another jetting question w/Sparks x-6

[bmurray]

First of all I have searched for this and haven't found a clear answer. I just installed a Sparks X-6 (with quiet core, if you want to call it that), Twin Air filter and modified airbox lid. It was suggested to run either a 170 or 165 main. I put in the 165 and seems to rev ok, but bit of a flame if you nail the throttle and left off. What is the best way to determine which jet would be right? Thanks

[tar]

I just put mine on today and I have
Curtis Sparks x-6
K&N air filter w/ lid off

I am running a 160mj and it is perfect.

[tar]

Try running a 155 or 160

[bmurray]

on the sparks web site it suggest a 155, but I will try a 160. what's the best test for selecting a main jet?

[krt400ex]

It semms to run alright? Does that mean you think it could run better? If the bike backfires, pops, gets too hot too fast, or fells like it is starving for fuel then your too lean. Does it cough down low or smoke a little when you shift gears or chop the throttle? Then that means you're running rich. Did you change your pilot jet? That may be why it's running poorly off the bottom. Also, I was wondering how the X-6 works because I can get one cheap. I was told that it gives you more top end. Does it give you more bottom end too? Do you lose any bottom end. I like more off the bottom, but if I can get top too then I'll go for it. I just don't want to lose any bottom end. Oh ya, does that quiet core quiet it down at all or is it loud as ever.

[tar]

I love mine if you can get one get it. I have no regret about getting mine. It sounds great you can feel the power it puts out and it looks great.

[bmurray]

My 42 pilot will not be in until Thursday. I had a 165 and now a 170 main and it doesn't blow any smoke out. I'm going to play with it a bit and see what I come up with. I will pic up a 160 also. I may need adjust the fuel/air to 2.5 turns from in and drop the clip on the needle. I just don't want to run it lean! Boy does it feel mean with this Sparks X-6!