Fuel/Air Mixture...

[Anonymous]

I would like to know where on my 1100G carbs are the fuel/air mix screws.
Recently replaced the factory AIRBOX with independent air filters (4).
Made by UNIFILTER.
I need to adjust the mix because it's too lean.
Bogs down when I try to gun it.
I did not replace filters to beat on my bike, rather because putting the box back in was a royal pain. Too tight. I love my cherry 1100G and I baby it.
HELP!

[Bill + Karen]

You didn't mention a year but on my 82 1100G they are on top on the engine side of the carb. They are most likely still hidden under the U.S. approved plugs that prevent adjustment, these have to be drilled out in order to get to the pilot screws. You also might have to change the jets to bigger ones. Safe Riding, Bill

[Anonymous]

Re: Fuel/Air Mixture...

I would like to know where on my 1100G carbs are the fuel/air mix screws.
Recently replaced the factory AIRBOX with independent air filters (4).
Made by UNIFILTER.
I need to adjust the mix because it's too lean.
Bogs down when I try to gun it.
I did not replace filters to beat on my bike, rather because putting the box back in was a royal pain. Too tight. I love my cherry 1100G and I baby it.
HELP!

I dont think that adjusting your idle screws is the amswer--you usually have to take a plug reading and adjust your mid range jets-- Did you do the pod mod without first putting in a performance exhaust system
when does it bog down when you are trying to gun it--in neutral--when just cruising etc??

[Anonymous]

I think before you have it dailed in and running right you'll have changed every jet in the carb several times. I attemped this once on a '83 GS750ES and was very sorry for it. I never could get it to run well at every throttle position and RPM. I also may have done some damage to the engine by running lean. My advice is to try and find a jet kit made for this bike or put the air box back on. Or, at the very least, don't ride it till you talk to someone who has done the same thing to their GS1100G and knows exactly what jetting will work.
Good luck,
Axel

[Anonymous]

Just checked the Dennis Kirk web site for a jet kit. Don't know what year your bike is but they do show one for an '83. Cost about $115.00, made by Dyna. If you're keeping the filters this is money well spent. www.denniskirk.com
Axel

[Anonymous]

Just checked the Dennis Kirk web site for a jet kit. Don't know what year your bike is but they do show one for an '83. Cost about $115.00, made by Dyna. If you're keeping the filters this is money well spent. www.denniskirk.com
Axel

What about the exhaust Axel

[Anonymous]

Slowpoke,
Not sure of the question. But if you're asking about the effects a performance exhaust has on the jetting I would say not near as much as air box mods. Let's say you left the original airbox alone and put the exhaust on. You could probably get by with just raising the needle slightly and richening the air screws a bit, and maybe, just maybe, a slight change to the main jet (mains usually came rich from the factory on big bikes). The airbox is a different story. The airboxes on these older bikes were super restrictive. Just look at the newer sport bikes, their airboxes are about the three times the size and also have a much larger air inlets . When you remove the restrictive airbox on older bikes major jetting changes have to happen. You can even see this in the jet kits sold for new compared to older bikes. Jet kits for new bikes, where they keep the airbox, the jets are only slightly different than stock. On the older bikes, where they remove the box, they're radically different, much richer.
I've put a few diferent exhaust on my bikes and before rejetting they might pop a little but basically ran okay. But any change to the airbox like removing the lid or inlet snorkle will lean them out drastically. Case in point, I once bought an '82 GS1100E that ran so lean it wouldn't pull over 3,000 rpm. The owner thought it had serious engine problems. All it turned out to be was the hose between the front and rear airbox had come loose. Once I reconnected the hose it ran like new. It also had an aftermarket exhaust on it with stock jetting.
I hope this doesn't cause a flood of disagreements.
Axel

[Don Lobacz]

I agree with axel that exhaust changes will only need a small change in carburation (for my 79 GS1000 to run right with a Yoshimura race pipe, I needed to go up 1 on the main and raise the needle 1 clip as per Yoshimura). I disagree with him that the reason for a big change for airbox removal is due to air restriction. It is due to the CV carb design which requires vacuum differential to raise the slides. A modern sportbike will not run right if its airbox is yanked off either, but the effect may be less severe due to the specific vacuums in a larger airbox. I do not really like jet kits, but the one good point to them is that they come with softer (not stiffer, as most people believe) springs so that the weaker vacuum behind the carbs is more able to lift the slides. I have seen some 80s era bikes run great with K&Ns when their stock carbs had the mains raised 5 sizes, the needles raised with 1 shim each and the airfuel screw backed out 1/2 turn more. I have also seen a few that would not run well no matter how much you tinkered. The airfuel screw is on the top front of the carb, under an aluminum plug, but that won't help at all after an airbox removal (although it may help you foul plugs at idle, if that's what you want).

You say you don't like the airbox because it's too tight (?!). They may be a pain in the butt sometimes, but if you are careful and learn a few of the tricks, it's very straightforward. My question is: you shouldn't have to get in there for years if the carbs are clean and kept that way with filters and proper draining in winter. The best performance and reliability for your bike will come with the stock airbox and stock jetting, especially since you enjoy the 'cherry' aspect of your bike.

[Anonymous]

Don,
You're right. All my personal experience has been with CV carbs. and I understand they are very sensitive to the vacuum or back pressures created by the airbox, but doesn't the restriction and volume recreate the vacuum? I've also heard that the smooth bore type carbs require much less extensive re-jetting. I didn't get into it because I think we're talking about a bike with CV's. Further, I would keep the stock airbox too, it has several advantages that warrant it.
Still my main point is that if someone is intent on individual filters that their best bet is using a jet kit.
Axel