[img]i/expressions/face-icon-small-confused.gif[/img]I have a TRX 450r and just bought a HMF full exhaust eliptical series and ordered a FMF jet kit because it was the only one they had. I had some assistance from a friend rejetting the carb but when completed and gave it a test run it ran like crap. It ran better with the choke on but not quite the best either

 

what size was your factory jets? and what size did you put in? i had to rejet my banshee like four times when i put on aftermarket pipes. and air filter.

 

What year 450R. I would forgot the jet kit and just go to your dealer and get the OEM jets at the part counter and save yourself $50. If it's an 06 then start with a 160 or 170 main jet. Is the air box lid off? That will make a big difference. Pop off the lid and add a 170 main and bump up the pilot jet one or 2 sizes. If you dont like running without a lid then get a Outwears lid cover. It will keep the filter clean and you want have to clean it so often.

 

Jetting is trial and error. Ive found this article on jetting really helpful, and it describes the symptoms of lean and rich, to help decide which way to go on jetting. But Id would this its too lean right now, because you said it runs better with the choke on. Dont be afraid to experiment, and try different jets...thats how we all learned.
http://www.motorcyclecruiser.c...carburetion/index.html