woodsbikemike Posted September 20, 2005 Just got the girlfriend a 04 XT225, its a good starter bike for her but it runs like crap at 11,000 feet. Any ideas for how to jet it for high altitude? It will be ridden from 5,000-14,000 feet. I know there is not a single jet to cover all of this perfectly, but what would be a good compromise? Share this post Link to post Share on other sites
kmurray Posted September 27, 2005 Hi, I'm not an expert, but this is what I did. I replaced the float bowl screws with Allen head screws, and I bought a handful of jets (Mikuni large round). Then I dragged the bike to the top of the mountain where we ride (about 9000ft), and I swapped jets until it ran decent. What did I end up with? Just one size down - 127.5. With the stock jetting the bike was unridable at any altitude over about 7000ft, it would buck and cut out and turn plugs black. Now it runs fat at about 9000ft and 80F (burbles a little) but it's ridable. I don't want run it leaner because we do go riding closer to home (2500ft) in winter (70F). I kind of don't believe that just one jet size made that big a difference, but that's what happened. I dismantled and cleaned the carb twice, I checked the float level carefully, but the main jet did the trick. What's weird is that a friends XT runs fine without any changes. Hope this helps, Kenneth Share this post Link to post Share on other sites
ODH446 Posted September 27, 2005 Usually at higher altitudes the air is a bit thinner so you have to lean the carb a bit for the bike to run right. kmurray is right, trial and error. But you will have to go to smaller mj for it to run correct. Share this post Link to post Share on other sites
russell3 My Ride Posted February 27, 2009 I know this thread is way old, but I found it searching for some answers. I was wondering if anyone has ever had to change pilot/needle clip position/needles/cutaways for this bike. I have a 93 xt225 and I am borrowing it from my mom because my other bike(cr500) got stolen. I live in utah and my mom in washington, so the elevation is drastically different. I ride from 4500 to about 9000 feet. It runs awesome at sea level, but when I ride here, it's a gutless wonder because it is so stinking rich. I think I have a 120 main in it. I need it smaller. probably a 115 or 110 but I am not sure yet. Share this post Link to post Share on other sites
harrylsingleton Posted June 17, 2015 I have 2 XT225's, 1994 and one and 96 and have Janet both of them main jet at 1:20. Share this post Link to post Share on other sites
harrylsingleton Posted June 17, 2015 Please cancel previous accidentally sent texts about 2 XT225. Share this post Link to post Share on other sites
harrylsingleton Posted June 17, 2015 I have 2 XT225 bikes, one a 04 and one a 96. Both run well at 8 to 12,000 feet in Colorado. Having an awful time. Both main Jets are 120. Maybe will have to quit voice texting. Share this post Link to post Share on other sites