The inner spring and small seal was likely the issue on old cap if the outer rubber seal had no cracks in it
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ST1100 overheating
- Thread starter ak85lp
- Start date
The connector cannot be ordered from Honda. Carefully cut back the tape around the wires and inspect the wires and 4 crimped lugs. I found my problem was the red wire. The connector and the other crimps and wires were OK. I did the "Red Wire Bypass" for $10 and 10 minutes. Worked great so far (10K miles). Look at: www.st-riders.net/index.php?topic=7130.0
I did not do the Ignition Relay Bypass Modification toward the end of the explanation.
OP
OP
ak85lp
(Paul)
UPDATE
After my post last year I thought I had this problem beat but it returned this weekend.
Riding through a town the bike did get up to the higher temp and I did hear the fan kick in twice. By the time I got to my destination in town it had boiled over at the overflow bottle. I haven't had time to check it but I will look for no cracks in the overflow hose that I replaced last year and make sure the new rad cap is on tight.
I did not replace the thermostat and some research shows that if it does fail then it will stick open anyway. I don't mind replacing it if that turns out to be the issue but I was not able to find a suitable auto part number as the Honda OEM is supposed to be quite expensive.
After my post last year I thought I had this problem beat but it returned this weekend.
Riding through a town the bike did get up to the higher temp and I did hear the fan kick in twice. By the time I got to my destination in town it had boiled over at the overflow bottle. I haven't had time to check it but I will look for no cracks in the overflow hose that I replaced last year and make sure the new rad cap is on tight.
I did not replace the thermostat and some research shows that if it does fail then it will stick open anyway. I don't mind replacing it if that turns out to be the issue but I was not able to find a suitable auto part number as the Honda OEM is supposed to be quite expensive.
Certainly is the symptoms of a split in the overflow hose. A thermostat can also fail stuck closed, but this wouldn't cause boiling over from the overflow bottle. Loose rad cap would cause this as well.
I used a stat from an early 80's Honda civic, cost ?5,exact same stat, the oem stat was 50.
ST1100Y
Site Supporter
What about the O-ring for the t/stat case? Does the Civic one fit too?
I can't remember Martin,it was a few years ago,I posted about it at the time. I'll have to look back through my old posts,I don't remember replacing the 0 ring though I may have bought one for it in a local marine supply shop.
Here's the thread I was posting on at the time,it was 3 years ago,
https://www.st-owners.com/forums/showthread.php?40275-thermostat-replacement-on-91-st1100/page2
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