Stage one 82 GS1100E flat spot 5500 to 7500rpm

[Anonymous]

Many years ago when I thought that a stock 82 GS1100EZ was just not fast enough(?) I went and added a Yosh exhaust, K&N filter in stock box and replaced the jets and needles in the carburators. The bike has never run well since. I did get some improvement from raising the needles but where my question is what jets works best to improve the flat spot range of 5500 to 7500. I suspect I have too small a main jet and need to get a new larger set installed. There must be a number of other members out there that run a similar setup. I don't know what jets I am running now. and I can't remeber if its a stage one or 3 installed, I think its a one with the factory air box?

Can anyone give me a recomendation on the rite main jet size to help me get this irritating flat spot fixed. It starts to splutter at 75+ in 5th gear and that really is annoying on road trips where I want to sit at 70 to 80 for a couple hours at a time.

 

[Joe Nardy]

The main jet is for full throttle running. Partial throttle running is controlled mainly by the needle. I would try raising the needles more. I'm not sure about Stage 1 but most of us running Stage 3 with PODs and pipes end up with the needles raised to or near the highest position. Read through this thread, it should help: http://www.thegsresources.com/_forum/viewtopic.php?t=30146

Let us know if this helps,
Joe

 

[RJ]

You need to go to a Stage III kit. I have the same setup on my '82 1100E. The individual pods flow too much air for Stage I. I had the same problem with my bike until I went to a Stage III. Wow, what a difference. The thing runs like a scalded ape without any kind of carburetion issues. My needles are on the second to lowest position. Do this and you'll never regret your mods again.

 

[RJ]

Clarification: needles with e clip on the second to lowest slot, which raises the needle up to the second to highest position.

 

[pano]

Shortly after I got my 82GS110E in 1984 I put a Yosh pipe on it and had it jetted at a local Suzuki shop. They put a 122.5 main jet in and had me remove my airbox cover.

When I switched to pods in the last couple of years and put in the dynajet needles in I am sure I had the stock needles in.

With the original jetting the bike pulled hard in 1st, 2nd, and 3rd and less in higher gears. I never much tried to go top speed back then and was content with burn outs and wheelies. In 1995 I was cruising up to Laconia with a few other guys and noticed a drop in power in 5th gear WOT. It just would not go any faster.

I dynoed it there and sure enough my power began to drop off in 4th and even more in 5th gear. It could have been a problem that crept in slowly over the years or something I had never noticed. The bike did sit for several years 89-94 or so.

I have since put the pods on and it pulls much better in the high gears, the lower gears it may be the same or less I am not sure .

As far as the original stage 1 jetting I did not have any flat spots at all. It was smooth except for the loss of power I noticed years later. If anything it was running a touch on the leaner side, definately was not running rich.

 

[Joe Nardy]

You need to go to a Stage III kit. I have the same setup on my '82 1100E. The individual pods flow too much air for Stage I. I had the same problem with my bike until I went to a Stage III. Wow, what a difference. The thing runs like a scalded ape without any kind of carburetion issues. My needles are on the second to lowest position. Do this and you'll never regret your mods again.

RJ and all,

Check Coug's original post:

I went and added a Yosh exhaust, K&N filter in stock box and replaced the jets and needles in the carburators.

If you are using the stock airbox with stock or K&N filter you still use Stage 1. Here's a cut & paste from the instructions for the Dynojet Kit:

1980-86 Suzuki GS1100-1150 16-valve
Stage 1&3
STAGE 1
For mildly tuned machines using the stock airbox, with stock or
K&N filter #N/A
STAGE 3
For mildly tuned machines using individual filters or velocity
stacks. K&N filters #RU-2922
Both stages may be used with a good aftermarket exhaust

Here's a link to the instructions:
http://www.dynojet.com/pdf/3133.pdf

Also, to clarify needle/clip position: RJ's description is correct. When I mentioned in my earlier post the highest position I meant the highest NEEDLE position, which is the lowest CLIP position. Sorry for any confusion.

Joe

 

[pano]

I guess the bottom line with my previous post is I had a similar set-up for years. I had 122.5 mains and as far as I could tell stock needles that I don't think are adjustable. Air box cover off.

I think you were at least curious about the size of the mains in a similar set up.

I had no sputtering but I eventually had power loss in 4th and 5th.

 

[RJ]

Yeah, nothing like actually paying attention to what you read! Sorry about that. I have to say that I never did run the stock air box so I can't really be sure what is going on. I will say that running individual pods seems to be the way to go, seeing as how much more air they flow compared to the stock box. Not to mention how much easier it is to perform maintenence.

 

[Anonymous]

I like the fast responses. I just bought " Mikuni 34mm carbs, 82-3 Katana GS1100, GS 1100 SD" and I will also buy a 4 main jet kit. I am going to first swap the whole carb set up and that should get me the stock power curve, except for the filter and exhaust mods.
I will then play with the main jets on my stage one carbs.
I have already played with the needles at first it almost was unusable since the needles were too low and then I tinkered with them to get the right setting( off the top of my head about 3 or 4 up from bottom.
Once I raised it too high it ran poorly again. I think I will enlarge the main jet see ebay http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=4520853655 they have 100, 110 , 120 ,140 mains not sure if this sizing is universally understood?

any recomendations on which I should use to test with the stage one setup?

Thanks Joe Nardy that is exactly what I did to my carbs. It is great to have that info again. I modified them at least 15 years ago and had forgotten.

 

[Rico]

Hey Coug et al,
I too bought a set of those mains for my 78 1000e (trying to save a buck)
I know in the end I'll be kicking myself in the ars for not just going with a K&N jet kit.
ANYWAY, as soon as my sync. tool gets here I'll be ripping into mine, so keep us informed on your progress. (good and bad)

Rico

 

[pano]

Keep in mind a Mikuni jet and Dynojet jet having the same # do not have the same size oriface. I had a comparison chart but can't seem to locate it now.

 

[KEITH KRAUSE]

Shortly after I got my 82GS110E in 1984 I put a Yosh pipe on it and had it jetted at a local Suzuki shop. They put a 122.5 main jet in and had me remove my airbox cover.

Just more proof you can't even trust the Suzuki dealer to know what to do.
Taking the cover off really leans it out. With no needle circuit changes, you were running lean at anything below 3/4 throttle position. The mixture screws would need richening too. Not sure about their main jet choice either. It would depend on what the stockers were. At least that's water under the bridge now.

 

[RJ]

I'd be careful about mixing manufacturers of jets and needles. The K&N and Dynojet components are designed to work together. If you ever get a chance to compare the needles from stock Mikunis to the others you'll see what I mean. Who's Stage I kit are you using? The only ones I'm aware of are K&N and Dynojet. I think they may even be made by the same manufacturer. You say you just bought a set of Mikuni 34's. Weren't you running these carbs originally? If not, start over again with the 34's and you shouldn't have a problem (don't forget to clean and synch). Good luck.

 

[Anonymous]

I love this board and the free help, I like to avoid the $60 an hour kind at the local shop. Anyway you bring up an interesting point If the jets I bought are for stock needles then they will probably not mate well with the Dynojet needles. It may be I wasted the money on the jets? The Dynojet has a tapered needle vs the stock pole needles. I do have another set of stock jets and needles so I will compare the union of both. I don't have carb balancers I will look and see if Ebay has a set. I don't see a listing on the Dynojet site for just main jets.

Ian

 

[RacingJake]

If it was me I'd check fuel flow first from the petcock, should flow like water from a garden hose then I'd spend 8 bucks for some real Mikuni 140 jets.

 

[pano]

I called up Dynojet and ordered a set of new main jets before so just call them. They have always been happy to help me.

http://www.dynojet.com/jetkits/suzukijets.shtml

If you schroll down to the 16vlv gs1100 there is a pdf that has the instructions and dynojet parts list. You could look at that to figure out what mains you should get for your application.

 

[Mr. Jiggles]

Did you synch the carbs after installing the kit?? I have a similar setup on my bike - aftermarket exhaust, stock air filter (no pods) Stage one and it runs pretty well.

What do your plugs look like?

 

[Joe Nardy]

Keep in mind a Mikuni jet and Dynojet jet having the same # do not have the same size oriface. I had a comparison chart but can't seem to locate it now.

Here's a comparison chart from a V-Max forum:

Mikuni/Dynojet Comparison

Joe

 

[Anonymous]

Jeff Tate sent me a great carb tuning site that breaks everything down. http://hometown.aol.com/ffastcbr/factorycarbtune.htm

I am first going to replace my main jets with 140's. After that once I see how it runs I will look at the needles. Once I get it running with no dramatic flat spots then to finish off I will see if a buddy or my local dealer can synch the carbs. Since I will have both a stock set and a stage 1 set I will hopefully have both synched. At the same time. I am hoping I can test without any air filter to test and synch. I will clean the area around in the hopes it won't suck dust and rocks into the engine during warmup, synching and test drives.

Ian

 

[pano]

I think Mikuni 140's may be too big.

When I put the individual pods on mine I used the dynojet 138's that came with the kit. Not knowing at the time that Mikuni and Dynojet had different flow rates for the same numbered sizes I put in some Mikuni 140's to try out. The Mikuni 140 is like a dynojet 149.3. When it got hotter in the summer and I was on a mountain ride I was deffinately running too rich. Rich enough where I lost power. Of course the air was thinner up there but I have since dropped back to the dynojet 138's. And again I have the K&N pod filters.