Mid eighties CR 250 type Boyesen,anyone tried??

[jvb]

 

[jvb]

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Sorry ,had to post it in a different category i think and i don't know how to delete this
Anyways i'm defenitely trying this in the future,need a spare motor first

 

[OConnor Racing]

You need to be very careful with the size of those ports with a Blaster cylinder. I did one for myself a few years back and posted some pics here. I'm pretty sure it was my first +6 mm build. It made a huge difference and ran like a scalded dog. The problem was, it only lasted about 30 minutes before the back of the cylinder broke. If I did it again, I would build up the area over the rear tabs. Something like a CT cylinder.

 

[jvb]

You need to be very careful with the size of those ports with a Blaster cylinder. I did one for myself a few years back and posted some pics here. I'm pretty sure it was my first +6 mm build. It made a huge difference and ran like a scalded dog. The problem was, it only lasted about 30 minutes before the back of the cylinder broke. If I did it again, I would build up the area over the rear tabs. Something like a CT cylinder.

Thanks for the info.should defenitely reinforce backside of cylinder.
And maybe bore out the casted headstay mount , and attach it with motor mounts to the frame like dirtbikes?

 

[OConnor Racing]

It's not a bad idea and wont hurt anything.