say the least.

Thanks
Regards
Pete
 

Title: Re: Clutch Plate Insert Thickness
Post by: bikerbob on 26.01. 2015 08:26

My 6 spring clutch only has the inserts in the clutch basket and I have an old spare one with worn inserts and they measure .149. I tried to buy new inserts but could find no one who stocks them and had to buy a new clutch basket complete quite expensive  if I remember it was about £80. With yours measuring only .150 I would say they are well worn if they are in the  clutch basket.

Title: Re: Clutch Plate Insert Thickness
Post by: Butch (cb) on 26.01. 2015 11:41

Ha - I was checking the magnets for the alternator in the back of the clutch drum on my Sportster at the weekend and found they had commenced their destruct sequence. £440 is the best UK price I've found so far, hoping I can get one flown in for less.

Title: Re: Clutch Plate Insert Thickness
Post by: duTch on 26.01. 2015 14:36

 I have some NEW (Surflex I believe) plates from DragAnfly, and they measure on average ~ 0.0147... (0.01455-0.0149ish) .!!!

Title: Re: Clutch Plate Insert Thickness
Post by: petetherev on 29.01. 2015 20:07

Hello All, thanks for the replies.  I found out that Dragonfly had inserts on their site and quoted the thickness as 7/32" (0.218").  I didn't know if the included a sanding allowance, I assumed not.  I actually bought some 6mm cork sheet (450x300mm for £5.35 on e Bay enough to make 450) and made my own. I made a template slightly larger than the hole in the plate, it took about 3 hours to do the lot.   6mm is too thick as it will not allow the plates to fit in the confines of the chain wheel and basket. I think 5mm will be too thin not allowing for any sanding.
  I have now re-corked all my friction plates and sanded them to 7/32", this gives 1/16" protruding each side of the plate, and they fit just about right. I did not realise at the time but the inserts in the chain wheel are thicker I'm going to make them 3/8" allowing 1/16" as I did with the others and see what happens. Either way I won't be far away.
I'll post the result I have  tried it out, I'm assuming that as it is new cork it will settle in time under compression.
Regards
Pete