Originally Posted by CDG
I bought an XT 225 for my girlfriend about 3 months with only 7000K's on the clock here's a pic,
I have just taken the tiny snorkel out of the air box to get it breathing a bit better and it seems to be surging just a little in the higher rev range.
It seems to have heaps more pull with this mod but not so good up high, also its ok up high if you are steady on the throttle but just when you give it some.
I've been on xt225.com but havent posted there and I olny just found this thread so I thought i'd try here first.
I plan on doing that exhaust mod but thought I'd sort this out first and see how it goes once properly tuned.
Whats your elevation?
If you are at sea level in a low humidity enviroment then these are the mild jetting and exhaust mods that worked very well for me....
Exhaust and Airbox:
Remove snorkel though if you get hit with high wind just right the drastic pressure change in the airbox will cause the surging that you mentioned. Drill the entire baffle out of the exhaust. Use an aftermarket air filter (not K&N)
Use a 42.5 pilot jet (the bike will fire right up and run smoothly very quickly) and a 130 main jet. Shim the needle with one very thin washer.
Thats it. If the enviromental conditions are right then these changes will make you very very happy with the bike. Drastic improvement from stock. If you are above 2000 feet or live in a high humidity enviroment then you'll have to adjust your jetting accordingly but I can't help too much there.
With those changes the bike is still getting on average of 80 miles per gallon. Can't complain.
And make sure your float valve is not gummed up from old gas. That caused me alot of grief. Put a new one in and all is great.