One for the porting gurus.

[simon998]

I was rifleing through my spares and trying to throw together a decent engine for the baby elsie. When I was trying to pick a decent barrel, I noticed this one had been ported.















How does that look to you? I know knife edging is a no no these days but it isn't too drastic but I don't understand why holes have been drilled from the inlet to the transfer ports.

The inlets been raised and widened, and I think the exhaust port has been raised. Compared to a stock barrel the exhaust outlet is a good bit bigger on this one.

I'm thinking about getting it honed, matching a piston, tidying up the porting job and seeing how it runs. If it runs like shit I've 3 other barrels there that havent been touched.

[midlifecrisisrd]

The extra inlets are a good mod

Even Yamaha did it on the 51L rz250 ypvs

Run them and see as does not look like a diy job

Steve

[markhoopy]

When I had the barrels tuned on my 350 YPVS the same thing was done with those.
It runs really well so certainly not a bad thing to have..

[simon998]

Excellent news. I had thought someone over the years just butchered them. The barrel is currently at 56.25mm, so it's only on its first overbore.