just wondering what kind of compression you guys have in your blasters.
i have 155lbs. thanks

 

Mine is 225psi.

 

what have you done to you motor that you have 225 psi?

 

225 psi!! holy crap! There is no way in hell you have 225psi of compression.

1. You'd have to run about 170 octane race gas - good luck finding that!
2. the cyl head would be shot through the gas tank
3. good luck starting it, you might want some lead shoes

I'd believe 225 if it was kpi, but 225 psi is scary!

If you want to imbellish your compression, try something reasonable.

BTW: I have 125psi.

 

I millled the head down a significant amount. I also milled the bottom of the cylinder down because their was a gouge in the bottom that cylinder that came from the previous owners rebuild. I milled that because the bike was poring out gas and oil through that gouge. By the way I do run hi-fi race gas from F&L fuels, and my compression is 225 and it has wasted every Blaster I have encountered.

 

Hey, how much did that cost? Was it with the stock bore?

 

What items do you want a price on? The 240 Kit I put on I did my self as well as the milling(friend owns a mill and a lethe). The stock bore is 66mm and the 240 kit is 72mm.

240 kit: $292 installation is around $120

P.S when you do the 240 you will also have to buy a carb. I have a 38mm Mikuni flatslide, and a manifold (I made mine)

 

I just got through milling the head on my 240 blaster, I milled the head.080 for a compression of 195 lbs, so it can definatly be done and you only have to use 110 octane to let it rip. I personaly think that milling the head for comp. is a great way to extract alot of power!
it has my blaster going nuts! but I am still wondering what my new compression ratio is? does anyone now the formular to figure this out?

 

Yeah, that's what i'm wondering. If stock is 6.6:1 and with 185lbs. you have to use race gas so it doesn't detonate, the compression ratio has got to be pretty high. Because on 125's and 250's (dirtbikes), they have compression ratios from 8:1-10:1 stock, and they don't have to use that high octane gas, i don't think