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Header gets super hot

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Pipe turns cherry red and burns holes in everything.. turns red extremely quick IMG_0224.JPG

How can I fix this

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How bout some more info? Stock, mod, race gas?  This is normal if you let your machine sit and idle for a period of time in which your not suppose to do. 

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This is normal on many 4 strokes.  idling for any extended period of time can make them red, especially if it's an engine meant for high RPM riding. So, maintaining higher rpm will help, as it brings more fuel to the engine, keeping it cooler (oxygen burns much hotter than gasoline. There's a higher oxygen to gas ratio at idle). But personally, I would jet up to help reduce the heat. Just because it's normal for the header to turn red doesn't mean you shouldnt take every measure possible to keep the heat as low as possible. Your valves will burn up.

Also keep in mind that low rpm riding is the worst culprit as far as general engine over heating goes. The higher the rpm, the faster the coolant circulates.

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seems like a little tooo hot , tooo fast ,,, ???? have you checked your cam timing ????? , in the olden days 4stroke.racers would advance the cam to increase motor useable RPMs , if the cam is running too advanced it will open the exhaust valves way too early and thus ALL that exploding fuel will happen in the header portion of the pipe , instead of in the combustion chamber on top of the piston where it is supposed to happen , 

you will also burn exhaust valves quickly and with these multi-valve type motors that can add $$$ up quickly 

just a possible CYA     =  latorgatorz DDD

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4 hours ago, Nickb said:

This is normal on many 4 strokes.  idling for any extended period of time can make them red, especially if it's an engine meant for high RPM riding. So, maintaining higher rpm will help, as it brings more fuel to the engine, keeping it cooler (oxygen burns much hotter than gasoline. There's a higher oxygen to gas ratio at idle). But personally, I would jet up to help reduce the heat. Just because it's normal for the header to turn red doesn't mean you shouldnt take every measure possible to keep the heat as low as possible. Your valves will burn up.

Also keep in mind that low rpm riding is the worst culprit as far as general engine over heating goes. The higher the rpm, the faster the coolant circulates.

I agree with the comment on higher RPM, but airflow is equally important.  Circulating coolant can't cool as well if there is no airflow over the radiator.  Also, airflow over the engine as a whole (as in moving the bike forward) will help cool down that hot header... direct airflow cooling.  Good luck.

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What's the jetting?  Maybe it should be richened.

Is there an exhaust leak anywhere?

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It’s “normal” but also more prevalent if you’re jetting is on the lean side.

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This is very likely a sticking hot start valve that is not shutting.  This is common on CRF150R/RB models.  Check this first. 

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Sticking or not sealing exhaust valve or retarded ignition timing can cause this.  That's a very bright glow for being a daylight picture. Lean would backfire LOUDLY.

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I had a dr350 with a defective black box that caused the ignition timing to be retarded. a lot of the combustion was going on after the exhaust valves opened.  pipe got red if it was idling or riding.  a replacement black box and it was fine. one thing to check.

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If anyone noticed this is a quad, not a bike. The owner should have that hot pipe land on his face.

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Everyone is saying go richer on the jetting but I think the opposite because if it's too rich then the mixture is still burning when the exhaust valve opens.

Either way, just go by the plug color. If it is black then make it leaner.

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I say shut it of it will stop glowing right away.  

Many fuel injected bikes do that if you leaf them running with a high Idle after start up.

Yz and wr are bad for it as well

They do run lean on idle and 0 airflow while siting still . High Idle makes it worse.

As soon as the engine makes power it goes away. At high power there is enough exhaust flow to move the heat out.

 If you are sure about valve lash and all your maintenance is up to speed and the bike runs perfect ride it.

If it does not run perfect or you have not looked at the vales or anything else for some time maybe do some maintenance to make sure all is well.

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10 hours ago, DGXR said:

I agree with the comment on higher RPM, but airflow is equally important.  Circulating coolant can't cool as well if there is no airflow over the radiator.  Also, airflow over the engine as a whole (as in moving the bike forward) will help cool down that hot header... direct airflow cooling.  Good luck.

Of coarse air flow is important, one of the most important things for any engine to run well. But you never want too run anything too lean. Thats the worst thing. They run lean at idle. I have a few 2 strokes, and to ride in the winter they MUST be jetted up or they will blow up very quickly...this is simply because the cold air has more oxygen in the winter. Although 2 strokes are more sensitive and tempermental to this stuff. Fairly recently I had the same problem with my 4 stroke (LTZ400), header glowing when idleing. I jetted up the pilot a couple sizes, problem solved.

The comment about coolant flowing pertained to general engine overheating. Not specific to the header

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7 hours ago, hondaxr650rrrr said:

If anyone noticed this is a quad, not a bike. The owner should have that hot pipe land on his face.

Doesn't make any difference...the number of wheels is not a factor here lol

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Posted (edited)

So realistically, there's any number of possibilities that could be causing this problem. Especially with todays complex 4 strokes. But, More than likely, jetting up will help tremendously, if not completely solve the problem. But when it comes to diagnostics, do yourself a favor and rule out the simple stuff first. Your local shop will have jets for like 3 bucks a piece. If fuel injected, do whatever needs to be done to increase fuel ( i dont own anything fuel injected, so i dont know much about it). If jetting doesn't help then go onto the next thing.  Don't jump to valve issues or faulty CDI boxes until you have to.

Edited by Nickb
Please, please do not listen to anyone who says go leaner.

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8 hours ago, hondaxr650rrrr said:

If anyone noticed this is a quad, not a bike. The owner should have that hot pipe land on his face.

Why would he want a hot pipe land on his face ?

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19 hours ago, BikerBoyL said:

 

Pipe turns cherry red and burns holes in everything.. turns red extremely quick IMG_0224.JPG

How can I fix this

 

check your exhaust valves if they are not completely closed when it fires the explosion goes straight out the exhaust i had this happen on a road bike years ago and burnt all the chrome on one exhaust

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