I have a 1987 yamaha big bear, and i have now put a custom intake and custom exhaust on it and I know it needs a jet kit but I just need to replace the main jet. I have a 120 main jet in it now what size should I go up too and where can I just buy jets at ????

 

Rule of thumb is 10 to 15 % increase depending on altitude,temp,etc with improved intake and exhaust flow. Plug chop it first and see how it does with stock jet. Plenty of places online,along with Ebay and local dealers that usually have plenty of jets. YAMAHA BIG BEAR YFM350F YFM350FW main pilot slow jets kit

 

Thank you cause I have found whole jet kits that cost upwards of $40, ill use that site and hopefully be riding in the mud holes this weekend

Thanks again

 

Rob its still gone be slow!!