40mm slingshot carbs on GSX1100??

[Crest of a wave]

I've got a set of 40mm carbs from a 1991 GSXR1100 slingshot, I know they will fit my GSX1100ET, but are they too big?? The engine has a Wiseco 1170 kit, but is 40mm just too much? (Is there such a thing as too much:)) I can see people are running 36 and 38mm, plus American websites suggest 40mm for track bikes only. I'm thinking maybe the inlets and valves are just not big enough, so I'd be wasting my time.

any thoughts? 

[Gixer1460]

Honestly 40's are too big for the 1100M / N and they are a bitch to set up. If you want to keep the torque monster feel of the GSX - go with 36mm CV's - 36mm RS flaties even better!

[Pd1987]

Agreed they are too big, they were too big really when they were made! As said about spot on advice or 38mm as they have the extra pump and are good for tuning 

[Crest of a wave]

Cheers guys, I'll hunt for some 36 or 38s

[minx]

36s are harder to find as they were fitted to fewer models therefore tend to fetch a higher premium. Even 38s are harder to come by.

Are you swapping out the originals?

[Pd1987]

It just so happens I actually have a set of 38's for sale, well about to be put on Eblag full working order. Only reason is I have knowledge on this through trial.... Fitted the 38's to a 750 and they are far too big!!! 

[KATANAMANGLER]

36s would work best on the 1170. 34s work and you would probably get away with 38s but 36s are optimum IMHO

[Crest of a wave]

I don't have a stock set of carbs, this is a complete project, with engine, running gear and frame all coming from different sources. So the world is my oyster for carbs, I just happen to have a set of 40mm, hence my question.

Were the 36s only fitted to GSXR750/1100? I've just had a quick look on Eblag and I can see sets of 38s, but no 36s

[dago]

i'm sure bandits had 36mm carbs as std so should be a few about .

Edited August 11, 2015 by dago

[kokolis]

Slingshot 750 88-90. 1100 89-90, bandit 1200 (late model has bsr 36 though)

[Captain Chaos]

Slingshot 750 '90 has 38mm carbs.

The BST36's are also on GSX1100G's, Teapot 750's, and some Triumphs from the '90s.

[Crest of a wave]

Cheers guys, that gives me more options. 36s it is, if I can find some.

[katman1168]

yes 36s much better

 

[Crest of a wave]

Thanks for the information about alternatives, just got myself a set of 36mm Triumph Daytona 1200 carbs, exactly the same Mikuni BST36 as GSXR.

anybody got any thoughts on where to start with jetting? I'm running an 1168 big bore with Harris pipe and plan to run pod filters. Is it just a matter of getting it to run and seeing what happens. If somebody has done this mod and can give me a baseline to start from it would be really useful.