GS1100G Power flat over 6000rpm, 85mph in 5th

TheCafeKid
I've been meaning to sync the carbs, finally did it. Big improvement! Power climbs as it should, with a slight ledge at 6000. There may be more power in the engine yet, I haven't really fine tuned the carbs.
Thanks!

Well sir, congrats! One other thing that will do away with that little ledge you speak of that i JUST did on my 1100G. Shim the needles in the carbs. Get rid of the stock upper spacer on them, find some washers that are about the same size or smaller, but big enough ID to get the needle thru. I used ONE washer on mine. Prolly should use two, as now, when sitting for a long time in the midrange, and then ripping on the throttle, the bike JUMPS (and i mean LITTERALLY jumps) from say about 55 to 65 nearly instantly. It feels great, but its hard on the secondary gears and drive shaft. I think im just a tad rich, and one more washer would likely smooth it out a bit. But now, the bike PULLS and PULLS way past the limit of the speedo (on my bike, it stops at 85) Im sure on my trip back from KY today i was well over 100mph in some sections, and it didnt stop pulling. My mileage suffered a lil bit with the one washer too. I went from about 38-40 mpg avg on the highway, to 37mpg. Darn. LOL

[Buffalo Bill]

You called it right!

try getting the carbs synced on the bike. You may be suprised what a difference that makes.

[/quote]
TheCafeKid
I've been meaning to sync the carbs, finally did it. Big improvement! Power climbs as it should, with a slight ledge at 6000. There may be more power in the engine yet, I haven't really fine tuned the carbs.
Thanks!

I had a similar problem with my 850. Mine was rich and not lean. Try taking it for a rip with the air cleaner out. I was having a lack of air problem. Lots of power around town but as soon as I hit the highway, bog. Food for thought anyway. Also my mufflers were old and had a lack of flow. I went to a 4-1 megaphone and the one piece K&N and I have a new bike. I think I need to go up one size on the mains now but I am getting 46 miles/imperial gallon so I think it running pretty close.
Later,
Jason

[Buffalo Bill]

Carbs tuned to spec.

"Some CV carbed bikes are very lean from the factory and are very susceptible to any air leaks. Look for air leaks around the airbox."-tkent02

There was no sealing left around the airbox end doors, so I used weather seal foam, 1/4". The doors seemed to go on easier than I would like, I may have to increase the thickness of the weather seal.
Not road tested tested yet. It seems that this may do very little for my performance problem.
A carb sync test with vacuum gages shows #2 cylinder a little lower than the group. I will adjust that as soon as: well soon.
It may be that I will have to put larger main jets in. A stage 1 kit has a list price of $125. yet the list price for a 1982 stock jet is $5.50. There are no dimensions shown for the stock jets. Do you have info on the stock jets per year?
Thanks-Bill

[earlfor]

The first thing I would do is check compression and then check valve clearances.

Earl

Are you by chance using a K&N filter?

Like everyone said, professionals make mistakes too and dont take the time you would doing it yourself.

Anyone read Zen and the Art of Motorcycle Maintenance? This thread reminds me of that book and the author's problems with motorcycle shops. If I remember correctly, he blamed it on the kind of music the mechanics were listening to.

Getting back on track. when I bought my 1100G (about 20 years ago) it was only running on 3 and at the time I still thought it had a lot of power! But about 10 years ago, I had a stator go bad and it wasn't charging properly so it wasn't getting enough juice to the plugs and had symptoms similar to yours. Especially under a heavy load. Replaced the stator and the power came back, like getting shot out of a friggin cannon!

Im not one of the experts here but really sounds like you need to pull the carbs out and take a good look at them. Check that the bowls are all set to specs, make sure nothing is loose or broken inside.

My bike acted the same way after my first round of cleaning the carbs, one of the main jets was really rusted up and once i took it for a test drive must have broke off. Basically I was running on 3 cycls and it ran but near full throttle to go 65 on the highway. Seeing mine is a 650 that could related to your issue at 80s on the bigger engine.

Like everyone said, professionals make mistakes too and dont take the time you would doing it yourself.

Why not do it right, raise the needles, up the mains?
Tweak it to perfection??

Its a completely stock bike, and i may just raise the needles a touch based on some info ive garnered from here. Its likely a tad lean because the stock pipes are starting to leak around the Y connectors and the crossover. I plan a 4into1 and pods for it as soon as i find a set of 34's to rejet. (I wont rejet and drill these, want to keep them stock in case i want to make the bike stock again) And the plugs show just the SLIGHTEST hint of lean.

[tkent02]

Indeed. Plugs say so as well. I will play a touch with the screws this weekend.

Why not do it right, raise the needles, up the mains?
Tweak it to perfection??

You're lean too.

Indeed. Plugs say so as well. I will play a touch with the screws this weekend.

[tkent02]

My 1100G has a *lil* flat spot tween 4.25 and 5k. Not completely fall on its face flat, but enough to notice. But when it hits 5k, you better hold on tight, cos its like liftoff! It almost feels like a turbo spooling up to RPM. Its got a slight lag, then BOOM!

You're lean too.

My 1100G has a *lil* flat spot tween 4.25 and 5k. Not completely fall on its face flat, but enough to notice. But when it hits 5k, you better hold on tight, cos its like liftoff! It almost feels like a turbo spooling up to RPM. Its got a slight lag, then BOOM!

ah so..... hmmm mabey i need my hoodoo chicken foot then lol seriously though thanks that does make sense. i just ordered a new head pipe jet kit and k&n pod set up for the thing all of which were on backorder but hopefully ill be able to tune this sucker a bit better after i redo all that. lets see that will work out to about the 600th time ive pulled those carbs this year.

[tkent02]

not to hijack a thread here but im having a very similar problem i was hoping someone had a sugestion where to start adjusting at. mine runs great any throtle position from idle to around 4.5k and from about 6k and up. in between those ranges however it stumbles horribly like its running out of gas but only in that range. i do currently have it tuned a bit lean due to my jet kits not coming in yet but why only in that range?

Magic?
Actually it probably just happens to suck in a little less air at that RPM, and so not pulling in the fuel it needs to run correctly??
Once it gets reved up into the powerband it is pulling in more air so it can pull in enough fuel?
And below 4,500 it probably isn't pulling in much air at all so the pilot circuit can feed it enough fuel by itself to run OK?

Just guesses, the real answer is the magic.

But if you ever get it jetted correctly it will go a lot better I bet.

I had a Yamaha 650 twin once that did the same thing, just had a dead spot after putting on a new pipe.