Cylinder temps?

[Bartman]

Does anyone know what temperature the exhaust pipes coming out of the head should be?

I measured mine on the first downward curve using a laser thermal gage. My #1 & #4 are running around 325 and #2 & #3 are at 265.

I swapped coils and ignition module with no change. I have been going through this bike for a year and just was able to ride it Sunday when I checked and found this issue.

I have the same emulsion tubes and jets in all four carbs.

I also thought about the valve clearances and may have to check them one more time. The shims were changed a few months ago. I did a thread on this because I tried to swap a shim from one place to another and found that you shouldn't rotate the motor without a shim in the bucket. So maybe even though the correct shim was put in, the buggered up cam has changed the actual required need.

Before I go back into the valves I plan on enriching the 1&4 a small amount to see if those will cool down....

It is running the best that I have seen at this time. It might be best to ride and not worry about it?

What temps do you see?

[motoman]

Does anyone know what temperature the exhaust pipes coming out of the head should be?

I measured mine on the first downward curve using a laser thermal gage. My #1 & #4 are running around 325 and #2 & #3 are at 265.

I swapped coils and ignition module with no change. I have been going through this bike for a year and just was able to ride it Sunday when I checked and found this issue.

I have the same emulsion tubes and jets in all four carbs.

I also thought about the valve clearances and may have to check them one more time. The shims were changed a few months ago. I did a thread on this because I tried to swap a shim from one place to another and found that you shouldn't rotate the motor without a shim in the bucket. So maybe even though the correct shim was put in, the buggered up cam has changed the actual required need.

Before I go back into the valves I plan on enriching the 1&4 a small amount to see if those will cool down....

It is running the best that I have seen at this time. It might be best to ride and not worry about it?

What temps do you see?

If havin' the carbs off, may wanna check float levels for all eight being identical setting.

[Bartman]

I put the carbs in my table vise and used the clear tubes attached to zerk fittings in the bowls. Let them sit for hours to make sure all were level and didn't leak.

Still, the temps are different at start up idle and after riding hard the last mile home.

So the question that needs to be answered is what temp should I see?

[Cuda 69]

could it be 1&4 are running lean,or maybe 2&3 running rich? Not sure what the temp of the pipes should be.But will be interesting getting the answer.

[motoman]

could it be 1&4 are running lean,or maybe 2&3 running rich? Not sure what the temp of the pipes should be.But will be interesting getting the answer.

Might wanna pull those plugs for a burn check. If the cyls. you might suspect lean and grey on plug electrode, would consider correcting issue as they don't run well with ventilated pistons.....

[Aches n Pains]

Bartman,

I posted a similar question not long ago under the title Head Temperatures. http://www.xs11.com/forum/showthread.php?t=38546

Got a few responses and the general conclusion is that a reading in the 200-250 degree range is OK after a ride with the inside cylinders running hotter than the outside. Are you checking after a ride or after idling on the center stand?

I agree with the others that your situation (outside hotter than inside) suggests the outsides are running lean and the insides running rich. Might want to check the jets to be sure they are correct. Sometimes guys will try to correct the heat problem in the center by re-jetting rich.

Aches n Pains

[TADracer]

Alot of variables can affect pipe temp so I never put alot of weight in a pipe temp measurement difference between pipes unless it is a big swing.

If you use a laser then you cannot just aim it at the pipe. Start your measurement as close to the head as possible and slowly sweep across the pipe and from only an inch or two away. Watch the gauge and take the highest reading.

[Bartman]

I have checked at both start up idle and after a very hard run down the road. All times that I check the inside were 50 ~ 70 cooler than the outside ones. Backwards from what I was expecting.

I only checked at the turn of the pipe which is about 2 inches from the exhaust port. I also was shooting the pointer at the distance of the front forks. I will check again by the spark plug and at the exhaust port and head next time.

If the temps are different at start up idle and after a long run. And if it is running lean on 1 & 4 and rich on 2 & 3 then both the idle and the mains would both have to be wrong????

But at both conditions (idle & running) then it might be the cams needing to be checked one more time.

[jayel]

single wall pipe or double wall will effect it, measure the head temp as close to the port as possible also next to the plugs expect 240 to 265 range

[CaptonZap]

Not to introduce un needed complications into this puzzle, but are your header pipes stock, with an inner and outer pipe, or a single wall after market type.
If they are the two wall type, there could be some issues with the inner pipe on 1&4.
Assuming they are the two wall type, a crack in the weld between the two, allowing gas bypass into the intermediate space, could cause that temperature difference.
Look on the bottom of the pipes, down where they meet the collector, and you should see a small drain hole in the bottom of the head pipes. Start the engine, and see if gasses are forced out the hole. If there are, the interior welds are compromised, allowing leakage.

[Bartman]

I believe that they are after market and when I was putting new stud bolts and gaskets into the exhaust I didn't see any inner tubes. I believe that they are single pipes.

I stayed home sick today and could have spent my time oh so wisely but I just haven't had the energy to touch the bike. I hate laying in bed and thinking about what I need to be doing! Hopefully tomorrow night I'll feel better.

[CaptonZap]

I believe that they are after market and when I was putting new stud bolts and gaskets into the exhaust I didn't see any inner tubes. I believe that they are single pipes.

In that case, as the others suggested, it is timing or carburetion.
Although, the temps seem low all around, given that the exhaust temperature of the gases will range from 500 to 600 at idle, to 1100 - 1300 at full song. And two or three inches from the head on a single wall pipe should show a higher temperature.
Boil a dark pan of water, and shine the laser on the side of the pan and see what temp you get displayed. CZ

[Rasputin]

Look on the bottom of the pipes, down where they meet the collector, and you should see a small drain hole in the bottom of the head pipes. Start the engine, and see if gasses are forced out the hole. If there are, the interior welds are compromised, allowing leakage.

Not sure what years these were on which bikes, but not all of them have the plug. I thought these plugs were for exhaust gas sniffers to go in for setting carbs. I only have one set that has them on it and I have never taken them out. Are they in fact drain plugs or are they access to the exhaust gases in that pipe?
The idea of the break in the inner wall is very valid in my mind and could be the source of the problem.
I do not know which exhaust the OP is using as after market can be so much different than OEM. Pictures or a description of the exhaust may help narrow down the issue.

[jayel]

they are to let moisture out so the pipes don't rust, shoundn't be any puffing as that indicates a exhaust leak

[XS1100_OEM4ME]

Oem

they are to let moisture out so the pipes don't rust, shoundn't be any puffing as that indicates a exhaust leak

I think the pin holes in the early exaust were as said. I belive the bolt plug's go all the way through and were for meeting emission standards on 80+ bikes JIMHO