RM 250 tuning

[Torna]

Hi. I have been driving my RM 250-03 for almost a year now. I have started to get used to the power, so I am planning on getting some additional ponies in the low to mid range of the powerband.
Is it anybody who can adwise me what kind of reed valve and pipe I shouled go for.
Is Boyesen Radvalve better for me than Vforce3 valvs?
What pipe is best. Bills Pipe, Procircuit Works pipe or FMF STS pipe????
Is it anyone who has experience of Power Blades. (That devides the intake of the carborator in two parts).
To be honest I really dont need more power ( My son is faster with his 125 KTM). But more power is more fun!
Best regards Stefan.

[Louis]

Hang on, we don't have that many members with dirt bikes around here. Might take longer but hopefully someone can help you.

[Dave2122]

You can run the FMF pipe for Low and Midrange (Pro Circuit is mostly upper mid and top end). I like the Rad valve but to be honest I have never used the V-force cage so who knows. You can run the thinner 2001 headgasket to bump compression or run a weisco piston with a slighltly higher compression. Clean and match the cases and gaskets and knife edge the tranasfer ports. Run the shortest silencer you can get away with and yous should be making some decent power. I am amazed you want more as my 02 right out of the crate was an absolute monster of a motor!

[Torna]

Thank you for your adwise. Actually FMF and Boysen was what I had in mind. I dident know about the thinner gasket, but that sounds interesting. My englich is not so god, I did not understand what you ment with; and knife edge the tranasfer ports.?
In the begining of the season I really had some problems to hang on to the handelbar, I was saved at severel times by a finger on the clutch!
Best regards Stefan.

[ALLEYCAT50]

Make sure that you can by 100 octane or better at the pumps.

I can only by 91 octane here and had to lower my compression by adding a second base gasket, and jetting was a nightmare.

Knife edging: if you look at the bottom of your cylinder there are ports that bring fuel mixture to the top of the cylinder when the piston is on the down stroke. In the centre of the ports is almost a wing, you want to narrow these where they start, a bit so they start "knife edged" and taper as the port gets deeper. Take as little as you need to, you are just trying to get the mixture to flow smoothly.

Also I found in my 2003 that the ports had huge burrs(sharp edges) in almost all of the ports, clean these up, but don't hit the inside of the cylinder.

I just used a $20 rotary tool with a flexable attachment for porting, worked great.

I put a v-force3 block in my bike, I was not disapointed, but stock with a good set of reeds would have been just as good in my opinion.

Hope this helps. good luck.

[Torna]

Thank you now I get it. I ´made this operation on my YZ 250 I did not have a router so I grinded and poliched everything by hand. It took me three long evenings, but it was well worth it.
Best regards Stefan