Flatlander78
New member
I was wondering if anybody has had bad results with yamaha's jetting recomendations listed in the factory service manuals. In your experience, are they typically on the rich side, lean side, or right on. I talking on a completely stock engine obviously. The reason I ask, is I bought a 01 Mountain Max 700 and was told it had the factory jetting. I have ridden about 350 miles around my home area (2200 ft elevation) and it didn't seem to run to bad. Plugs looked good. We'll I took the carbs off to clean them and rejet to my elevation here since we are a little higher then what the factory jetting is and I am also installing an ATACC. What I found was 132.5 main jets (8000-10000 elevation according to yamaha), #55 PJ, needles on #2, and the air screw two turns out. According to that I should have been really lean with that jetting at my altitude. Wouldn't this be noticable on the plugs or shouldn't I notice something in the engine? I don't really know what to make of this. I can't believe I didn't melt a piston. Any thoughts??? What are you MM owners running?
TJ500
Member
I had to rewrite this post because I hadn't noticed you were from Montana... Your temps are not nearly as cold as we see in Manitoba...
I follow Yamaha jetting charts for my 02 MM700 and never had a problem... Just be sure to jet for the coldest temps and lowest elevation you'll be riding at... The Attack instructions will tell you the same and then take care of the rest...
I follow Yamaha jetting charts for my 02 MM700 and never had a problem... Just be sure to jet for the coldest temps and lowest elevation you'll be riding at... The Attack instructions will tell you the same and then take care of the rest...