approx. how much HP bored and ported 200x

[oldred95]

Finally got the right piston for my '84 200x. Its gonna be a real simple build. .040 over flat top WSM piston, mild port work, basically clean up casting flash and valve seat to head area, Bassani exhaust, K&N filter and the proper jetting. I read stock HP was 12-14 which isn't bad considering how small the engine is. Would my mods be worth maybe 2-4 HP, somewhere in there? Any more torque? I've never ridden a 200x so not sure what to expect. Ridden many a 200s's before. How would it compare to a 200s? TIA

[Rex Karz]

The 200x will make you wonder why you rode the "S" for so long.

[Dammit!]

I won't bother guessing at HP numbers but those mods will help wake it up a bit for sure. One thing most people neglect though is the gearing. The stock 200x gearing is pathetically low. Especially when you consider very few people still run 22 inch rear tires on them. The extra power won't do you a ton of good with that low gearing. If you're running 20 inch tires try 13/38 gearing (maybe even 14/38). With 18's try 14/36. Night and day difference imo.

The mods on my old 200x were 10.25:1 piston, megacycle racing cam (high end model), heavy duty valve springs (a MUST with a performance cam!)supertrapp pipe with 18 disks, K&N air filter and... something else that I'm forgetting. I ran 14/37 gearing with 18 inch tires and that little 200x was pretty damn quick for what it was. My current 200x project will probably have a little more done to it than that one did.

[oldred95]

Its got the original style tires on it and they are in good condition and thats probably all I'll ever run on it, except for my 21 inch paddles from time to time. You're saying it needs to be geared higher? Higher gearing means less power. I don't need it to go 70 mph. 50-60 is plenty for me. I doubt it even gets ridden much outside of the sand dunes and the river when it gets low during the summer.

[SYKO]

part of the power equation is having a better set of tires that are able to put the power down better I.E better traction, you may only want to go 55-60 mph, but with older tires you may be doing more spinning, go to a more agressive 20 inch tire holshot/shredder/fast tracker and that will wake up your sens's of what you were missing. you can actually gain speed with better tires. put it this way my 83 300 has wicked traction with 20 inch tires, it sucks with 18 inch tires and I want to die, my 85 sucked with 20 inch tires but it rocked out with 18 inch tires I have an 85 200x (stock) it had the 22 inch tall factory tires on it, one day I put my 20 inch shredders on it, and it was like a completly differnt machine!! it went faster, handled better, and was more plain fun! try it dude!

[xman23]

you you deff have to change the gearing, it plain out sucks stock, way to low, If you dont car bout top end I would still go up 1 tooth in front or go down 2 in back, right now i got my 18s on and im rinning 13/35 and its really good cept when i het deep snow, for mods i have a 10.25 high comp piston, heavy duty clutch springs, supertrapp pipe, webb cam

[oldred95]

Like I said I've never ridden a 200x so I really won't know how it feels on gearing until I get it back together and go ride it. My 125 is bored .040 over and I dropped the rear sprocket down three teeth and it worked a lot better all around. I could run in 3rd where with stock gearing 2nd was always too low and 4th was too high. Still got another month or so before the 200x gets put back together. I need to get a smaller grinding stone so I can clean up the casting flaws around the valve guides and clean up around the valve seat to head area and then get it taken down to the machine shop for a bore and valve seats ground for new valves.


What about my clutch? No idea on the condition of it and its stock probably original as far as I know. It will probably be next.