Carb differences 1981 GS1100 vs 1983 GS1100

[Anonymous]

Does anyone know if the carburators on a 1981 GS1100 were the same model as the 1983 GS 1100 ?

[daveo]

1981 1100 EX

Specs in mm.
Carb Type- Mikuni BS34SS
Bore Size-34 mm
ID# - 49200
Idle r/min - 1050 +/- 100 r/min
Fuel Level - 5.0 +/- 0.5
Float Height - 22.4 +/- 1.0
Main Jet - #107.5
Main Air Jet - 1.2
Jet Needle - 5D58
Needle Jet - X-1
Pilot Jet - #45
Bypass - 0.8, 0.8, 0.8
Pilot Outlet - 0.9
Valve Seat - 2.0
Starter Jet - #32.5
Pilot Screw -Pre-Set, Varies
Throttle Cable Play - 0.5-1.0


1983 1100 ED/ESD

Specs in mm.
Carb Type- Mikuni BS34SS
Bore Size-34 mm
ID# - 49380
Idle r/min - 1050 +/- 100 r/min
Fuel Level - 5.0 +/- 0.5
Float Height - 22.4 +/- 1.0
Main Jet - #112.5
Main Air Jet - 1.2
Jet Needle - 5D58
Needle Jet - X-1
Pilot Jet - #45
Bypass - 0.8, 0.8, 0.8
Pilot Outlet - 1.0
Valve Seat - 2.0
Starter Jet - #32.5
Pilot Screw - Pre-Set, Varies
Pilot Air Jet - #180
Throttle Cable Play - 0.5-1.0

[Jethro]

Not to hyjack this post, but in these specs there are starter jets listed. What and where are these? Would pod filters (increased air flow) require these to be changed to a bigger size? My bike has a problem starting.

I thought I knew everything about my carbs, but apparently not.

Anyway, I have both those years 1100's and have had both carbs off and in 100 parts each. I am confident that the carbs could interchange. The specs above confirm this- with a few jetting changes.

[Anonymous]

Could your starting problem be due to a bad vacuum hose or diagphram in the fuel shut off?

Vic

[daveo]

Not to hyjack this post, but in these specs there are starter jets listed. What and where are these? Would pod filters (increased air flow) require these to be changed to a bigger size? My bike has a problem starting.

No prob, they're what feeds the choke circuit and are in the float bowl....Mine starts fine with pods,and I never changed those jets, If everything else is spot on and it's still hard starting, especially when cold, you may want to do a dry, then wet, compression test or leakdown test, I would suspect the rings. You're right as far as interchanging the sets goes...no problem, I ran the 34mm's on my 750, took a bit to get the jetting right, but it was a screamer when done

[Jethro]

Compression is great, 160-170 across the board. In the loat bowl I only know of the float needle jet, the main and the pilot. Is this starter jet removeable and/or replaceable? I've rebuilt my carbs at least 3 times, with good K&L carb rebuild kits and never have come accross these 4th jets called starter jets!

[daveo]

Compression is great, 160-170 across the board. In the loat bowl I only know of the float needle jet, the main and the pilot. Is this starter jet removeable and/or replaceable? I've rebuilt my carbs at least 3 times, with good K&L carb rebuild kits and never have come accross these 4th jets called starter jets!

you're right, with that kind of compression, rings ain't the problem...the starter jet doesn't look like the other jets, it looks like a brass pickup tube in the float bowl with a calibrated jet hole in the bottom,(trace the choke circuit, most of it runs externally on the carb body, begins in the float bowl) not easily changeable, but it could be drilled....