Gas Smell

Joined
Aug 15, 2013
Messages
32
Location
El Paso, TX
Bike
1993 ST1100
When I bought my ST1100 it had a new gas cap. The new gas cap requires quite a bit of force to close and initially I wasn't closing it completely and had a strong gas smell even noticeable when riding. After learning to tighten my gas cap down properly, the issue was resolved. Sounds obvious and simple, but that's what was getting me :eek::
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,218
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
If your ST1100's gas cap is hard to close, smear some grease between its gasket and the metal cap itself. In other words, the backside of the gasket.

John
 
Joined
Aug 15, 2013
Messages
32
Location
El Paso, TX
Bike
1993 ST1100
If your ST1100's gas cap is hard to close, smear some grease between its gasket and the metal cap itself. In other words, the backside of the gasket.

John
Will any type of grease do or is there one more compatible/safer for the materials involved?
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,218
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
Most any grease will work fine. Over the years I've used regular auto bearing grease, Phil Wood waterproof bicycle bearing grease, 3% moly grease, etc.; whatever I had at hand. Just a light smear will work for ages.

Edit: I wouldn't use silicone grease based on comments by others smarter than me on these matters.
 
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OP
OP
Joined
Jul 23, 2012
Messages
36
Location
western Montana
Bike
'91 ST1100
gas smell update- solved

For those of you who had same/similar problem...

Awhile ago I had posted threads on a gas smell issue on my '91 1100.

Well, I found out what was going on. The outlet hose on the quad fitting that ties the carb. overflow tubes together was coming off as I rode the bike, even with the "spring clip" installed. That particular fitting (at least on my bike) does not have any type of barb and is smooth. My guess is with vibration & air turbulence through this area it was enough to allow it to slide off. Of course you would not see this without taking out the gas tank and there it was. I have now stabilized that hose/connection-- no more smell.

FYI
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,218
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
Are you talking about the hoses and nipples on the bottom of the individual carbs, the bottom of the float bowls? Those are for draining the carb bowls. See page 5-18 in the service manual. If that's where your gas leak is originating you need to snug up the drain screws. HTH

JOHN
 
OP
OP
Joined
Jul 23, 2012
Messages
36
Location
western Montana
Bike
'91 ST1100
Yes, from looking at my shop manual this is the drain hose circuit. That said, it is the large outlet hose that kept(apparently) sliding off the plastic 5-way fitting. Also, what I did was what was mentioned, however, the gas smell going away. Related to what I wrote previously, the only time I would get the smell was approx. 3 to 4 minutes after I shut off the bike, now nothing. However, the weather here in western Montana is cooler now, so, it may very well not be related to this at all.(??)

I guess to be sure, I should probably remove the tank oneeeee more time. Can I get to all the drain screws without removing the carbs? I do have the pair system removed.

Thanks
 
Joined
Jul 28, 2007
Messages
3,119
Location
finger lakes ny
Bike
1999 ST1100
STOC #
7959
Can I get to all the drain screws without removing the carbs?
Yep, but good luck. You need a long regular scewdriver, flashlight and JUST THE RIGHT VIEWING ANGLE to access them. Maintenance covers and fairing pockets off.
 

John OoSTerhuis

Life Is Good!
Joined
May 10, 2005
Messages
5,218
Location
Bettendorf, Iowa
Bike
1991 SSMST1100
STOC #
1058
No need to pull the carbs. Like I said, page 5-18 in the Honda ST1100 Service Manual. My early edition didn't have the page but my good dealer gave me a copy:

CarbDrainP5-18 GS.jpg
 
OP
OP
Joined
Jul 23, 2012
Messages
36
Location
western Montana
Bike
'91 ST1100
No need to pull the carbs. Like I said, page 5-18 in the Honda ST1100 Service Manual. My early edition didn't have the page but my good dealer gave me a copy:

CarbDrainP5-18 GS.jpg
K, will do. From what you sent it looks like I won't have to remove the tank at all. (?) Looks to be an easy(pretty much) fix. Will do this weekend.

Thanks again...

B
 
Joined
Dec 22, 2009
Messages
68
Location
Nanaimo BC
Bike
1998 ST1100A
STOC #
434
OK, I'm going to revive an old thread here just to see if anyone found the cause of their gas smell...
My 98 has always had it, deleted the vacuum switch no change... I hotwired my fuel pump for a few minutes with the bike off and no smell! ( this pretty much eliminates the carbs as a source I believe)
It only stinks after it's been ridden and I park it....
 
Joined
May 20, 2015
Messages
4
Location
Bellevue Nebraska
Bike
1994 Honda ST1100
Robert and others - I purchased a '94 ST1100 with less than 15,000 miles about a month ago and it's in perfect shape...except for a strong gas smell after I ride. I've read threads and posts regarding this issue and the answer is certainly not "one size fits all". I get a very strong gas smell only after I've ridden my ST and stored it in my garage. The WX (weather) has been in the 30s to 50s, so it's very cool WX. That being said, I should probably start working from the easiest to complex by taking a look at my fuel cap first. It goes on very hard and I've caught myself not putting it on all the way at the gas station. I would like to think it's just a gas cap problem, but it's probably a vent hose, fuel line issue. Please let me know how you resolved this issue guys - thanks!
 
Joined
Aug 10, 2015
Messages
2,029
Location
Fort Worth, Texas
Bike
91 ST1100/06 ST1300
I had the same symptom with my 1991 which had sat up for 20 years or so. Carbs rebuild, among other things, and I got the raw gas smell after rides and with a partial tank on a hot day. I found the vented gas cap was plugged so I replaced it and the hose. Also checked the vacuum petcock (on the right of the fuel tank right by the fuel filter and found the rubber diaphragm and spring extremely floppy, but no holes. I suspected it may have been allowing gas to run into the carbs after shut down, under pressure of the hot/warm gas in the tank. Rebuilt it with a K&L kit. Anyway, the smell went away. Since I did both changes at the same time, I have no idea for sure which one was the problem. Could have been both.
 
Joined
Jun 3, 2006
Messages
3,514
Location
British Columbia
Bike
2021 RE Meteor 350
look at my fuel cap first. It goes on very hard
I think everyone would say they have run into that gas cap being really tough to turn issue. The rubber gasket on the cap needs a tiny smear of grease on the underside of it, that is, between the cap and the gasket, not between the gasket and the tank. I usually have to do this once or twice a season. Makes a huge difference in ease of removing/installing the cap.
 
Joined
Feb 11, 2018
Messages
14
Location
Oside ca
Bike
ST1100
I used to smell gas after I rode it to work and back. I eventually found a split fuel line to a carb, could only see it with bike running when I pulled on the hose. Does your bike make a weird sighing noise after you turn it off? Mine does. Probably a pressure relief, just sounds funny though.
 
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Joined
Feb 11, 2018
Messages
14
Location
Oside ca
Bike
ST1100
I had a similar issue where I would smell gas after driving to work and back. Turned out to be a slit fuel line to a carb. I could only see it with bike running when I pushed on the hose.
 
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