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Hi Jon:

I have a TXT200 in which I use a 100:1 ratio (Yamalube 2 in racing gas) for trials riding. I plan to also use the bike for general trail riding where my average speed will be higher and the motor will run for a longer continuous time than during a trials event. Should I richen the oil for trail riding?

Thanks for any information,

Mike O'Donnell


You might want to go to maybe, 75:1 for tougher trail use with higher sustained speeds. I run my bigbore G-G at 80:1 but only because it makes ME feel better and not that it really needs it. You may want to run a plug check under those conditions just to be sure. The weather is turning colder (denser air) so jetting that was spot-on this Summer will be too lean and may cause problems under the conditions you describe. Look for the plug to be a milk chocolate brown color and always error on the side of being too rich. On long downhills (if you have them) blip the throttle now and then to add some fresh premix to the engine during engine braking.


Professional tuner and 'Trials Competition' writer Jon Stoodley has very kindly stepped up to the plate to answer your questions. If you're having problems, or need some advice just send an email to Jon. If it's something that could be useful to others, we'll post it on the site.
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