starting / running problem

[TRX450R_Racer]

The main jet and the pilot jet that are inside the bowl need to be tight. If you loosened them take it back a part. While the bowl is off make take out both jets and make sure all of the holes are clean. then put them back in and tighten them back down. The only thing that shouldn't be all the way tight is the air/fuel mixture screw and it is outside the bowl. eveything inside the bowl needs to be tight. Whoever told you to loosen them, stop taking their advice.

[flt mech]

I did that earlier today (tighten up the jets).  It still runs like S*&T.  I'm about 2 secs away from running to a shop.  The thing that realy makes me mad is now' I'm going to pay like $100-$300 to find out it was something stupid that I overlooked.     

[VForce700]

here is an idea. take the mixture screw and screw it in until it stops. do not over tighten. then unsrew it 2-1/2 turns out. that should give you a good starting point to see if it's a air/fuel problem. If that does not correct it I would see if there is something like a pick up coil that can be replaced. I am not familiar with the TTR series, but it sound like some familiar issues I have dealt with before.

[Chevy1500z71]

here is an idea. take the mixture screw and screw it in until it stops. do not over tighten. then unsrew it 2-1/2 turns out. that should give you a good starting point to see if it's a air/fuel problem. If that does not correct it I would see if there is something like a pick up coil that can be replaced. I am not familiar with the TTR series, but it sound like some familiar issues I have dealt with before.

good call, you need to get a feel for tuning that tho, not hard at all but for someone who loosened up his main jet it may be above your head lol, im jk. you need to play with the air fuel, it can make a diference.