FMF Expansion Chamber Exhaust install.

GoldenMotor.com

huckersteve

New Member
May 20, 2008
205
0
0
Seattle
www.gohuckyourself.com
Sure, I have 2 coming now.. I'll mount the stocker on my 29 for familiarization, and diddle the extra.. Jugs are cheap.. And this motor is just dyin to be dinked with! Cheap hobby, and fraggin a few motors is always fun, yes? I haven't gotten mine yet, due sometime this week.. When I'm not here reading threads, you'll know they have arrived, lol! I'm already getting an idea of what I'll do with it.. Gettin it set up with a small Mikuni & K/N will be early on the agenda.. Adjustable ign timing will be top on the list as well, possibly new ign system.. Shave the head, blend chamber.. Weld up a pipe, (first of many) LOL! I'm doin this for kicks man! Its all part of the fun for me, lol!

Yo Tall Tommy where in WA are you located? Tyreslider and I are in the Seattle Suburbs, he north, myself South. We're both happy to help you mod/tweak/grenade your bikes anytime. Hit me up so maybe we can all get together for a cruise ride soon..
 

PaulFlorida

New Member
Dec 4, 2009
52
0
0
central florida
I just took my bike out tonight for its maiden voyage with a ported jug. Like five months ago I toasted my first motor. It came with a defective jug. I bought a jug and read up on porting as much as I could. I posted a bit then about what I did to it, but without pics, it isn't very helpful to anyone. Only a week ago did I buy a new motor. Ran it stock 20:1 for three gallons. SBP shift kit. Slowly got faster every tank. My dad drove next to me in his truck; said it does 34mph until I hit uphill grade. Put my billet intake on it, and had to drop the needle all the way- it ran rich! Later I added my SBP pipe, and that really woke it up. The intake lets it rev quicker, and the pipe adds more torque. I could cruise at 39 on flat, but never dropped much below 32 on mild grade. Wind resistance still limited speed. The jug made it a new machine though! Maxed out my gearing right to the top. Revs much higher and more freely. Pulls top gear right on up.
 

PaulFlorida

New Member
Dec 4, 2009
52
0
0
central florida
I know the porting fad is over, as it just turns the motors to time bombs, but I never knew until today how fun they can be ported. I raised the exhust 2mm, widened it 3mm. It is larger than the pipe flange I.D. and leaves only a small gasket surface. I widened the intake 3mm, lowered it 3mm and raised the top of it 1mm. It is larger than the beveled C.E. intake by 0.5mm all around. There is very little gasket surface now. I removed 10mm from the bottom of the cylinder walls at the transfers, and opened them up as much as I could. It was hard, but I reshaped the transfer ports. made them 1.5 mm wider, and made the top edge nearly square. The top of the transfer port is tapered stock. The goal was to have the fuel come directly across the top of the piston and collide in the center to aid turbulence. I then used a thinner base gasket to lower the jug .35mm and boost compression. I have a dome piston and a slant head on this motor. After I put some miles on it, i'll post about reliability. I'm doing this for fun only, and I'm well aware of the various opinions about messing with port timing. It works!
 

Dogtown Burner

New Member
Sep 15, 2011
349
3
0
Los Angeles
Here are some pics of the pipe on the bike, it looks really cool and I get lots of compliments or hear people say " wow what a sick looking bike !!!"







that's what a pipe is supposed to look like. I'm surprised you're the only guy on here to have done that. I would have thought a KX 60 pipe would better fit displacement for port timing, but if the shoe fits... dang man, I bet it sounds awesome and pulls hard. that was the one area my old KX 80 blew doors on all my friends CRs and RMs back in the day. off the line/outta the berm torque from a great pipe/jet/displacement setup. id love to see this video promised.

rock on!

-Dogtown