Clutch springs A50

[AdrianS]

Further to my last post re clutch lock washer, I now have a further clutch question.
The existing springs are old and I did wonder if I was getting a bit of clutch slip.
I am having trouble getting new ones. The ones I took out were about 1.5 inches long with 8 coils of wire.  All the replacements I have looked at are the same diameter, same wire gauge , but have 10 turns and are about 2 inches long. I cannot get them to compress enough to get the retaining screws on.
I cannot find any replacements, would it be reasonable to cut the new springs down to the correct number of coils? The only problem I can see is that the original springs had half of the last turn tucked in to make the coil seat flat.
Any other suggestions?

[DAVE BRADY]

Hi Adrian,

SRM have them for the 3 spring clutch and I have just had some and they fit.  They do need bit but not excessive amount of pressure to get the nut to start but I believe that is how they should be.

Dave.

[AdrianS]

Cheers Dave.

I have been looking at various clutch springs form different suppliers. Its a shame they don't all list the dimensions so we don't end up buying the wrong parts. It appears that Triumph early 3TA and 5TA springs probably fit. They are 1 1/2 inches long and 41/64 inches in diameter which virtually matches what my existing springs are. ( They are a tad shorter as they are worn).

Will also give SRM a ring and have a chat with them.

[Mike Farmer]

 
The originals were 39mm. most of the springs being sold now are about 42mm. thats almost 10% longer. I actually cut one turn off and the fit now is OK and not necessary to use excess force
Mike

[AdrianS]

I think they are longer than 42mm - nearer 49/50mm

[Bess]

Hi,
     Here is the original specification if you wish to try again to source them. I guess cutting what you have to get as close as you can in the meantime, is the next best option. I suggest putting the cut end at the bottom of the cup as the fasteners have a raised area which butts up against the manufactured spring to stop them from loosening.

Best wishes...

[Mike Farmer]

 

First of all apologies for the garbage I posted recently about clutch springs. I cant even find where I got that info from. Probably the Beano

Hi Bess I found out the hard way about which way up to put cut springs. The cut end dug into the rear of the clutch nut and made it impossible to turn. I had to drill through the nut and then push a small screwdriver through the hole to push the spring clear. Then hold it there cos every time I turned it, it jammed again.

Live and learn

Mike

[AdrianS]

Hi,
     Here is the original specification if you wish to try again to source them. I guess cutting what you have to get as close as you can in the meantime, is the next best option. I suggest putting the cut end at the bottom of the cup as the fasteners have a raised area which butts up against the manufactured spring to stop them from loosening.

Best wishes...

The info is for a 3 spring clutch. Mine is a 4 spring clutch. The old springs were just under 1.5 inches long and when fitting still had to compress the spring a bit to get the retainer to bite.
Very early Triumph 3TA and 5TA springs seem to be the correct spec. All the new A50/65 springs seem to be just under 2 inches long and there is no way they can be compressed to fit into my clutch.
I believe there may be different spring cups available to accommodate different springs but mine are quite shallow.

[Bess]

Hi,
    Here are the 4 spring specs part number 68-3236, Mike you were right for the 4 spring system.

Closest here: https://www.classicmotorcyclespares.com/index.php/default/clutch-springs-early-4-spring-bsa-triumph-unit-preunit-t999-42-3273-68-3236.html

Maybe worth giving C&D Autos or Kidderminster a call?

Best wishes...

[Mike Farmer]

 

Thank heavens for that. I thought that I was going around the twist. Mine is 4 spring. In fact I checked one of mine a bit earlier and they are brand new and definitely 42mm. The same ones that I cut for other machine.

Incidenely the ones that I cut went in very easily but still hells stiff on the lever. I reckon they are at least 20% over strength. I'll see if I can get them checked(or how do I check them)

Thanks for input Phew.

Mke

[Bess]

Hi Mike,
            The spring for the 4 spring clutch states 90lb/inch, so put 90 lbs. on it and it should compress by 1 inch.

Best wishes...

[Mike Farmer]

 

I seem to be doing more stupid than ever. I've just seen it says 90lbs/inch. SFB (S--- for brains).

Mike

[AdrianS]

As I said, early Triumph 3TA and 5 TA springs.

[Mike Farmer]

 

Assuming you used the Triumph springs, what are the measurements.?

Mike

[DAVE BRADY]

Hi,

SRM have 5T clutch springs on their webshop.  Well worth giving them a call or as mentioned C&D Autos.

Dave.