200x performance mods

[tecate kid]

As I have said in a few other posts I just picked up a 200x, (not sure on the year, don't know how to read SN) I have to rebuild the top end on it before its ridable, but as long as its apart I want to do a couple of mods to make it more powerful. What are the best and most cost effective? I figured a high comp piston (10.5-12.5) a cam, (whats the best grind?), and maybe some head work, (who does that and is good?) Another idea I had was swapping in some XR200 motorcycle engine if those make more power in stock form. Any insight on this would be really nice and greatly appreciated.
tecate kid
P.S. I have a friend with a XR200 that he can't get running after the new topend. So he might sell it cheap.

[ATCWRENCH]

depending on how far down your engine is torn apart there are some things your might wanna consider before you start hopping it up. you have an untouched 20+ year old bottom end I'm assuming, if so it wouldnt hurt to replace all the bearings in your lower end. new bearings=less drag. Depending on what year that XR200 is you might be able to swap out the transmission and get a six speed. Again if the XR is the right year the tops ends are identical. you can use an XR cam for more top end or you can get a hold of www.webcamshafts.com for a new cam/valve springs/valves and maybe new rockers, not sure if they carry rockers for the 200X.

for head work i would open the intake port a little bit and leave it kinda rough, you want it to feel like a high grit sand paper, helps fuel/air mixture. exhaust port would be opend up a little the same as the intake except the exhaust port needs to be polished to a mirror finish. a polished exhaust port allow spent gasses to escape faster and will not allow the carbon deposites to build nearly as fast.

for the piston, if you want a solid trail bike i wouldnt go over a 10.5:1 piston. easy to start with nice power over stock but not peaky with no bottom end.
if you are building an MX bike go for the 12:1 and increase your intake valve to a 31mm from web cams and open your intake/exhaust ports a little bit more.

[Vealmonkey]

If you run the high comp. piston, you will have to run high octane racing fuel. If you don't run any higher than 10.5 you should be able to get away with pump gas.

[edog]

Use the search engine.You will find plenty on the 200X mods.

[tecate kid]

Talked to my buddy about his XR and its like a mid 90's model and he wants to get it running. Thanks guys, any of you guys have the powroll stroker kit installed? I am thinking about doing that to the 84 but want to make sure its going to give me a fairly large jump over stock (especially since its almost $750!) Anyone have those numbers? How about with a 10.5 piston, mid range cam, and maybe a 300ex carb?
tecate kid

[OldSchoolin86]

Use the search engine.You will find plenty on the 200X mods.

http://miltechsolutions.tripod.com/offroad/3ww/search.jpg

[tecate kid]

Hey 86 blow me! I have been and still have questions. I come here looking for the best way to spend my money, and make some power, not to be told how to use the site, I can take care of that myself. So once again get bent!
tecate kid

[OldSchoolin86]

Geez man, take a joke.:rolleyes:

[atcsteve]

Not to be rude,but with all the $ your gonna spend,why not get a 250r?They are fairly cheap to build,and the power gains are great.I ask this because Ive done a 200x and after it was all said and done,it wasnt that much faster.It still wasnt even close to my stock 81 250r.Anyways good luck in what ever trike you build!!

[smokinp]

wat year is your 200x?

[tecate kid]

The reason I am going to build this one is I have an 84 T-3 that is in good running order. I just want something for tooling around in the woods and local trails by my parents. I just figured as long as its apart I might as well try and get some extra HP. oldchoolin' sorry man I just got home from working a 13hr. day and my daughter was screamin', so I was a little testy. Sorry Oh and the 200x is a 1984, I have pics on the forum somewhere.
tecate kid