Running hot

[Caseys 300ex]

Well i have a 1998 300ex with a cobra pipe, a k&n filter, and no airbox lid. Well today i started it up and i punched the throttle about 2 times then i turned it off. Well i touched my exhaust and it was burning hott. What should i do to cool it down? Whats the problem here?

[Mx_523]

If you touched the header its going to get real hot. Make sure your oil filter isn't installed backwards. That can overheat your machine because lack of oil getting to the components.

[Caseys 300ex]

Ill look at that. Thanx Mx_523

[Architects]

Seems normal to me. It is after all expelling exhaust gas which is hot.

[CannondaleRider]

Wow, you must have a seriously devastating, unavoidable motor issue, if your exhaust is hot.:D

Seriously, if it is like WAY WAY hotter then normal, its possible you have a problem.

Have you made sure your jetting is right?

[Caseys 300ex]

I know its normal for an engine to get hot. But it only fan for a second and it got really hot. I wouldnt think that is normal.

[GPracer2500]

Did you rejet after your intake and exhaust mods? If not, you're probably lean and leaness can create excessive heat. However, feeling an exhaust with your hand and trying to make a judgement about how hot it's getting is not a good way to evaluate your jetting.

[rooster300ex]

I can run my motor for a second or 2 revving it up and when i shut it off the header is hot. Its normal. But if you didn't rejet its gonna create more heat.

[Caseys 300ex]

ya i havent gotten around to rejeting yet. So ill make sure ill go that. What do u think i should run as far as jetting?

[CannondaleRider]

:eek: .....how long have you ran it since the mods, without rejetting it?

You can do some serious damage if you run it in to lean of conditions.

Also, we can't just tell you what your jetting needs to me. Depends on actual exhaust flow, atmospheric pressure, elevation, etc. etc.

You'll need to do plug runs(i'd richen it up first), read the plug, and adjust accordingly

[rooster300ex]

Originally posted by Caseys 300ex
ya i havent gotten around to rejeting yet. So ill make sure ill go that. What do u think i should run as far as jetting?

Try turning the fuel screw out about 1/2 turn,then get the needle out of the slide and put the e-clip down 1 notch to richen it up, and then bump up your main jet size up 1 or 2. Just see what works best. i'm gonna give you a link to dynojets website so you can see how everything is done. Its just to show you where everything is on you carb. It shows you how to get to the needle, it shows you where the fuel mixture screw is, and to get to the main jet just look on the bottom of the carb. all you gotta do is take that lil cap off. Oh yea stock fuel mixture screw is 2 1/4 turns out. incase you wanna bottom the fuel screw and just turn 2 3/4 out. that would be about a half turn. You'll figure it out.

[Caseys 300ex]

haha Well its only been like this for a day. I just wanted to put a pipe on cuz i was bored. But i think ill try a 132 main.