Help please

[4Q2]

I have 2 450r's one is mine son's and I just sold him my old yosh full system, mine had the hrc kit so I can't compare jetting, his is bone stock with the yosh so where should I jet his? I just bought a baldwin pipe for mine and it came with a 165 and a 185 main, should i use one of these in his or change the needle position or air screw, when I had the yosh on mine before the hrc it would backfire and shut down at 3/4 throttle.

[jeepnrocks]

is your kid going to run an open lid? for yours with the hrc lid i would start around a 185 and adjust from there. on my bike i switched to a 50 pilot and that helped the idle as well.

[4Q2]

He's running the stock lid for now, he's gotta save some $ for the hrc, plus dad always has to be faster.:D

[4Q2]

Mine had the same setup as his does now and it backfire in the upper rpms, after that I had the HRC installed and it took care of that, now that he has my pipe he's in the same shape I was, so what should I do to jet his ...bone stock with the lid but yosh full system, Thanks

[RedRacer44]

You should really run open lid, it'd make his quad run so much better :D

With the lid off, all you should need is a 185-195 and it should run fine. That seems to work for most everyone with a full exhaust and open air box. Its worked on all 3 TRX450Rs I have jetted, including mine.

I run a stock lid with a full HMF system and I have a 155 main jet.

[chad502ex]

I have a dyno plot with a difference of 2 rwhp with the only difference being the HRC airbox lid removed

In other words, remove the HRC lid and get 2 more hp to the rear wheels. I couldn't beleive the difference we saw!

:eek2: