A new heart for my beast

[Muddy200x]

I decided to build an entirely different engine rather than mess with the one that I'm currently running. (might need it in case things go bad) :eek:
It's a 1991 xr200r bottom end and rocker box, with a 200x cylinder and head. Going to do a nice port and polish job to compliment the 31mm mikuni carb. This thing is going to be built as radical as I can get it. Minus NOS
I have never built an engine so this is going to be a learning process for me. Luckily I have a friend who has built many 200x's, so I wont have to plaster the boards with a lot of questions, But I would appreciate any advise.
I'm going to be buying the high performance parts soon (piston,cam,oversized valves, valve springs) Probably going to go with a powroll kit. But still undecided. Also unsure what size sprocket I'm going to need to compensate for the XR gearing.
Well, anyway here's a pic of what I got so far. I already got the side case and complete kickstart assembly just not installed yet.
http://members.aol.com/_ht_a/muddy2OOx/images/dscf0533.jpg

[ATC crazy]

She looks great. Good luck with the installation...and get some pics when the sugery's done :beer

[trikerider2oo7]

looks good...are you going to change the direction it kicks so that you dont have to cut the fenders?

[Muddy200x]

looks good...are you going to change the direction it kicks so that you dont have to cut the fenders?
Yepp, already got everything that I need to do that. but before I do it Im going to get the side cases powdercoated.

[3WheelsForever]

Looks awesome Muddy. You may have to make the intake tube longer otherwise the carb may not fit in between the frame and shock like its suppossed to. Id use a 13 up front with a stock 40 rear.

[leprogle]

how can u change the direction of the way the kicker goes?

[Muddy200x]

Well, I haven't actually done it yet, but its seems pretty straight forward. You have to replace XR the inner kickstart shaft with a 200x shaft. and ad a 200x sidecase, gears and kickstarter. There almost the same engine and luckily the side cases are interchangeable.

[samster143]

I am running 13-38 for gearing and want to drop 1 in the rear. Has terriffic acceleration but could a little top end. I have a 27.7mm carb. I think a 31mm may be a little big, it may be tough to get it all jetted out right. Powroll may be able to provide jet specs. Are you going for the Stroker kit?? I have been wanting that for a while now along with the 12:1 piston. What cam will you use? Keep us posted with your progress.

[yamahaman89]

looks GREAT!!!

[Muddy200x]

As of right now the plan is to go with powrolls high compression premium kit. but due to costs it going to take a little while. Stroking the motor is a must, I just hope I don't rip out the gears. I'd feel a little better stroking a 5 speed rather than a 6 speed, but oh well. thats why im saving the stock motor.
Its going to be interesting to see how the carb works out. The guy I got it from had it on a 84 and the only mods done to the engine was that it was bored 40 over. he said it worked and the reason he took it off was because his son had gotten hurt on it so he was selling everything. But man that carb looks huge on it. I test fitted it to my stock motor and it fits well. I just need to find the correct throddle cable.

[samster143]

Motion-Pro can make cables to fit pretty much any bike/carb/throttle. They have a website and it has thier tel #. Ask for 'armor coat' is looks like/maybe stainless steel!

[Glenn J]

Looks nice, keep us posted and take lots of pics. :cool: