BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Bigsingle on 21 Jun, 2024, 09:21

Title: Primary cush spring ?
Post by: Bigsingle on 21 Jun, 2024, 09:21
Hi , is there a dimension for the cush drive spring shock absorber,   I didn't have any difficulty just putting the outer crank nut on , should you have to at least push in on the spring to get the thread started , with the cover off when I rev it up I can see it easly move out on ramps and stop , do these springs need to be replaced ?  Cheers
Title: Re: Primary cush spring ?
Post by: Ian C on 21 Jun, 2024, 11:14
You haven't stated whether you have a 2 or 4 lobe shock absorber as the springs are different. AFAIK, the 2 lobe spring (part no. 67-1136) is round cross section wire (plus heavier gauge than the 4 lobe spring) and the 4 lobe is square section (part no. 66-1706). HTH
Title: Re: Primary cush spring ?
Post by: KernowPete on 21 Jun, 2024, 17:22
On my B31 i had to compress the spring in the vice and put some cable ties through it so I could get the nut back on. No idea if that helps at all.
Title: Re: Primary cush spring ?
Post by: Bigsingle on 21 Jun, 2024, 17:30
Quote from: Ian C on 21 Jun, 2024, 11:14
You haven't stated whether you have a 2 or 4 lobe shock absorber as the springs are different. AFAIK, the 2 lobe spring (part no. 67-1136) is round cross section wire (plus heavier gauge than the 4 lobe spring) and the 4 lobe is square section (part no. 66-1706). HTH
Hi thanks for your reply,  I have the two lobe design, I'm sure it doesn't have enough spring tension,  I am not sure which spring it has , I will look into that and see if it foes have the heavier spring .cheers .
Title: Re: Primary cush spring ?
Post by: Steve.S on 23 Jun, 2024, 18:55
It should be difficult to get the nut on, but I doubt if the spring has shortened that much.
Draganfly have the part no. quoted as 1 1/2" long.
Perhaps the sleeve is too long? Maybe a kind member can give you the dimensions?
Title: Re: Primary cush spring ?
Post by: Bigsingle on 23 Jun, 2024, 20:22
Hi , thanks to all I've ordered a new 67-1136 spring and when the cover is off next I will compare it to the existing spring , I can always make a hardened spacer to make it more difficult to get the nut on . Cheers 👍