Weird XS engine part needed - help please

[650performance]

I am rebuilding an early, pre-1975 256 series race engine and the crankshaft cam chain sprocket is in bad shape. Yamaha no longer "supports" this bit.
The Yamaha part number is 2561154900. It is a press on sprocket and looks like a smaller version of the sprocket on the camshaft.
If anyone has a new one (!), a used one on the shelf, or if you have an early crankshaft that is apart and the sprocket is in good shape and can be removed without damage, I'm in the market.
Please give me a shout.
Craig
Cell: 510-915-0529
Email: ctweeks@aol.com

 

[Tim of DO THE TON]

The guys you want to hit up are Mr Riggs and Punkskalar (Hugh's Handbuilt). They both rephase cam shafts and I think fairly often come across 256 camshafts that they press later model sprockets onto, as the 256 cam is 'hotter' than the 447 and therefore desirable for later model rebuilds.

By deduction that tells me they might have some spare 256 sprockets kicking about.

 

[650performance]

Good idea, Tim! I'll check it out.
Thanks,
Craig

 

[5twins]

Yes, but those are cam sprockets, not crank sprockets.

 

[650performance]

Tim's email raised the hope that someone had an early crank that was apart for rephasing and they made a decision to upgrade both sprockets so it becomes, in effect, a later 447 engine. If they did that, then they'd have an extra 256 crank sprocket available.
Or, someone may have a junk early crank that couldn't be easily rephased and replaced it with a later 447 crank in good shape. I'll take anything at this point.

 

[Tim of DO THE TON]

Ahhh... sorry - my mistake. I read the post too quickly and thought we were talking about the camhsaft sprocket.

I've never heard of anyone replacing the crank sprocket. Hugh might be your best bet still as he is taking cranks apart all the time and might have a couple spare bits around.

 

[Punkskalar]

No 256 Parts at this time, we've used them all - shame too... I like those early long rods