[Dingo Dan]

Hey Maties, I am rebuilding an incomplete '52 Speed Twin and am ordering parts to complete the motor. I expected to find a cush drive on the end of the crank and that is what the manual told me to expect BUT there is no capacity to acheive this! I thought Oh ho I have a '55 Tiger Crank Shaft which makes sense BUT the 55 is threaded on the end to take a nut and mine is drilled and threaded horizontally to take a bolt! Does that ring any bells with any one? I need to know so I can order a spacer/washer/bolt to hold the sprocket in place.

Thanks

Dan

 

[bobscogin]

Can't you install a stud in the end of the crankshaft? Your Speed Twin was originally fitted with a compensator, the Tiger was not, but the crankshafts are the same. The factory used a "distance piece" (spacer) in place of the compensator sleeve when the compensator wasn't fitted.

Bob

 

[Dingo Dan]

Thanks Bob, I hadn't thought of a stud. WOuld you suggest installing a cush drive or just the spacer?...there is no cushion in the clutch. Thanks to fouracewes I know the stud is a "7/16ths x 26 threads per inch, both sides"! Gotta love these forums

Dan

 

[bobscogin]

Thanks Bob, I hadn't thought of a stud. WOuld you suggest installing a cush drive or just the spacer?...there is no cushion in the clutch. Thanks to fouracewes I know the stud is a "7/16ths x 26 threads per inch, both sides"! Gotta love these forums

Dan

If you can round up the compensator parts, that's the easiest route. I think the compensator was discontinued when the rubber cush was added to the clutch. Alternately, you could fit a later clutch hub with the cush drive.

Bob

 

[reverb]

...hello man, I have a 48 with the compensator. You need the cushioning not matter what of the two systems.
I have the 48 parts book that I think has the same numbers that yours have if you are in the need, however I do not know any vendor that have them. The coil (spring) and the part with the splines, the other part is easy to do in a lathe.
May be its easier to do what Bobscogin says

 

[bobscogin]

The part number of the "distance piece" you need when eliminating the compensator is E-3384, new number 70-3384. A quick search shows it to be readily available. Or if you can get the length, have a lathe and can cut a keyway, you're home free.

Bob

 

[Dingo Dan]

Thanks for the facts Bob, much appreciated. I'll do a search on the boards for this but you might know, am I better getting an original iron barrel and head for a '52 crank case or go with an alloy barrel and head? They do fit right? I like the look of the alloy but am after a fuss free option!

Dan

 

[Dingo Dan]

Thanks Reverb, I am thinking of going down the Bob path of a distance piece and a later clutch. I got the parts catalogue for the '52 (ain't the Intranets great!) but finding the right part for the end bolt/stud is the problem...I'm going to settle on a 7/16, 26tpi thread bolt and see i it fits...then the rest can just hang there...would love a lathe...luckily have a freind with one! Dan

 

[bobscogin]

am I better getting an original iron barrel and head for a '52 crank case or go with an alloy barrel and head? They do fit right? I like the look of the alloy but am after a fuss free option!

Dan

The top ends interchange as a complete assembly. When you say "alloy barrel and head" I supposed you mean alloy head, as there is no stock 650 alloy barrel. You can use a complete '63 or newer unit construction top end. Make sure the pushrod tubes are correct for your head and barrel. There were some changes over the years in the way the tubes sealed to the head and barrel, Having the wrong "stack height" will lead to leaks if too short, or damage to the head if too tall.

Bob

 

[Dingo Dan]

Thanks Bob, I have got my hands on a n E2958 alloy barrel for a 500cc motor, supposedly from '52-55 TR5/T100. The question I am asking is will this mate up to a '52 5t crankcase? The head is a 2679 Fine Fin alloy head off a T100/5t so it should sit on the alloy barrel ok and is it just a case of suck it and see for the tubes? or is there a scientific formula for working that out? The thing with the head is it has been modified with a big block of aluminium to take dual 1" bore carbies...Is it worth the hassle? I decided to go with the spacer on the crank and a cush drive in the clutch...simple swap of the centre hub and probable the same cost as a cush drive. Thanks for your input, it is appreciated by this newbie

Dan

 

[bobscogin]

Dan, disregard my previous comment about a 650 alloy barrel. It went right over my head that you were working a a Speed Twin and not a 6T. My experience is with the 650 models, so I'm not sure if the alloy barrel will fit the 5T crankcase, but knowing a little about Triumph's fondness for interchangeable parts, I would think the answer to be yes. There are varied opinions, on setting up the pushrod tube seals. One method is to assemble the head to the cylinder, check for up and down play of the tubes, and select seals that allow about .060" compression. There's a lot of Triumph guys on here that are more knowledgeable than me. Hopefully they'll check in on the subject.

Bob