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Hot exhaust headers on RT

schuk

New member
I've had my 2000 R1100RT for less than a year so I'm still getting to know the bike. Recently, when I had the bike running in the open garage, I noticed that the exhausts were red hot but wrote it off to having it running but stationary (no air cooling). The temp gauge was in the normal range when I shut it down.

About a week after that, the Mrs. and I took it out for a ride not suspecting any problems, but now I've noticed that it apparently got so hot during the ride that it blistered the paint on the fairing near the exhaust headers. That just about killed me to think that I did that to my once pristine RT! Once again, the engine temp gauge never indicated a problem during the ride.

Do I need to check the valve clearances or what would cause so much heat build-up in that area without the temp gauge reflecting it? Any ideas or solutions would be greatly appreciated since I don't want to ride it until I resolve the problem.

Thanks
 
How long was it running in the garage?! I have never experienced that, but I never let my bike idle long enough to get the headers red hot, regardless of what the temperature gauge says. Also, BMW headers are single wall tubing, so the heat from the exhaust ports goes right into the headers. That guage measures oil temperature, which may have very little to do with what is happening at the exhaust ports.

As far as letting an oilhead warm up before riding, if that is what you were doing, there is absolutely no reason to do so. If I am assuming wrong, sorry bout that. When I am ready to go, in any weather, I have all my gear on and mount the bike before starting it.

Once it starts, and the oil pressure light is out, which is nearly immediate, I get in gear and start moving. Been doing that for 16 years and over 156,000 miles with NO issues with the bike whatsoever.
 
ANDYVH,
I generally don't warm it up before riding either but the bike had been sitting for about a month and a half and I had it running to just lube it up and charge the battery a bit. I suppose that it had been idling for about 5 minutes the first time I noticed the glowing pipes. Then prior to noticing the blistered paint near the headers, we had actually been on the open roads with plenty of air and oil cooling.

I usually watch the oil temp gauge closely just because the nature of the beast to heat up that oil at long stop lights in hot weather.

I appreciate your response and your thoughts, however I feel that there might still be somethings else I need to address ... just not sure what it is.
 
Running to lubricate things ought to take no more than 10 seconds. Running to charge the battery stationary in a garage is a way to ruin an engine and the paint.

Mechanically, the headers will get hot sooner than anything except the exhaust valve heads. The rest of the engine has enough mass to take a bit longer.

Those factors aside, the exhaust system, valves, and pistons can get hot if the mixture is too lean but that probably is not the actual problem in this case.
 
Reference your BMW R1100RT owners manual - page 44.

It states: NOTE: NEVER ALLOW THE ENGINE TO WARM TO ITS NORMAL OPERATING TEMPERATURE BY LEAVING IT RUNNING AT IDLE. RIDE AWAY IMMEDIATELY AFTER STARTING THE ENGINE.

AVOID RIDING FOR EXTENDED PERIODS WITH THE COLD-START LEVER (LABELED CHOKE) ON. RETURN IT TO POSITION 0 AS SOON AS THE ENGINE STARTS TO RUN SMOOTHLY.

Running the engine at idle with the choke engaged will cause a pipes to glow in short order due to an overly lean air/fuel mixture. Even at a couple of bars, it can cause significant damage to the side panels. This is a common mistake at high costs, since each side is over $750 to replace.
 
Hi,

Unfortunately this is a fairly common mistake with air and oil cooled BMWs . When shopping for my 99 R1100RT I looked at a couple of choices where owners had done the exact same thing as you had. I asked the dealer about this and she said she has heard of people leaving the bike on fast idle to charge the battery, only to return later to melted fairing and in one case, a fire!

Yes, owners manual says start up and get rolling.
 
red

Looks like Paul is the only one who read the OP initial query - everyone else is jumping on him about idling the bike in the garage. The OP noted that the headers got so hot DURING A RIDE, that it blistered the body panels.
It sounds like the bike is running too lean. If you had raw fuel pouring into the cat, you would get an overheated cat and the panels would blister down there. If the pipes are glowing under normal operation at normal speeds, you probably need to set the valves and balance the TB to see if that helps. I know that Randy from the east coast of FL had a hot header problem on his 1150 GS, and he eventually had to take it to the dealer to have it sorted because none of us FL boys (many of whom have a lot of experience with these bikes) could figure out what was wrong (and we STILL don't know).
 
Looks like Paul is the only one who read the OP initial query - everyone else is jumping on him about idling the bike in the garage. The OP noted that the headers got so hot DURING A RIDE, that it blistered the body panels.
It sounds like the bike is running too lean. If you had raw fuel pouring into the cat, you would get an overheated cat and the panels would blister down there. If the pipes are glowing under normal operation at normal speeds, you probably need to set the valves and balance the TB to see if that helps. I know that Randy from the east coast of FL had a hot header problem on his 1150 GS, and he eventually had to take it to the dealer to have it sorted because none of us FL boys (many of whom have a lot of experience with these bikes) could figure out what was wrong (and we STILL don't know).

Nobody jumping on Paul - you must mean Schuk. He's getting good advice. Schuk stated, "Recently, when I had the bike running in the open garage, I noticed that the exhausts were red hot but wrote it off to having it running but stationary (no air cooling). " Schuk is making a common error by new owners warming the bike with the choke engaged. Although he stated he noticed the blistering after a ride (no way to see pipes during the ride), this would not occur from running overly lean or rich mixtures. This only occurs after running the bike with the choke on usually in the stationary position.

The ECU is not adjustable, so it can't accidently run rich or lean unless he's running a Techlusion. Valve adjustments and throttle body adjustments have nothing to do with the amount of time fuel injectors stay open or closed.

I've ridden my R1100RT for 130,000 miles to include about 10,000 miles in Washington DC standstill traffic. At times, my RT was running 9 bars. The fairing even at 9 bars is not blistered and I was at the time running the bike overly rich with a Techlusion.

Again I, like many on this forum, have seen this problem many times. Every time, its idling the bike with the choke on.
 
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Wait a minute! I'm Paul and I didn't do it. I can't figure out what shcuk's first name is but the reference to "Paul" was to me.

Back to talking paint.
 
To Paul

"...Looks like Paul is the only one who read the OP initial query ..."
I do believe that was a compliment to Paul Glaves and his ability to read and his outstanding comprehension.
"...Valve adjustments and throttle body adjustments have nothing to do with the amount of time fuel injectors stay open or closed..."
Maybe, but the first step in troubleshooting something like this is to ensure there isn't an obvious cause that the OP may be overlooking. For all I know, a burned exhaust valve might be causing the problem. As I mentioned earlier, we couldn't figure out what caused one (not both, but one) of the pipes on Randy's bike to glow when we were working on it, and he eventually had to go to the dealer to get it sorted. I know that neither my RS nor my RT have glowing headers, and I have seen 10 bars on both of them.
 
Hmm,...Flars,....here is what I read in the OP:

"Recently, when I had the bike running in the open garage, I noticed that the exhausts were red hot"

That, to me, sounds like the bike was idling in the garage. We're not jumping on him for a potentially bad practice, but we are pointing out a misconception some have about starting bikes. I have at times, briefly let my 94 RS idle in the garage while I quickly did minor adjustments on the throttle bodies, and my pipes and cat never showed any indication of orange or red hot. Now, my bike is an early 94 model, and it is fitted with a Techlusion, so it runs richer than stock. Later models idle very lean which tends to build heat quickly and substantially. So, like the owner manual says, do not let the bike idle for any extended period. Even five minutes is an extended period.

Also, letting the bike idle really does not charge the battery. Alternator output at idle is not high enough to charge the battery. Charging really doesn't happen till a constant highway speed with the engine turning a consistent 3,000+ rpm. So the recommendation remains that there is no reason to let the bike idle and "warm up" before riding.
 
I read years ago, the SAE said the best way to warm up an engine is to start it, then drive away at a slow or moderate rate of speed. This cools the engine, and gets the oil pressure up to lubricate the engine.
 
Hmm,...Flars,....here is what I read in the OP:

"Recently, when I had the bike running in the open garage, I noticed that the exhausts were red hot"

That, to me, sounds like the bike was idling in the garage. We're not jumping on him for a potentially bad practice, but we are pointing out a misconception some have about starting bikes. I have at times, briefly let my 94 RS idle in the garage while I quickly did minor adjustments on the throttle bodies, and my pipes and cat never showed any indication of orange or red hot. Now, my bike is an early 94 model, and it is fitted with a Techlusion, so it runs richer than stock. Later models idle very lean which tends to build heat quickly and substantially. So, like the owner manual says, do not let the bike idle for any extended period. Even five minutes is an extended period.

Also, letting the bike idle really does not charge the battery. Alternator output at idle is not high enough to charge the battery. Charging really doesn't happen till a constant highway speed with the engine turning a consistent 3,000+ rpm. So the recommendation remains that there is no reason to let the bike idle and "warm up" before riding.

:thumb
 
The only bikes I ever let "warm up" were the 70's vintage Hondas I used to ride. They are notoriously cold-blooded beasts that only run on the choke at 3,000 rpm or barely ran at all until warmed up. On most of them I tweaked the pilot/idle jet circuit to richen them up a bit for easier/quicker starting. Did that with my brother's 81 Yammy XJ650RJ and it starts great, warms quickly, he follows my guideline of "ride it as soon as possible after starting" and now six years after I installed the jet-kit he has not had one issue of hard starting or failed battery, gummed up carbs, etc.

On all my vehicles, even though I live in Green Bay, WI, I start them and drive/ride as soon as the oil pressure light goes out. Never had any engine issues with any of my vehicles.
 
The ECU is not adjustable, so it can't accidently run rich or lean unless he's running a Techlusion. Valve adjustments and throttle body adjustments have nothing to do with the amount of time fuel injectors stay open or closed.

I

I'll quibble a little bit. The system does not measure air flow. It assumes air flow based on the position of the single TPS on the left throttle body. The ECU assumptions about air flow depend on the TPS idle value and range, the proper adjustment of the valves, and the proper synchronization of both throttle bodies. The O2 sensor reads the exhaust stream and makes some correction some of the time.

If valves are set out of spec, or if there are deposits on valve heads then air can be constricted but the ECU doesn't know it. If the two throttle bodies are not synchronized then one can be rich while the other is lean. And if there are gums or crud partially obstructing a fuel injector that cylinder will get less fuel even though the injector is staying open the right number of milliseconds.

So there are all sorts of variables that can effect mixture without a Techlusion or any other aftermarket add-on. Most of them are dealt with with a complete proper "tune-up">
 
I'll quibble a little bit. The system does not measure air flow. It assumes air flow based on the position of the single TPS on the left throttle body. The ECU assumptions about air flow depend on the TPS idle value and range, the proper adjustment of the valves, and the proper synchronization of both throttle bodies. The O2 sensor reads the exhaust stream and makes some correction some of the time.

If valves are set out of spec, or if there are deposits on valve heads then air can be constricted but the ECU doesn't know it. If the two throttle bodies are not synchronized then one can be rich while the other is lean. And if there are gums or crud partially obstructing a fuel injector that cylinder will get less fuel even though the injector is staying open the right number of milliseconds.

So there are all sorts of variables that can effect mixture without a Techlusion or any other aftermarket add-on. Most of them are dealt with with a complete proper "tune-up">

Have you ever seen any of these variable you discribe above result in blistered side panels on an RT? I've seen side panels too many times to count on well-tuned RT blister at only 3 bars at idle by leaving the choke on. However, I've never seen an RT blister side panels even out of tune at 9 bars in standstill traffic in Washington D.C. Been there, done that for a full year on my RT with 133,000 miles and the side panels are not blistered.

Again, the only logical reason for this problem is self evident in the owners own statement stating he idled the bike in his garage. Although he doesn't say it, the only way to get the headers to glow as desribed is by engaging the choke at idle.
 
Have you ever seen any of these variable you discribe above result in blistered side panels on an RT? I've seen side panels too many times to count on well-tuned RT blister at only 3 bars at idle by leaving the choke on. However, I've never seen an RT blister side panels even out of tune at 9 bars in standstill traffic in Washington D.C. Been there, done that for a full year on my RT with 133,000 miles and the side panels are not blistered.

Again, the only logical reason for this problem is self evident in the owners own statement stating he idled the bike in his garage. Although he doesn't say it, the only way to get the headers to glow as desribed is by engaging the choke at idle.

I'm not arguing that point at all. See my original post. These bikes should never be allowed to sit at idle very long, and certainly not at fast idle. But he also originally posted that the pipes glowed going down the road and I have seen glowing pipes from lean mixtures, not at highway speeds but at neighborhood speeds. The identified cause was throttle body imbalance with one side rich and the other lean.

Related, but as an aside, the basis for BMW discontinuing the R1100RSL in the US before they did so in Europe is not urban legend. An owner started his bike, went in the house, answered the telephone, had a long conversation, and came back out to find the bike, then the garage, and soon the house on fire. The size of the print of the warning in the manuals got bigger after that I am told.
 
Schuk...is the blistering on your side panels on one side or both?

Here's an interesting fact. Last winter, I was adjusting the throttle bodies on my R1100RT (side panels off). While warming the motor to five bars, I decided to see just how hot the header actually get with the choke full on. At three bars with the choke full on and the pipes glowing, my IR Thermometer registered 500 degrees. It could have actually been hotter, since my IR gun range is -4 to 500 degrees. With the choke off at five bars, both headers were around 300 degrees. Both throttle bodies were very close to being in synch. It would be a good experiment to intentionally adjust the throttle bodies out of synch and record the difference.
 
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I'm having this same problem with a hot header blistering my paint

I'm not arguing that point at all. See my original post. These bikes should never be allowed to sit at idle very long, and certainly not at fast idle. But he also originally posted that the pipes glowed going down the road and I have seen glowing pipes from lean mixtures, not at highway speeds but at neighborhood speeds. The identified cause was throttle body imbalance with one side rich and the other lean.

Related, but as an aside, the basis for BMW discontinuing the R1100RSL in the US before they did so in Europe is not urban legend. An owner started his bike, went in the house, answered the telephone, had a long conversation, and came back out to find the bike, then the garage, and soon the house on fire. The size of the print of the warning in the manuals got bigger after that I am told.

I know this thread is almost two years old but I'm having this same problem. I took my side panels off, sanded and repainted my crispy shark fins, and I also wrapped my headers. Got her all back together today I went on a 10mile mixed speed typical ride. The right side (if I'm sitting on the bike) seems to be the issue. I did not let it sit and idle, my oil temp was never above 5 bars, and it seemed to be running great. I got back home directly in the garage and shut her right off. Got off the bike and too that same side and the fin and the fairing next to the header was so hot I couldn't hardly put my hand on it. WTF is going on. I just had the valves and injectors done last fall. I replaced the plugs when I first got the bike. Went from Bosh R6 787 to NGK BKR7EKC-N. could that have anything to do with it? This is driving me nutz! I love this bike and I just want her fixed...
 
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