what temp should the exhaust pipes be?

[mrbsyammy]

Ok I have a very clean XS1100 special with 20,000 original miles on it the head gasket was leaking so I replaced it and since I had it apart I relapped the valves and put the correct shims in and since then it hasn't quit ran right. Its been stumbling on idol and stumbling at 3,000 rpm besides for that it runs out very strong. I put my temp gauge on the after market 4 into 1 headers and the pipes were hitting mid 650 degrees which I thought was a bit lean so I pull the tops of carbs which was a dirty rotten SOB since the Phillips screw were beyond tight had the use hammer and chisel on 3 of them and of course the worse ones were the ones you couldn't get at straight because of the frame and as long as I was at it I 86ed the octy that%$#@*&%& thing what dumb ass came up with that nightmare should be shot! And I replaced all the Phillips with S/S Allen head bolts so I would never have that problem again. Anyway I put one washer on the needle to raise it and it seem to start and idol a little better with choke one but the rest didn't change much still stumbles at 3,000 rpms and it still doesn't idol that great? Temp on it now is upper 500 degrees so whats next? new plugs filters like new oil n filter new so whats next? ran great before I took it apart and still balls out runs great it just at 3,000 rpm n idol? still too lean? And no the idol circuit isn't dirty.
Till then Mr.Bill

[bikerphil]

The timing may be off when you took the cams out, make sure the marks line up on the cams/caps when at TDC, retarded timing will raise the exhaust temperature. JAT

[IanDMacDonald]

Howdy Mr. Bill. Got some restaurant background (86ed)? Anyways, I'd be more concerned with plug color over header temp.

[mrbsyammy]

Howdy Mr. Bill. Got some restaurant background (86ed)? Anyways, I'd be more concerned with plug color over header temp.

86ed CB talk

[mrbsyammy]

The timing may be off when you took the cams out, make sure the marks line up on the cams/caps when at TDC, retarded timing will raise the exhaust temperature. JAT

Right on the money but thanks for the thought..
Till then

[WMarshy]

Lean f/a mixture burns hotter than a rich mixture. You sure your not bloody rich? Were all 4 pipes the same temperature or was just one or two down in the 650 range? Some better details could help us help you but in general, exhaust temperatures are not really used to help tune. Usually only use them to determine if one cylinder is not firing. I'd expect the exhaust to be 800 or more I it's firing. Do a little search and you could probably find a few posts from use reporting their temps and asking they same questions you are...

[mrbsyammy]

Lean f/a mixture burns hotter than a rich mixture. You sure your not bloody rich? Were all 4 pipes the same temperature or was just one or two down in the 650 range? Some better details could help us help you but in general, exhaust temperatures are not really used to help tune. Usually only use them to determine if one cylinder is not firing. I'd expect the exhaust to be 800 or more I it's firing. Do a little search and you could probably find a few posts from use reporting their temps and asking they same questions you are...

Hum? I've been taught just the reverse rich is cold and lean is hot! give that a little thought? too much fuel will cool the combustion chamber and not enough will make it hotter. I am 66 yo and have built several race engines and have raced semi pro and that what I have learned/ too lean and your plug will be white, the richer your mixture the darker your plug. Lean is hot rich is cold? A lean engine will burn holes in your pistons and burn your valves fact I've done my share of burnt valves and pistons.
Thanks for your thoughts.
Till then Mr.Bill

[WMarshy]

Hum? I've been taught just the reverse rich is cold and lean is hot! give that a little thought? too much fuel will cool the combustion chamber and not enough will make it hotter. I am 66 yo and have built several race engines and have raced semi pro and that what I have learned/ too lean and your plug will be white, the richer your mixture the darker your plug. Lean is hot rich is cold? A lean engine will burn holes in your pistons and burn your valves fact I've done my share of burnt valves and pistons.
Thanks for your thoughts.
Till then Mr.Bill

We are saying the same thing about f/a ratio and heat generated as a condition. What your not picking up is that I think 600 deg header pipe is relatively cold. Combustion temperatures are closer to 4 digits, therefore 600 seems low, which is why Im askin if you could be overly rich.

Exhaust temperatures could be used to help tune and engine but not without EGT probes. Shooting a pyrometer at the down tube has a lot of variables involved and is not a common practice for the average person.

[mrbsyammy]

Hum? I've been taught just the reverse rich is cold and lean is hot! give that a little thought? too much fuel will cool the combustion chamber and not enough will make it hotter. I am 66 yo and have built several race engines and have raced semi pro and that what I have learned/ too lean and your plug will be white, the richer your mixture the darker your plug. Lean is hot rich is cold? A lean engine will burn holes in your pistons and burn your valves fact I've done my share of burnt valves and pistons.
Thanks for your thoughts.
Till then Mr.Bill

Ignore this reply tried to delete it and too late

[mrbsyammy]

Lean f/a mixture burns hotter than a rich mixture. You sure your not bloody rich? Were all 4 pipes the same temperature or was just one or two down in the 650 range? Some better details could help us help you but in general, exhaust temperatures are not really used to help tune. Usually only use them to determine if one cylinder is not firing. I'd expect the exhaust to be 800 or more I it's firing. Do a little search and you could probably find a few posts from use reporting their temps and asking they same questions you are...

Just for shets and giggles are lean it out and see what happens that's one way to find out I guess?
Till then Mr.Bill

[WMarshy]

This might help...

http://www.xs11.com/forum/showthread...st+temperature

Im unsure what temperature the headers should be on a well tuned motor. No one seems to have reported it... then, back to the variables thing...

[WMarshy]

Just for shets and giggles are lean it out and see what happens that's one way to find out I guess?
Till then Mr.Bill

Just stick with plug reading, way cheaper then turning your solid pistons into ventilated pistons.

[mrbsyammy]

We are saying the same thing about f/a ratio and heat generated as a condition. What your not picking up is that I think 600 deg header pipe is relatively cold. Combustion temperatures are closer to 4 digits, therefore 600 seems low, which is why Im askin if you could be overly rich.

Exhaust temperatures could be used to help tune and engine but not without EGT probes. Shooting a pyrometer at the down tube has a lot of variables involved and is not a common practice for the average person.

I apologize for my reply I tried deleting it but wasn't quick enough since we both say the same thing I miss read it opps! I did look at that plug chart don't know if you sent me there but great chart I book marked it for sure. Iam going to ignore the temps for now and concentrate on it running properly and when I'm happy with it I'll check the temps for the fine tuning to be sure the cabs r set even. I am going to take the spacers out and listen to it and go from there and I shall return with the results.
Thank you, Till then Mr.Bill

[mrbsyammy]

not coming off throotle fast enough

got carbs better but now it takes it awhile to go back to idol?
Till then

[motoman]

got carbs better but now it takes it awhile to go back to idol?
Till then

Hmmmm........'hang idle' scenario. Other than not being synced correctly, including idle mixtures, almost guatentee idle/pilot circuit isn't as THROUGHLY clean as you may think .