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Honda FMX 650 Red Hot Exhaust

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Hello all! It is my first post in the Forum..

I am a new owner of a used FMX 650, and i see the exhausts getting red hot!

This is how it looks after 2 minutes of idling with the choke on..

Is it NORMAL?

Thank you in advance..

Edited by NuMcA

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THX Scalejockey..

Unfortunately, upon dissembling the bike, i saw many problems (like cracked valve cover).

Now i am afraid it might have been seriously tampered..

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Shouldn't the choke be switched off once the bike will maintain an idle?... two minutes seems way too long.

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You may have a cdi problem, an engine with the timing running too far retarded will do that. May just be jetting but I doubt it.

The other thing it could be and most likely is the cam to crank timing is off a tooth maybe two, check cam chain timing. Running it like that is going to ruin the exhaust valves

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Hello all! It is my first post in the Forum..

I am a new owner of a used FMX 650, and i see the exhausts getting red hot!

This is how it looks after 2 minutes of idling with the choke on..

Is it NORMAL?

Thank you in advance..

That's normal with the bike sitting still with no AIR FLOW across the head surface, jetting it richer will help a bit but with no air flow sitting for two minutes it's going to get hot.

Put a fan in front of the motor and if it still glows red than you have a very lean running motor.

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I agree with CW...........no air flow,probably lean jetting.........coupled with a thin walled exhaust header on an air cooled engine with the revs up sitting still= red hot exhaust........

I also agree that this tends to be a "not good" situation for the exhaust valves in most engines..but......i`ve seen this repeatedly in these engines with no damage to the engine or valves..

Check your jetting,,,and get the engine off choke as soon as you can..

B

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Running it for that long on choke is bad if it wont idle off choke check your pilot jet make sure its clear and red hot exhaust is a rich issue not lean the choke was on wich makes it run rich loading the exhaust with fuel that is still burning making it hot trust me on this one

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A rich condition will spill unburnt fuel past the exhaust valve and make your pipes burn red, also letting your bike sit and idle for two or three minutes with no air flow will contribute to this phenomenon also.

If the bike will not run without the choke you have a lean condition, plugged slow jet or an air leak which will make your motor run hot and turn your pipes into a glowing blob of molten metal along with your exhaust valves.:lol:

Glowing pipes is normal on an air cooled bike with no air flow, because it "extremly" raises the cylinder head temps, if you were to put a fan in front of the motor I doubt they would glow red.

You should never let a big single sit and idle for long periods of time without a fan in front of it..jetting it richer does help.. but than we have ignition timing and cam timing to take into account here also.

Retarded ignition timing contributes to this along with long duration camshafts...holding the valves open longer lets some unspent fuel out the exhaust and so does retarded timing at idle. Most big singles have retarded ignition timing at idle so the motor doesn't kick back on startup and then the curve changes after idle.

So you have an air leak or a lean pilot jet making it not want to run off choke.

I would check for an air leak first like loose carb or a vacuum line may have came of and then pull the carb and clean it and go one size larger on the slow jet.

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Thank you for the responses guys!

I not looking to solve this problem any more, because upon disassembling the bike, i saw the carter cracked, the valve cover broken, and the tail part of the frame was bend..

I am taking legal action against the seller who was advertising it as "unscratched" and "mint used condition"..

Thank you all again..

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Thank you for the responses guys!

I not looking to solve this problem any more, because upon disassembling the bike, i saw the carter cracked, the valve cover broken, and the tail part of the frame was bend..

I am taking legal action against the seller who was advertising it as "unscratched" and "mint used condition"..

Thank you all again..

Well........that sucks....

P.S. What is a carter????????????????

B

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Well........that sucks....

P.S. What is a carter????????????????

B

ya got me maybe the head was cracked???????? I dunno

The darn thing was pretty hot to glow all the way to the back of the pipes like that.

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ya got me maybe the head was cracked???????? I dunno

The darn thing was pretty hot to glow all the way to the back of the pipes like that.

Yeah,i mean you see them glow,but re-looking at that video is kinda scary...usually a little cherry for a few inches.........but a foot is downright scary...on the upside though...a could light my cigar off it,,and would act like a nightlight when i stop on nightrides:thumbsup:

That`s if i ever see my engine again...some guy is rebuilding parts of it,,,and i think he drinks alot:busted:

:lol::smirk::)

B

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Thank you for the responses guys!

I not looking to solve this problem any more, because upon disassembling the bike, i saw the carter cracked, the valve cover broken, and the tail part of the frame was bend..

I am taking legal action against the seller who was advertising it as "unscratched" and "mint used condition"..

Thank you all again..

Never never never trust what a stranger says,they might think that is really nice to them or simply dis-honest scum.

:lol:

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P.S. What is a carter????????????????

That's the sump, the engine casing around and under tha crankshaft. It is Greek tech lingo, so you may forget the term now and never come across it again.

By the way, NuMcA, I'd be very curious to see where your legal steps lead you - as in VERY curious, especially nowdays...

Anyway, ΚΑΛΗ ΤΥΧΗ, and keep us posted of developments

M.

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Thank you for the responses guys!

I not looking to solve this problem any more, because upon disassembling the bike, i saw the carter cracked, the valve cover broken, and the tail part of the frame was bend..

I am taking legal action against the seller who was advertising it as "unscratched" and "mint used condition"..

Thank you all again..

Honda FMX was my previous bike... I'm thinking how could it be possible to do such serious damages to an indestructible engine like it is...

Anyway it's not the first time that I see red hot exhaust due to air excess in the mixture. Take particular care of it because high temperatures in the combustion chamber lead to early engine wearing and failure.

But it's not the first problem now, isn't it? I'm sorry for your mistake...

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Guys, thank you for your answers.

Today i finished my took my first legal action. I have send him an Nonjudicial Notice of Default (Εξώδικο) and i am waiting for the ultimatum's time to expire. If not responded, i will fail against him for fraud. After a lot of invastigation (which i should have done earlier) i found that the motorcycle has had a registered accident with the insurance company..

Will keep you posted..

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