Red hot pipes

Although we haven't talked about it in some time, yes, the right cylinder on these motors does run a little hotter than the left one, but it's not an issue usually, and not as bad on the '77 and older bikes. In '78, when the E.P.A. started mandating the carbs, it got worse. But still, that pipe glowing red isn't right, you're too lean. I'd step the pilots up some more.

I have a '78 and an '83, both of which would be more prone to doing this, and neither one does.
 
Although we haven't talked about it in some time, yes, the right cylinder on these motors does run a little hotter than the left one, but it's not an issue usually, and not as bad on the '77 and older bikes. In '78, when the E.P.A. started mandating the carbs, it got worse. But still, that pipe glowing red isn't right, you're too lean. I'd step the pilots up some more.

I have a '78 and an '83, both of which would be more prone to doing this, and neither one does.
i contually learn something from you 5twins. did know that the right cylinder runs hotter. By how much? do you know the reason?
 
sos!
i put new pipes from tc bros on my 78 and noticed this after a few mins of idle
along with the pipes i had bumped the #15 pilots in my vm 34s to a #17.5 (the next size up on jetsrus)

hopefully one side being hotter than the other is normal ? and these pipes are just thinner so its able to get red hot ?

would
apreciate some sound advice/observations on weather or not this is a big deal
Back in the 70's I purchased a set of Dunstall two into one into two exhaust system. Looked cool but in fact were rubbish. The pipes were as thin as the pipes under your sink, first time I fired up my XS2 the pipes glowed red for the first 10". Didn't change a thing other than the pipes and mufflers, which of course changed the way the bike breathed. The OE pipes have pipes inside of pipes to keep them from bluing.
Did you compare what you got to what you have?
 
Back in the 70's I purchased a set of Dunstall two into one into two exhaust system. Looked cool but in fact were rubbish. The pipes were as thin as the pipes under your sink, first time I fired up my XS2 the pipes glowed red for the first 10". Didn't change a thing other than the pipes and mufflers, which of course changed the way the bike breathed. The OE pipes have pipes inside of pipes to keep them from bluing.
Did you compare what you got to what you have?
Indeed, I've found it not so unusual for thin single skin header pipes to glow red. That above looks a bit excessive though, bright orange, that's very hot.
 
Retarded spark timing does it every time, even at idle.
Spark on exhaust stroke with cyl. full of fuel and exhaust valve open.
Lights off mix still in cyl. and down the pipe.
 
"noticed this after a few mins of idle"

At idle.........
Pilots, or carbs at that, will not supply enough fuel to get hot.
Engine will grow weaker as mixture is leaned out enough and run cooler.

Although, rich idle mix(normal) and an air leak at the flange that aspirates air into the exh. pipe will torch the pipe HOT, esp. with zero backpressure.

By the color, it looks like 1400° to 1500°F EGT. Normal idle is approx. 750-800°
 
and this wouuld be why my pipes are glowing ? also sorry not to ask redundant questions i just like to be clear
also i
Back in the 70's I purchased a set of Dunstall two into one into two exhaust system. Looked cool but in fact were rubbish. The pipes were as thin as the pipes under your sink, first time I fired up my XS2 the pipes glowed red for the first 10". Didn't change a thing other than the pipes and mufflers, which of course changed the way the bike breathed. The OE pipes have pipes inside of pipes to keep them from bluing.
Did you compare what you got to what you have?
yes the new pipes are very much thinner , im a welder fabricator by trade and it didnt suprise me when that right side glowed , but i decided to ask the forum anyways
 
Although we haven't talked about it in some time, yes, the right cylinder on these motors does run a little hotter than the left one, but it's not an issue usually, and not as bad on the '77 and older bikes. In '78, when the E.P.A. started mandating the carbs, it got worse. But still, that pipe glowing red isn't right, you're too lean. I'd step the pilots up some more.

I have a '78 and an '83, both of which would be more prone to doing this, and neither one does.
5twins with the knowledge we were seeking yet again 💪
 
Sorry many threads stepping on each other.

Answer is yes. Gross retard in spark timing will torch pipes.
Lean idle will not run that hot.

Running hotter when leaner is off-idle only.

You changed pilots and pipes and now runs hot on right pipe only?
 
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Sorry many threads stepping on each other.

Answer is yes. Gross retard in spark timing will torch pipes.
Lean idle will not run that hot.

You changed pilots and pipes and now runs hot on right pipe only?
its always ran a little warmer on the right side , my old pipes showed that in the coloration difference and like 5twins said i guess thats normalish for my '78

but now the pipe is glowing red after a change in pilot size (from15 to17.5) and new pipes that are considerably thinner
but to my observations the engine itself is not running any hotter , feels the same to the touch, i dont have a laser thermometer to confirm but i am very in tune with my bike i ride it everywhere and i dont feel a difference
 
its always ran a little warmer on the right side , my old pipes showed that in the coloration difference and like 5twins said i guess thats normalish for my '78

but now the pipe is glowing red after a change in pilot size (from15 to17.5) and new pipes that are considerably thinner
but to my observations the engine itself is not running any hotter , feels the same to the touch, i dont have a laser thermometer to confirm but i am very in tune with my bike i ride it everywhere and i dont feel a difference
Leaky flange is my bet.
 
i am with automan. Also, did you say you don;t have airfilters? just stacks? you should put the filters on. it is your daily rider
i know ive been meaning
to switch to filters but i had just fabbed a new electronics/battery box and the filters didnt look as good lol but i will do that
 
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