GS850G - Fuel Upgrades

[vicimus]

Well, I got the carbs back on the bike last night and she actually starts! Imagine my surprise. I was half waiting for something to blow up.

It starts right up, but idles a bit poorly and at low speeds/rpm it stutters pretty badly. I took it out on the highway for a short bit and it was fine there at higher rpm. Is this just a carb sync issue? The air screw? The air screw is 4 1/2 turns out as suggested in the stage 3 kit instructions. The pilot jet is still stock.

Unfortunately it was after dark when I finally had everything put back together, so I wasn't able to tinker any more. I'm planning on hooking up the synchronizer tomorrow (since it's raining today.)

Any ideas? If I've got time, I'll check out the charging system as well.. some of those wires are a bit gummed up.

[TheCafeKid]

Well, I got the carbs back on the bike last night and she actually starts! Imagine my surprise. I was half waiting for something to blow up.

It starts right up, but idles a bit poorly and at low speeds/rpm it stutters pretty badly. I took it out on the highway for a short bit and it was fine there at higher rpm. Is this just a carb sync issue? The air screw? The air screw is 4 1/2 turns out as suggested in the stage 3 kit instructions. The pilot jet is still stock.

Unfortunately it was after dark when I finally had everything put back together, so I wasn't able to tinker any more. I'm planning on hooking up the synchronizer tomorrow (since it's raining today.)

Any ideas? If I've got time, I'll check out the charging system as well.. some of those wires are a bit gummed up.

4.5 turns out?????!!! Thats the top end of adjustment..somehow I dont think the good folks at DynoJet would suggest that. Are you sure its not 2.5 turns out?? And either way, those are baseline suggestions for getting it going. You still need to adjust the screws per the highest idle method. That is, set the idle at factory spec (1000-1200rpm or there-abouts) and then screw the #1 screw in, and back it out slowly till you hear the idle rise to its highest point. Stop there, back it back in a 1/8 turn, and readjust the idle, and on to the next carb, repeat for the remaining. They wont all be the same likely, especially if you havent used vac gauges or merc sticks to dynamic sync. (which I would suggest, but if you've never done it, it can be a chore on the CV carbs. Best to have someone who's experienced lend a hand) And even if you HAVE synced, they still will likely not be the same turns in or out.

Glad its running though, but I think your pee-poor idle will have something to do with being very rich on the pilot. Might take a look at your plugs...

[vicimus]

Ha! Weird. Check out the instructions here:

http://www.thegsresources.com/_forum/showthread.php?t=157035

My kit did not include that first sheet, and at the bottom of the last sheet it states "4-1/2 turns" .. even though that first says 2 1/2 turns. I'll have to turn them back in again and try that.

I did a sync on them last year with vacuum gauges. I'm intending to do that again as soon as I can. I've no idea where I found the information originally (possibly this forum), but I'm going to aim for 11.25inHg on #1&4 and 10inHg on #2&3.

[Octain]

4.5 turns out?????!!!..

Yup!
Mine are between 4-5 turns per DJ instructions.
Actually DJ says 5..

[vicimus]

Well, the way it's currently set up.. 165 main jets.. larger holes in the slides.. corrected air jets and the air screws 4.5 turns out, here's what I get with the plugs:



Completely black.. I'm assuming that's coming from an overly rich pilot circuit, and that's why it stutters at lower rpm? Is that just an air screw issue?

I changed the air screws to 2.5 turns out and it seemed to idle a bit better. Unfortunately I wasn't able to take it out for a test ride yet.

[gs road racer]

THOSE ARE NOT PHILLIPS but JIS you need different tools to work on japanese fastners Phillips is a DIN standard...there's a thread and some posts around here somewhere......as for the brass jets small electricians screwdrivers work best....

[Octain]

Well, the way it's currently set up.. 165 main jets.. larger holes in the slides.. corrected air jets and the air screws 4.5 turns out, here's what I get with the plugs

Completely black.. I'm assuming that's coming from an overly rich pilot circuit, and that's why it stutters at lower rpm? Is that just an air screw issue?

I changed the air screws to 2.5 turns out and it seemed to idle a bit better. Unfortunately I wasn't able to take it out for a test ride yet.

How did ya end up with this project.