2001 ST1100 overheating

OK, i know this is an known issue, and reading thru the threads I see a common thread of replacing the overflow tube and replacing the radiator cap and O-ring.

Let me describe my situation to make sure its probably the same issue.

I only have an over heating issue when i am in stop and go traffic or sitting still. The temp can be in the 50-60 and the temp will start to climb at stop lights. Of course the hotter it is the quicker it climbs. I have found that as it heats up i start to boil my clutch and it starts to slip and eventually not work at all in higher temps.

I KNOW i have seen LOTS of threads on here on the recommended fix... but I thought there was a sticky or something that had a step by step list on how to deal with it. But I can't find it now.

Opinions welcome and please pint me in the right direction. I youtube video would be GREAT!

After reading more, i thought I should mention it doesn't leak, and I have no fluid overflow issues. I had it gone thru at the Honda dealer after my 2013 long trip, according to what services should have been done for the mileage on it... don't remember off the top of my head what that was, it was about two years ago.

the over heating began on the 2013 long trip in hot stop and go traffic, and now has progressed to any stop and go traffic. it isn't "immediate", it takes 2 - 3 stopping at lights before it gets really high, and as soon as i start moving over 25mph it starts to cool down.

Any links would be helpful, and any parts list would be great too...

So how high does the needle get? Into the red zone? Halfway or even 1 o'clock is normally seen as the highest a properly functioning system will read. Does the fan come on at that point?

Does the fan come on while sitting at the lights.... If it does, then the system sounds normat to me, though you may be advised to check that the cooling system is full by removing the radiator filler cap (Not the overflow bottle).

The clutch problem sounds like trapped air or moisture in the system. Try replacing the clutch fluid with new (DOT 4 Brake fluid)

Avtrician said:

Does the fan come on while sitting at the lights.... If it does, then the system sounds normat to me, though you may be advised to check that the cooling system is full by removing the radiator filler cap (Not the overflow bottle).

The clutch problem sounds like trapped air or moisture in the system. Try replacing the clutch fluid with new (DOT 4 Brake fluid)

Click to expand...

+1 Check to see if the cooling fan is running while standing still. Happened on my 1100, in my case it was a bad connection. Test procedure is as follows:
If fan is not running, unplug the fan and juice the connector(polarity doesn't matter at this point), if fan comes on, then the fan is not the culprit. Next, plug fan in, unplug temp sensor, jump the connector, if fan comes on, then it's probably the sensor. If not, see if you have power. If you do, it's probably a bad wire, if not, check fuses. If fuses good and you have power, then it's probably a bad wire between the fuse block and the sender. If no power, probably a problem with the fuse block(assuming everything else is working) The cooling fan circuit is pretty simplistic in it's design, so it's not hard to diagnose.

Now, if the fan comes on as it should, then it's possible it's a number of things. Low coolant(check when rad cold at filler) Thermostat(stuck closed-replace with fail/open type) clogged radiator(have local rad shop clean) or bad water pump(I forgot where it's located on the ST1100, maybe belt driven off the timing belt?)

As far as the clutch, if the motor is running hot, it's possible that the fluid has absorbed some water over time (dot3/4 fluid is hygroscopic) I'd flush and refill the system to give you better function. Water in the system lowers the boiling point of the fluid dramatically

I am planning on checking on the fan functionality this weekend if I get time, it sounds pretty easy to check after reading a ZILLIONS posts last night late... Ill let you guys know what I find.

As far as how "hot it gets"? almost to the red and I don't notice it going down as described when a fan comes on.... and I don't KNOW that i hear a fan or not either (it may or may not be coming on).... ill check functionality anyway and post.

I have ordered a new Honda OEM radiator cap and OEM thermo switch, and I plan on replacing the return tube with a good high quality line and real clamps regardless of whether the fan is working or not.

I will also at that time make sure the radiator fluids are working correctly and replace the clutch fluid (i am planning on having the local honda shop do those two parts as I think they can do it better then i)

I have another long trip in the plans with my son in the heat of the summer, so I really want to make this as little a problem as possible before I go.... but more on that later... don't want to jinx myself by describing it yet...LOL

Is the overflow tank full?

The fan switch sensor will not "sense" hot air and turn the fan on. The cooling system (radiator and block) must be full of coolant.

check that the cooling system is full by removing the radiator filler cap (Not the overflow bottle)

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+1

The firST thing to do.

Report back.

John
via iPhone

I have installed a switch to turn the fan on ...... it gets warm here in Paradise....
About the only place a "scotchlok" is okay....the temp sender completes a ground circuit, so I ran a wire from the sender wire to a switch to ground....
I suggest that you address and fix the problem, because it's a bummer being towed....
Have fun!

Ron said:

Is the overflow tank full?

The fan switch sensor will not "sense" hot air and turn the fan on. The cooling system (radiator and block) must be full of coolant.

Click to expand...

Will do this first!

Then check to make sure the fan/thermo switch is actually working.

check that the cooling system is full by removing the radiator filler cap (Not the overflow bottle)

John OoSTerhuis said:

+1

The firST thing to do.

Report back.

John
via iPhone

Click to expand...

This is the guy you should be listening to, the overflow can be full or empty but if the tube from the radiator is cracked you have no idea if the Radiator is full.
You need to get to the Radiator cap.

And to do that from what I can tell, is to remove most the plastics and the right side locking "pockets"??

superdiver said:

And to do that from what I can tell, is to remove most the plastics and the right side locking "pockets"??

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That about sums it up. From there, you can access the thermostat housing, radiator cap and overflow tube...if you have a great sense of humor.
You will have adequate access to the upper end of the tube, it's just behind the locking compartment...easy to remove all the way back to the reservoir, which you will have to remove to access the lower end of the tube.
Radiator cap access is tight, but workable. Push down and unscrew a partial turn. If it's been there for years, have your kids leave the garage, but it can be done without breaking anything. Look at the underside of the cap carefully for cracked seals (2 of them) and crud build up. The cap can leak vapor and therefore pressure.
The upper radiator hose end can be accessed easily. If you need to remove the whole assembly, it will be easier to remove the upper cowl...much less chance of breaking something.

superdiver said:

And to do that from what I can tell, is to remove most the plastics and the right side locking "pockets"??

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Yes. You knowingly purchased a fully faired motorcycle. Don't let the simple task of removing tupperware deter you from doing essential maintenance. It gets easier and comfortingly familiar the more you do it. Think of Zen And The Art Of Motorcycle Maintenance.

John
via iPhone 6

John OoSTerhuis said:

You knowingly purchased a fully faired motorcycle.

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If they could have done without that one pocket panel screw under the top shelter the time required would be reduced by about 3x. I've done it enough times now that I can rip all that stuff off in about 5 minutes anyway, but every time I do I laugh at the way Honda designed the access to the rad cap.

FWIW, my FZR1000 was a fully faired motorcycle and required the removal of 2 or 3 screws to access the rad cap. It probably took me as long to type this sentence as it did to get access to the rad cap on that bike.

dwalby said:

If they could have done without that one pocket panel screw under the top shelter the time required would be reduced by about 3x. I've done it enough times now that I can rip all that stuff off in about 5 minutes anyway, but every time I do I laugh at the way Honda designed the access to the rad cap.

FWIW, my FZR1000 was a fully faired motorcycle and required the removal of 2 or 3 screws to access the rad cap. It probably took me as long to type this sentence as it did to get access to the rad cap on that bike.

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I still think someone should design a bike with the plastic being hinged somehow, so you could just unlatch it and move it out of the way to access what you need, without having to disassemble the bike. Kinda like a car hood. But as John pointed out, we knew, or should have known, what we were signing up for. I need to remind myself of that now and then..

Joseph/TX said:

But as John pointed out, we knew, or should have known, what we were signing up for. I need to remind myself of that now and then..

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you're more forgiving than I am. I think its a stupid design flaw that no customer should have expected just because the bike has a fairing.

dwalby said:

you're more forgiving than I am. I think its a stupid design flaw that no customer should have expected just because the bike has a fairing.

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Today, yes, it would be unforgivable in a new bike.
But in the days when this bike was designed, liquid cooling was in it's infancy, and the few bikes that had fairings were were normally just an external skin. So I can be a lot more accepting of it on a "poineer" design.

Fatjock said:

Today, yes, it would be unforgivable in a new bike.
But in the days when this bike was designed, liquid cooling was in it's infancy, and the few bikes that had fairings were were normally just an external skin. So I can be a lot more accepting of it on a "poineer" design.

Click to expand...

Honda has produced water-cooled Gold Wings since 1975, and they weren't the first, Suzuki had the water buffalo in the early '70s. The concept of a radiator wasn't new to Honda, or anyone else in the industry when the ST1100 was designed.

John OoSTerhuis said:

Yes. You knowingly purchased a fully faired motorcycle. Don't let the simple task of removing tupperware deter you from doing essential maintenance.

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LOL! Yep, complaining on a high comfort level here... ;-)
One key-word of maintenance is essential, the other though: periodically...
Seriously, how often does one need to dive below the Tupperware of an ST1100? Once a year maybe... proper maintenance given of course, and that's the 3rd key-word... M2C...