Ported Polished - 110/93 mix needed??

I'm in the market for a new bike, I have a list of three I'm checking out tomorrow.

'02 YZ250 w/ minor mods.

'02 YZ250 Ported, Polished, carb work, aftermarket reeds/cage, pipe exhaust, etc. This bike was an EBR project apperently ( http://www.ebrperformance.com/main.htm ) and many mods were done.

The first can run on '93 octane pump, but the second has always been run on a 110/93 50/50 mix. Jetting aside, can a bike with porting/polishing be run on pump gas? Once this is done is the bike forever going to need the higher grade stuff, with the exception of putting a stock can and head back on?

Both bikes are very clean, the 2nd is a little bit more but nothing I cant swing. Both owners give me great impressions and a thourough inspection will def. be done before I buy. But if I have to buy 110 the 2nd is most likely not going to happen. Figured I'd ask.

Mike, the need for the race gas is going to depend on the compression in that modified motor. If it was raised over stock, you will probably need the race gas. The stock yz's barely get by on the top grade pump gas as is.

I would buy whatever bike based on condition. Any good tuner can modify the race gas bike to run on pump gas. You will lose a small amount of power, but that is a trade off for running pump gas.

Figure about 50 bucks to re machine the head for lower compression.


why not just pull the jug and put on an extra thick base gasket?

cost would be 15 or so (and time).

^^ Thats a good idea. I have heard of people doing that in years past. If anyone can think of a reason that wont work please add your input! Thanks.

It changes the port timing and nothing good will come of it.

Get the head milled.

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