[Neiswonger6]

I have a 2013 trx 400x, about 2 months ago I was doing routine matainace and I noticed that I had a crack in my stock header, so I replaced it with a fmf powerbomb. I also have a lexx slip on. I went for a test ride and about 5 minutes into the ride my quad just shut off. I took it back broke it down double checked everything started it back up and it shut off. I got my infrared gun out because my father in law said my new header was glowing, when he tried it, and the pipe was stupid hot, about 240 to 270 just insane. I went to the local shop and got some new jets it's what they recommended, put the jet in and still nothing. I've been gone for over a month and I really want to get back and ride but I still dont know what the problem is anyone have any suggestions or help?

 

[SlammedRanger]

240-270 on the header wouldnt be what i consider insane? Depends where you temped it but right up close to the head i usually see 500+ after idling for 5 or 10 minutes. What size jets did they give you? I would be guestimating 175-180 main jet if you removed or modified the airbox lid and a 42 pilot jet for sure reguardless. The 42 pilot jet can even be put on a stock 400. The 38 pilot they come with is so lean to meet emissions regulations.

 

[Neiswonger6]

I thought that was hot but I never really checked and I checked it right next to the cylinder and I think my jets are 175 and 42 I believe but they also told me to try a 190 and that didn't do a while lot, somebody told me it could also be the valves but I'm not too sure. I've been around machines almost my whole life but I never ran into any of this

 

[SlammedRanger]

When it shuts off does it still crank over or does it lock up? Any smoke out exhaust? Aftermarket headers can glow expecially at idle being this engine is air cooled without air flow it dosnt have anything to keep it cool. Your temps on the header i would consider normal. So its not the heat causing the shut down issue most likely.

 

[Neiswonger6]

It only shut off once and it cranked afterwards and than I replaced the jet and it hasn't shut off since, and I have been kind of leary of taking it out because I dont want to ruin the motor.

 

[SlammedRanger]

Well you can rest easy because this motor is dang near impossible to blow up completely. I have first hand seen one run with zero oil in it all day and just need rings and a hone. If it cranked right back up then you probably just had something in the carb that clogged a jet and shut it down or an electrical issue somewhere that killed spark for a split second. I would only be worried if my leg was cooking or it shut off and wouldnt crank over anymore. My .02

 

[Neiswonger6]

Already thank you for the info your the only one that has really helped me out all the parts stores just blow smoke where I'm from

 

[SlammedRanger]

No problem! Always glad to help!