A65 crank

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I am trying to remove the crank from an A65 with middling luck. It appears that the crank bushing has bound up on the crank. The usual 3 jaw tool for Nortons and Triumphs ...the jaws will not between the gear and bushing without really thinning them which will also weaken them. The crank will not turn or go right or left. It will not budge even if I were to take off the gear. Would it be advisable to heat the case to approx 250 degrees and drive out the bushing and crank together? I will still have to thin out the jaws but it seems I can get another set for $23.
Also...I removed the left case and found a thin sheet metal cup washer between the crank bearing and the crank. I see no use for this but does anyone know why it is there? The roller bearing appears to be the original.
 
The washer you found is probably the shim retaining cup washer 68-0638.

I would give it a go, your plan of heating up the crankcase. A kitchen oven has my preference. The crankshaft is a nice "pulling weight".
 
I will need to get a helper for the heating and separation process. Thanks for the picture from Draganfly.
A new question has come up...what are the bearing shells pictured? I am used to either shells or a bushing. Can you explain the shells?
Also, what worries me is that the bushing is made of bronze and will expand about the same rate as aluminum, making the heating process less in my favor than if it were a steel bearing. Still I have no other way to go. I was handed this motor to "unstick" it. The owner built it, claims it ran briefly, and locked up tight. I slowly ruled out all other possibilities and concluded the crank has seized on the bushing. This seems difficult to do but I am not familiar with BSA motors. In their favor, I really like how the transmission can be pulled out in one lump and also that BSA built in an excellent spot to insert a screw driver to separate the cases. Five thumbs up for BSA. Triumph is a major headache to get the cases apart.
 
Which year?




A65 crank
 
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If the bushing wasn’t reamed correctly I could see it seizing on the crankshaft easily. Maybe ask the owner if the bushing was resized after installation or if the clearance was actually measured.
 
I pulled outthe bushing but have not separated it from the crank. It appears that the bushing is bronze inside a steel outer cylinder. the small holes in the steel do not line up with the bronze so there was no way for the oil to reach the crank.
 
I pulled outthe bushing but have not separated it from the crank. It appears that the bushing is bronze inside a steel outer cylinder. the small holes in the steel do not line up with the bronze so there was no way for the oil to reach the crank.
The bronze bush should be pinned to the metal housing
When they are not pinned the bush can creep and close off the oil
That's my memory of it from 40 odd years ago
 
That bush is a weak point if not sorted initially and an eye kept on oil changes later. I think the real problem
was that the crank didn't have end feed. Oil flow is working against itself and when the crank is worn the OP
heads south.
Any pictures?
 
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It would be a delicate operation to pin the bronze to the steel backing. I like the idea of a solid bronze bushing. This is a customer's motor, will talk to him later this week.
 
It would be a delicate operation to pin the bronze to the steel backing. I like the idea of a solid bronze bushing. This is a customer's motor, will talk to him later this week.
The solid bronze ones are the best , the metal backed pinned bronze ones are ok
The non pinned ones are the worse
The devimead/SRM conversion has to be the best if the bike is going to be used all the time
Although I once had a chat with Dick Rainbow of rainbow motorcycles about the conversion as he raced A65s and he threw a fit saying there is no need for it,he said the bottom end will last a 100,000 miles if you change the oil!
 
If it has proper clearance including end play at rebuild time. And I agree with longevity as most of us are long in tooth.
 
In any case, I found fitting an oil pressure gauge reassuring.
Easily done and doesn't cost much.
Gives you an idea of wear of pump and bearings over time.
Let alone low oil level in tank.. :oops: . Saved me an engine.
 
I have an oil pressure gauge that is quick and easy to install on Nortons. I use it often to double check motors and it has saved several motors. I have found three heads with the spindles in backwards, among other problems.
 
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