Carb OEM specs as per factory manuals

[endlessGSgeek]

BS34 for 81 GS1100G

I'd like to know what the stock GS1100G settings are (were, that is). George Lesho rebuilt my BS34 rack (after three months and sent me someone else's BS32 for a GS850G!). I was told he was a real professional, but he didn't even send a single piece of documentaion back with them. I expected notes on the rebuild, and at the ver least, a jetting report. I did pay the extra $28 for rejetting. I synchronized them and borrowed my buddy's colortune for airscrew adjustment, but I sure would like to know what was in there, and what is in there NOW!!

Anybody have 81GS1100G jetting info (OEM)??

[endlessGSgeek]

factory manual??

Bass Clef.. Where the heck did that info come from ? It looks like a table out of a factory manual.

[BassCliff]

Bass Clef.. Where the heck did that info come from ? It looks like a table out of a factory manual.

Mr. endlessGSgeek,

I have a manual in pdf format. I have a couple others in hard copy that I can scan when necessary. Sometimes it's easier to copy/paste/upload/post the specific information when a picture is worth a thousand words. I hope I'm not violating copyright when posting little bits like that.

Thank you for your indulgence,

BassCliff

[endlessGSgeek]

pilot AND needle height shim for low end rescue

Mr. endlessGSgeek,

I have a manual in pdf format. I have a couple others in hard copy that I can scan when necessary. Sometimes it's easier to copy/paste/upload/post the specific information when a picture is worth a thousand words. I hope I'm not violating copyright when posting little bits like that.

BassCliff

I am sure you have nothing to worry about BaseCliff.

Lots of very useful tips in this thread. Thanks to all. The BS34 and smaller BS series Mikunis are good performers, but I have heard lots of nightmares about getting the low rpm range to behave. It is a high performance engine, and has to have intake valves (in particular) opening at the right time (clearance), need to be synchronized, need to have the right pilot jet to start with if you want it to behave when it isn't making much power. This is because power output needs to be balanced across the four cylinders. If two or three cylinders are not working as hard as others at low rpm because of jetting or synchronizing, YOU NOTICE IT!

I recently got a Morgantune (CarbtunePro) and synchronized my 1982 GS1100G. I have pod filters and a low restriction dual exhaust system (4into 2). George Lesho upped the main jet to a 150, and it DOES launch willingly above 4500rpm when it is warmed up (Jeez). Anyway, MUCH better after synchronizing, but still cold blooded as heck! Coughs and sputters below 2500 rpm, and even shows signs of being to lean when gently cruising at 3-4000rpm. I tried a Colortune, but it didn't fire near idle (not really a spark plug), so I could only guess on the airjets. I think I need to install one size higher, and maybe lift the needle by one ring.

Am I on the right track? Getting the needle to lift slightly soone may solve it, but It is SOOO cold blooded, it really seems to need a bigger pilot jet. Full choke, even when it is warm. High end performance is good though (main jet OK). I think it needs both needle shim (maybe one ring) and bigger pilot jet, because it won't idle and needs FULL choke when it shouldn't (pilot jet symptoms) and coughs and sputters at modest speeds cruising (needle not high enough). Can any body advise me on this??

I am really getting desparate

[BassCliff]

Hi Mr. endlessGSgeek,

I'm really sorry but I haven't learned the finer points of carb tweaking. This is something that is probably better posted in your own "technical repair" thread rather than sticking it here in this "carb spec info" thread. It might get a little more attention. I wish you all the best.

Thank you for your indulgence,

BassCliff

[first timer]

I don't mind you guys linking pictures but am a little concerned when the link goes down say a year from now then the info is lost again, so please type in the info so we have it forever. Also you guys are doing a great job restraining your selfs from asking to many technical questions here and clutering it up, I can't belive how well this has grown. One more thing then I'll step off my soap box, don't forget to go through all the posts or try searching in this tread for a specific model first then ask if you can't find it.

[first timer]

VM 29's (Smooth Bore) - 1978 GS1000 1979 stock motor, K&N RC-2450 filter, Yoshimura 4 into 1 header and can

This is what I am currently running (it maybe differant for others)

117.5 mains (what came with bike)
.9 air jet didn't pull it to check
#20 pilot jet (changed from #25, to rich for me with #25's)
5dl31-3 needle
0.6 needle jet
1.5 throttle valve (cut away)
1/2 turn out on the mix screw

Looking at Sudco's spec sheet these carbs i have (A7) look like they were set up for a kz650, kz900 or a kz1000

sudco recomends for the GS750/GS1000 (A12)
#115 mains
.9 air jet
#25 pilot jet
5dl31-3 needle
0.6 needle jet
2.0 throttle valve (cut away)

sudco recomends for the kz650, kz900 or a kz1000 (A7)
117.5 mains
.9 air jet didn't pull it to check
#25 pilot jet
5dl31-3 needle
0.6 needle jet
1.5 throttle valve (cut away)

sudco recomends for the cb750 thru '78 (A2)
115 mains
.9 air jet didn't pull it to check
#17.5 pilot jet
5dl31-3 needle
0.6 needle jet
1.5 throttle valve (cut away)

About my carbs the 117.5 mains came with them, the carbs were mounted on the bike and at some point before me the bike liked the setup. i heared stories of the bike pulling wheelies down the street back in the day from a shop owner who knew the bike. I cleaned up every thing, carbs were nasty and tried running it with the #25 pilot jets but was to rich and not happy, what i found out was the 1.5 throttle valves cause a richer condition then the 2.0 which is what the bike is suppost to have so by dropping the pilot jet down one it should step everything down one notch. Which it did and the bike has been running good since, but keep in mind i think my motor is starting to get tierd so a fresh motor might like the #25 pilot with a 1.5 throttle valve.

make sure you have everything cleaned out real good, there is a little hole under the throttel valve as well as a paper gasket under it too. Make sure the hole is clean and the the gasket is replaced or in good shape. Also check your needles my orginal ones were less then desireable. Also make sure you have new o-rings, you can get almost any size you can think of from mc-mastercarr.

download this pic and save it, it is a real good referance point

http://www.sudco.com/Diagrams323728/expvm29.gif

-Ryan

[uscwks]

MIkuni 34MM

Does anyone have the specs on the 82 1100E? I could sure use them. Would it be about the same as the 1100? Mainly need the float level.

[BassCliff]

Good point

I don't mind you guys linking pictures but am a little concerned when the link goes down say a year from now then the info is lost ...

Mr. uscwks,

That is a legitimate concern. When I find information in that format that I want to keep, I will right-click and "save image as" and keep my own copy on my own hard drive. But I will endeavor to post the text in the future.

Thank you for your indulgence,

BassCliff

[johnnay]

Ok, I read this thread and for some strange reason felt compelled to put all this info into an excel spreadsheet - like I don't get enough of those at work...:shock:

anyways, I have it completed with most of the info presented in this thread - there were a couple of posts that weren't in the same format or that were missing too much info, so I didn't include them.

It appears the forum won't let me upload it, so you'll have to email me if you want it (or if you want to tell me how/where to upload it). I'm going to bed now.. 8-[

[rrichard]

Hi Guys

I have been trying to buy a part for my GS1000En (1979), I though it was a needle valve or jet but when I ordered it, what arrived was not what I was looking for, I have searched the blown up drawings for this and still can not find it. The Carb is a VM26ss, it screws up into the carb body from underneath the bowl (the bowl does not need to be removed to get to it), it is brass and has a needle like appearance on a screw body . Any help much apreciated

Cheers

Richard
Dubai

[DonL]

GS1000G BS34SS VM34 specs
Here are the specs for stock jetting.
Specs in mm.
Carb Type- Mikuni BS34SS
Bore Size-34 mm
ID# - 49160
Idle r/min - 1050 +/- 100 r/min
Fuel Level - 5.0 +/- 0.5
Float Height - 22.4 +/- 1.0
Main Jet - #115
Main Air Jet - 1.7
Jet Needle - 5D57-3rd
Needle Jet - X-8
Pilot Jet - #40
Bypass - 0.9, 0.8, 0.8
Pilot Outlet - 0.7
Valve Seat - 2.0
Starter Jet - #45
Pilot Screw -Pre-Set (I started with 1-3/4 going to 2 or 3 out)
Pilot air jet - #160
Throttle Cable Play - 0.5-1.0
Choke Cable Play - 0.5-1.0

[haga41cat]

Help Me!

Hey guys does anyone have any carb settings for a 1984-85 GSX750ES.

Infact any info on that bike would be great i can't find anything cheers everyone!

[Suzuki_Don]

[quote=rrichard;696948]Hi Guys

Richard it looks like the pilot fuel screw to me.

Cheers

Don

[Zuriick]

I keep seeing questions about clip settings. I just rebuilt my carbs and the kit came with clips, but I never once saw a place where they should go. I have a 77 gs750. Can someone post a picture or be specific where this goes?