Even though this is a quad I figure i’ll still share the build.
'06 Brute 650 SRA
Mods Four Stork Tech Big Bore Kit.
-FST 665 kit, 82mm 11.5:1 Compression Wiseco Pistons
-FST st2 cams (trail/race)
-HD valve springs
-Full Muzzy SS exhaust with equal length headers
-Dyna CDI
-Innovate Wide Band
-UNI Filter
-Rox Handle Bar Kit
-Duro Power Grip Tires
Going to try to not pull motor for the build. Next step is to clean motor to get ready for teardown. Plan is to be done in 1-2 weeks. Taking my time, plus cylinders will be out a few days for boring. Stock hp is 41-43hp, should be around 70-75hp after. Should be a huge surprise for my buddies with 450’s.
Not trying to thread jack, but would you have any interest in these wheels as part of your build? Not even sure if they would fit? I still have them for sale and they are pristine. Will definitely be watching this progress.
naw I’m staying with stock wheels. I’m not even sure if they are the same bolt pattern. Besides I have almost 2k in this build so i’m done spending money on it.
I’m always down for ridding, it will be fun to see how we do.
I’m up in the air for clutching. My old man uses this for plowing in the winter and I don’t want a high stall. I might send it off a guy called VFORCEJOHN that does all kawi clutch’s. He shaves the sleeves and sets up spring rates. I do have a few options for pulling some more power out of this set up. One is called the crossover mod where you use a 3/4"-1" pipe to connect the intake boots. Jetting can be tricky and i’d have to change out to a electric fuel pump. That’s usually good for 5-7whp. Plus you can always drill holes in the intake cover.
Tonight’s plan is to drain oil and coolant and start pulling motor apart. I want to get cylinders to motion craft tomorrow. Tomorrow Ill lap the valves and install hd valve springs. This is of course if everything goes as planed. Hopefully saturday I can start reassembly. I still have to get the O2 bung welded for the wide band.
Pic of crossover mod
New toy for garage. 125000 btu heater. Set for 60 and get to work.
Top end is off. Dropping cylinders off tomorrow.
Zac i’ll look into the valve seats. This is a kawi motor that suzuki/arctic cat used.
Plan is to start reassembly Saturday. Top end should only take 2 hours but it will take all day to get it back together.
MTX-L Can get it off ebay for $160. All in one unit, hook up power and ground and its ready to rock. Water Resistant so it’s perfect for quads, sleds, bikes. http://www.innovatemotorsports.com/products/MTXL.php
I was looking at the heads last night. Front is perfect, intake valves are black and exhaust are brown. The rear head has me thinking… Intake valves are good but the exhaust valves are in question. One is brown/whiteish, the other is black/brown. I’m not sure what is causing that, maybe its because the exhaust pipe doesn’t come strait out. Ill have to take a pic. Any ideas?
---------- Post added at 08:30 AM ---------- Previous post was at 08:23 AM ----------
In red is what I’m talking about with the exhaust.
alot of motors dont run exactly the same on both cylinders…due to variables such as exhaust length/shape differences. my boondocker fuel controller has a trim adjustment for the pto side as it typically runs richer if you add twin pipes on the cats.
in your case it is probably due to the length and shape of the exhaust as it flows…theres a difference in backpressure and velocity that is causing it to run different. in that one being a lighter tan and brown instead of black and brown…the backpressure is actually making it perform at a better “tune” compared to the other cylinder…
example- the 2010-11 arctic cat 800 ho motors produced almost 10hp and 10ftlbs more power in the midrange compared to the 2012+ procross chassis even though the motors are identical. the different exhaust shape and quieter(higher backpressure) muffler on the 10-11 was the reason for this. when a 2012 was on the dyno a 1.5" x ~2.75" tube with a flair was set in the muffler where the expansion pipe sets on…dyno showed about +7hp gain and +5-6ftlb gain in the midrange…all from backpressure. 4 strokes are affected in the same way…the only time you really dont want any backpressure is in a FI/turbo situation.
yeah I know what you mean about each cylinder running different. Just weird that the two exhaust valves on the same cylinder were different. I did have issues with the intake boots. They were cracked and making it pop and run lean for a bit. Got new boots and it ran great.
Couple pics after I got the top end off. I’m really glad I didn’t have to pull the motor.
If you guys have any ideas to clean the mud/dirt stains off the motor speak up. Sucks how it gets baked into the aluminum.
Not much to report. Cylinders are at motion craft. Dropped of exhaust collector to my buddy so he can weld the O2 bung.
If anyone is interested in these itp mud lite XL’s. I got new tires so I don’t need them. Back are 25/10/12 with 3/4" tread and front are 25/8/12 with 7/8" tread. Plug or 2 in the back tires, have to top them of once in a while. They are very lite.
$150 obo
