GS1150 Gas-hog.

[satchmo]

1984 GS1150EF. Recently purchased.

Ok. Some issues that need to be dealt with.

Gas consumption. My mileage plain stinks. 15L/120kms.

*edit* I should add I ran a bunch of seafoam through her with no discernible difference in performance.


Something's screwy.

Now here's the interesting bit.

She starts fine on choke. Comes off choke after about 1min, no problem. Idles fine. Goes fine. No flatspots, she'll go from 0-100km/hr in no time at all, pulls like a train.

But there is a bit of a sputtering noise at times when I'm at a steady pace (like there's too much fuel).

Now I haven't pulled the plugs to look at them yet, but in the event that they're showing too much fuel, what's the order I should look at things in?

Another thing to mention is that the reserve setting on the petcock doesn't seem to work. In the normal 'run' position, she'll suck down all the fuel in the tank until it's empty. Now there's no fuel in the crankcase, so is it possible that the petcock needs rebuilding and that this could be causing the excess fuel consumption?

I just find it odd that I would have the fuel consumption problems but not notice her running real rough or not starting or things like that.

Any ideas?

[Arkaloid]

I am wondering if that petcock is somehow rigged to be on 'prime' all the time and overwhelming your float valves, jsut enough to cause bad mileage, but not quite enough to drown out a sparkplug. OR..#2 carbs vacuum port is sucking fuel from that petcock as well.

[robertbarr]

My mileage plain stinks. 15L/120kms.

Wow, that's not even sane! That works out to about 18.8 mpg. I have an air conditioned Honda Civic that gets more than twice that!

When my venerable '79 GS850 got into its elder years, with about 54,000 on it, it would get around 27, and I thought that was outrageous.

No suggestions for a cure -- but that's one thirsty bike. Good lord...

[Joe Nardy]

Satch,

What do you have for intake and exhaust, i.e stock airbox, pods, stock exhaust, 4 into 1 system? If the bike is all stock you should easily get 40 mpg unless you're really flogging it. If it has pods, pipe, and jet kit that can drop significantly. My '83 1100E with pods, pipe, and stage III jet kit gets low 30's overall, dropping into the high 20's riding hard.

Thanks,
Joe

[crag antler]

Satch,

What do you have for intake and exhaust, i.e stock airbox, pods, stock exhaust, 4 into 1 system? If the bike is all stock you should easily get 40 mpg unless you're really flogging it. If it has pods, pipe, and jet kit that can drop significantly. My '83 1100E with pods, pipe, and stage III jet kit gets low 30's overall, dropping into the high 20's riding hard.

Thanks,
Joe

My 83 GS1100E, when it was running8-[ , would get anywhere from 40 to 50mpg, bone stock.
Pull the plugs and look. How well did the PO take care of the bike??
May time to peek at the carbs..

[renobruce]

I have noticed on mine that if the carbs are out of synch, the mileage goes down. But not as bad as yours. These 1150's are super sensitive to being out of synch. Check your plugs and air filter. Is the bike stock?

[first timer]

sounds like time for a carb and petcock cleaning, the carbs are probly plugged with crude and it is causeing bad milage, the motor is big enough that even with dirty carbs it could seem like it is pulling hard.

-ryan

[satchmo]

Satch,

What do you have for intake and exhaust, i.e stock airbox, pods, stock exhaust, 4 into 1 system? If the bike is all stock you should easily get 40 mpg unless you're really flogging it. If it has pods, pipe, and jet kit that can drop significantly. My '83 1100E with pods, pipe, and stage III jet kit gets low 30's overall, dropping into the high 20's riding hard.

Thanks,
Joe

Stock everything. 4-2 exhaust, stock airbox,.

[satchmo]

sounds like time for a carb and petcock cleaning, the carbs are probly plugged with crude and it is causeing bad milage, the motor is big enough that even with dirty carbs it could seem like it is pulling hard.

-ryan

Thanks guys.

I think this might be the route. Rebuild the petcock and clean and synch the carbs.

I have no idea how the PO took care of it because I got it at a dealer, it had been on their floor for a while.

[jimcor]

Clean the air filter and check the plugs/wires before you pull the carbs.

[earlfor]

Thats pretty unbelievable. :-) My 85 1150 with stock exhaust, derestricted airbox and jetted 1 step bigger still averages 43-45 mpg, which would be about 15L per 275 km.

The 1150 is particularly sensitive to carb synch and adjustement. A little bit off and it will run fine, but gas milage will drop by 40%.

Earl

Wow, that's not even sane! That works out to about 18.8 mpg. I have an air conditioned Honda Civic that gets more than twice that!

When my venerable '79 GS850 got into its elder years, with about 54,000 on it, it would get around 27, and I thought that was outrageous.

No suggestions for a cure -- but that's one thirsty bike. Good lord...

[satchmo]

Aight. Here's the plan (after I move this weekend)

Clean air filter, check/replace plugs.

See how she does.

Then petcock and carb cleaning/rebuild, followed by a carb sync. I think this oughta get me into the right ball park.

[renobruce]

Aight. Here's the plan (after I move this weekend)

Clean air filter, check/replace plugs.

See how she does.

Then petcock and carb cleaning/rebuild, followed by a carb sync. I think this oughta get me into the right ball park.

Before you pull the carbs off, cuss like a sailor for at least one hour. Then pull the carbs. It won't be so bad that then. They are a real biatch. I use a long screwdriver wrapped in a towel to help pry them off and on.

[robert_r_lefebvre]

When you synchronize your carbs

I noticed you live in Ottawa. I have a carb synchronizer if you would like to borrow it. I've got a 1983 GS1150EF and it gets 300Km to the tank, including reserve.

If you want to borrow it you can send me an email, I'm in Kanata.

Bob