recommedation for GS1100 jetting

[Guest]

Before I tear down these carbs I was wondering what size main, needle, and idle jets I should order. I've decided to replace all of them since I've read that they can wear and I don't want to fight "bad" jets when doing the final adjustments. I have a GS1100GKE (1984) with a MAC 4 to 1 pipe and stock air filter.

[doctorgonzo]

Doubt they need to be replaced, but you'll almost have to get in there and look because if it's been jetted for the pipe, it won't have the stock size jets in it.

[d_hoffman]

I've looked at the mains and they are 115s. I'm 99% sure the PO did not rejet the carbs after he put on the MAC. He kept pretty good notes about whatever he did to the bike and I don't see a note about rejetting. I've read that the MAC doesn't "flow" as much as other after market pipes. So maybe the 115s would be ok. However, I've also read that these bikes came jetted lean from the factory so I'm just wondering what other GS (GS1100) owners have done and what has worked for them. In the meantime I'm continuing to read all the threads I can about cleaning/rebuilding carbs. I just want to have all the parts ordered before I start cleaning the carbs. In the meantime I'm still waiting on some shims from Z1 and now I found out that the tank really should be resealed because it's rusty.....
Oh well something else to do before I install the new petcock.

[lee1rbc]

I have the same bike and exhaust, running the stock air filter. I pulled out the 115s and installed 125s and that seems to be perfect jet (note: I am in Florida 1 mile from the ocean) You need to account for altitude. If I was at 1,000ft altitude I would run a 122.5 2,000ft a 120 main jet. I have not adjusted my needles and there is a small flat spot 5k when the bike is warming up.

[d_hoffman]

thanks. Here in Iowa we are at 750 ft. So maybe a 122.5 is the way to go. I remember a thread that talked about going to a 120 and the bike in question ran much cooler. Mine seemed to be way too hot also. I know an air cooled bike will be warm, and I haven't put very many miles on it, - but you should be able to keep your legs on the pegs and not feel like they are being burned. Have you adjusted your needle jet? I mean have you changed your clip height by adding/subtracting washers? (I need to reread those posts to get that correct) and what about your idle (pilot) jet? Did you leave it stock?

[d_hoffman]

oops I see you said you didn't adjust your needle. Thanks again for the advice.

[Mercaholic]

I spent some time on my '83 GS1100E with jetting and am satisfied with 130's for my pipe and pods set up.

With a MAC you should not need to update from the factory versions

[TheCafeKid]

I spent some time on my '83 GS1100E with jetting and am satisfied with 130's for my pipe and pods set up.

With a MAC you should not need to update from the factory versions

NOT true. They just like to throw that in thier advertisement to intice those that might be warry of swapping pipes due to the jetting involved. Anything but the stock Suzuki set up is going to create a variation in the back pressure the bike was jetted from the factory for. Couple this with the fact that these bikes came from the factory LEAN, and you will simply compound the situation. 115s ARE stock for the 1100G motor, and, you would be BEST SERVED to simply buy the DynoJet kit that IS AVAILABLE for your bike. They have already done the math and work for you. You simply have to install the kit as per the instructions they give you, and then do some final adjustments from there.

[d_hoffman]

thanks guys.
I'm guessing you mean DynoJet kit #1. Because the bike only has pipes added and not any modifications to air intake. I just don't like the idea of drilling out the slide assembly. Does that really have to be done? I would guess not. especially with a #1 kit.