Commando Fork Damper Info

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Hi
I am currently rebuilding a 1969 750S (as a roadster) and I am seeking information or the sizes of the piston and tube of the fork damper or the clearance between the two.
I know they are still available new, but do not wish to purchase a set just for dimensions as I am experimenting with making all the Bushes, Caps, and Pistons out of Oilon (oil impregnated Nylon) to reduce stiction.
Any and all help will be greatly appreciated.
Cheers
Tony
 
Welcome to the forum, Tony,

The only unused part of those that I have available to measure is the damper cap of which the damper rod bore (damper rod/cap clearance affects rebound damping) is exactly .375" (3/8").
 
L.A.B. said:
Welcome to the forum, Tony,

The only unused part of those that I have available to measure is the damper cap of which the damper rod bore (damper rod/cap clearance affects rebound damping) is exactly .375" (3/8").

Thanks L.A.B you guys have some great content here.
I have managed to get pretty well all the other dimensions from various web atricles, just nothing on the piston clearance. I'll keep trying though.
Cheers
Tony
 
Tony,
I've had a bit of experience with materials like Oilon, during service it can take up moisture/oil and swell. Contact the manufacturer and they should be able to give all the help you might need.

Best of luck.

Cash
 
cash said:
Tony,
I've had a bit of experience with materials like Oilon, during service it can take up moisture/oil and swell. Contact the manufacturer and they should be able to give all the help you might need.

Best of luck.

Cash

Cash
The guy that sold me the material did inform me of this although he could not be precise as to waht extra tolerances should be added to allow for expansion. I infact purchased the food grade version which is less likely to swell. I will machine up the parts and leave them sit in oil for a couple days before I assemble the forks. the top bushes will not be a problem if they are a fraction tight, I can run a reemer through them, the bottom sliders I may have to hand finsh if they are too tight; at worst I will have to start again. Thanks for the advice and heres hoping :D
Cheers
Tony
 
Hi
Well I have reassembled and workshop tested (not ridden) the forks with good results. They work more freely with a lot better action compared with the old steel and phos bronze bushes. I will keep you posted once ridden, thanks agin for all your help.

Cheers
Woolant


Woolant said:
cash said:
Tony,
I've had a bit of experience with materials like Oilon, during service it can take up moisture/oil and swell. Contact the manufacturer and they should be able to give all the help you might need.

Best of luck.

Cash

Cash
The guy that sold me the material did inform me of this although he could not be precise as to waht extra tolerances should be added to allow for expansion. I infact purchased the food grade version which is less likely to swell. I will machine up the parts and leave them sit in oil for a couple days before I assemble the forks. the top bushes will not be a problem if they are a fraction tight, I can run a reemer through them, the bottom sliders I may have to hand finsh if they are too tight; at worst I will have to start again. Thanks for the advice and heres hoping :D
Cheers
Tony
 
Tony
Good to hear, I hope it all goes great cos I've found a bar of the stuff while cleaning out the garage (moving stuff about). I reckon the top bush could be made a bit longer too.

Cash
 
Hi Cash
I did that, made them 1.5" longer. then used plastercene to gauge the stroke length in the top of the damper tube before cutting them off, thus creating a bump stop with the bush also.
Cheers
Tony

cash said:
Tony
Good to hear, I hope it all goes great cos I've found a bar of the stuff while cleaning out the garage (moving stuff about). I reckon the top bush could be made a bit longer too.

Cash
 
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