Britbike forum Forums Thread Like Summary - CB34 engine bits

Hello fellow Gold Star owners! I'm getting some parts together for my CB34. The top end on my bike has a worn piston. It still has the Oval crank. I have tried reaching out to Phil Pearson with no luck. I do have an old email direct to him, but was trying to use his new business address. From my research on this forum, His business address is now at the website bsagoldstar.bike. I have tried that site and sent in an inquiry, with no response. So website shows a listing for an NEB crank. that's not the same as a Pearson crank is it? I am not on Facebook so I don't know yet that is the valid site. Can any of you comment?

Alternately… since the engine on this bike has the oval flywheel, Would it be worth considering simply changing the conrod to a Carillo and call it a day?

Another thing about the engine on my bike, is that it has a M20 timing cover on it. It does not have the rotating breather. I was able to find a timing cover as spare with the quill on it so I'm partway to having the right breather setup. If I was considering pure function, is it worth it to get all the rest of the bits to complete the stock breather setup? I could just go with a reed breather. Please, let me know your opinions if you have them.


Thanks for your time and attention. And thanks to Microsoft for voice to text. I am using that system right now because I have two broken wrists after a highside get off on my Moto guzzi.

To be correct..

N.E.B is N.E.B and “Joe Maxwell Engineering” is NOT a producer for N.E.B.

Joe is a Dealer/re seller of N.E.B, so is Phil Pearson jr. and so does my company ;-)
The crankshafts for Goldstars are excellent products, as are their clutches…

In case it helps, the photograph shows the relevant dimensions from my Pearson crankshaft.



The length of the 'nose' isn't well defined because of the neighboring threads, so the length from the flywheel face is what I would use if I were machining a nose to replace the pipe in an older-type crankshaft since that length determines how far into the timing cover the nose will stick. I measured the lengths with a caliper so they're ±0.001", but the diameter with a calibrated micrometer so it's ±0.0001". I used the shanks of drill bits to measure the ID (a #20 fits so it's at least 0.161", but a #19 doesn't so it's smaller than 0.166"). I could measure it more accurately but the precise diameter isn't critical so the drill bits should be good enough.

Let me know if there's any other measurements or photographs that would help your hands-free engine assembly.

Attached Images

Hey Kevin,
Is that you on the cover of the March 2022 Piled Arms, on a Gold Star?
Looking good if it's you, or even if it isn't you.

If a DBD head/barrel can be plonked directly on a set of B31 cases without modification, I'm sure the same can be said for CB.
Just ignore the extra tapped hole in the bottom of pushrod tunnel

Kevin: As for the stud sizes over the years the top end had two different sizes going into the head depending on the model but the bottom end that threads into the cases did not change.

Gordo