36mm Mikuni Flatslides vs. Stock CV Carbs

[Mark M]

Just wondering what sort of difference I would see if I traded my stock CV's with pods for a set of 34mm or 36mm flatslides? Bike is an 82 1100E currently with pods and a Kerker 4-1 pipe, stock cams. It runs very well and I really have no complaints, but what sort of improvement would the flatslides be and where (more bottom end, top end, etc.)?

Thanks,
Mark

[posplayr]

I have a set of 36mm Flatslides CV's (Slingshot 1100 carbs)

that I will install on my GS1100ED. I also have a set on an 86 GSXR 1100. From what I can tell and have read the FS plungers respond much faster than the larger plain CV to throttle input and so expect more on off performance. If setup right the on-off should not be detrimental and still be very ridable.

Also there is an overall increase in HP as well. Just guessing from what I have read that it is noticeable increase so I'd figure 5 hp maybe (with pods,cams,4:1 and hot coils).

Forget who it was that said his 36mm FS equipped EZ/ED would walk away from any stock EZ/ED

Pos

[rapidray]

More midrange & top end. No loss of driveability when set up correctly. You also need to get a push/pull throttle assembly with cables. Top end power gain as much as 8-10 hp is what I've seen on the dyno. Ray.

[TheCafeKid]

Im still not sold on putting a larger throat carb on an otherwise stock bike (meaning cams, ignition timing, etc) You would surely have to DOWN jet from whatever those were set up for. 34mm Flatslides would make more sense to me, unless you were planning to upgrade the bore, cams, cam timing, on and on. The bike can only take so much gas at any given throttle position before fouling out. Bigger bored carbs dont seem to make much sense to me.

[blowerbike]

ray,
i beleive they are talking about GSXR style vaccum carbs(flat vaccum slides).
TCK,
vaccum carbs and mechanical carbs are not size for size.
to get a vaccum carb to flow like a 33mm smoothbore...
you have to go up 3mm on the vaccum carbs=36mm.
this is flow bench information that was shared with me years ago.
the topic starter here needs to clarifly (what)style of carbs he is asking information on.
(mechanical) or (vaccum)
MARRY X-MAS GS-ERS

[Mark M]

ray,
i beleive they are talking about GSXR style vaccum carbs(flat vaccum slides).

Nope, Ray has it right. I was talking about RS flatslides, not the flatslide CV type.

Mark

[blowerbike]

well then what is popslayer talking about
slingshots..
no one said anything differant so i went with it
OOOOOOOOOOPS!!!

[Mark M]

More midrange & top end. No loss of driveability when set up correctly. You also need to get a push/pull throttle assembly with cables. Top end power gain as much as 8-10 hp is what I've seen on the dyno. Ray.

Ray, is that 8-10hp more than properly jetted CV's on an otherwise stock 1100? Or with cams and other mods as well? $800 (or whatever they are now at APE) doesn't sound nearly as bad for 10hp more...

Where would I be with mild aftermarket cams (G3 maybe?), 36mm RS's and a 4-1 pipe? For reference, the bike made 102rwhp at nearly 4000ft with a modified airbox and the pipe, before I bought it. With the pods and degreed stock cams it now runs noticeably stronger than when I bought it, probably 104-105rwhp if I dynoed it again.

Mark

[rapidray]

With the carbs only you would see in the neighborhood of 110-112 or so but most of the BIG gain in power will be from 7500 up. Also, if you do cams with the 36s you will see even more power & sooner in the rpm range. I would use the Cam Motion G4s instead of G3s. Whatever you decide I am a dealer for Cam Motion & Web both and can get what you need if I don't already have them in stock. Merry Christmas! Ray.

[Mark M]

With the carbs only you would see in the neighborhood of 110-112 or so but most of the BIG gain in power will be from 7500 up. Also, if you do cams with the 36s you will see even more power & sooner in the rpm range. I would use the Cam Motion G4s instead of G3s. Whatever you decide I am a dealer for Cam Motion & Web both and can get what you need if I don't already have them in stock. Merry Christmas! Ray.

Thanks for the help, Ray. I am working on a new exhaust system from the collector back and will see what that gets me for power. If it performs well, then I will see if I think I need the carbs and cams or not. Maybe next winter if I get bored with it...

I will be in touch about the cams, either way.

Mark

[BlackStar]

I put a set of RS34's on my 1085. Runs real good, no comparison to stock since they were junk when I got the bike. What I really like about them is the ease of tuning. No more pulling the carbs or lost sync for a jet needle change.

[trippivot]

if you take the time and get them set up right..flatslides are manageable for street use. YES more power. NO on smoothness. the flatslides- are different with the throttle inputs and power delivery. I say more jerky on and off the power. they are racing carbs after all and the emphasis is half throttle to W.O.T. non smog legal the 34mm will out flow your head capacity (CFM). outflowing is not too bad but W.O.T> will never be necessary.

I still advise CV carbs for street use. they are smooth through pilot ~needle progression transition. making 35 mph and 45 mph easy to ride and maneuver in smoothly in traffic.
economy will be an issue too. CV's get the best gas mileage

Life is full of compromises get 1 thing give another. racing ~ street

[jwhelan65]

informative

Good information here, I have been considering making the leap to flatsides myself but can't decide if its worth it. My 82 GS1100 runs well but I would like to get a little more WOW out of her without the huge expense of tearing down the engine.

[posplayr]

Slingshot Carbs

Here is a links discussing 36mm Slingshot CV Flatslides (not RS Flatslides)

http://www.thegsresources.com/_forum/showthread.php?p=229518&highlight=slingshot+Flatslide#post229518

Merry Christmas all.

Pos

P.S Blackstar that Skunk looks great. Looks like you were putting it together just earlier this year. Very nice work.

[rapidray]

if you take the time and get them set up right..flatslides are manageable for street use. YES more power. NO on smoothness. the flatslides- are different with the throttle inputs and power delivery. I say more jerky on and off the power. they are racing carbs after all and the emphasis is half throttle to W.O.T. non smog legal the 34mm will out flow your head capacity (CFM). outflowing is not too bad but W.O.T> will never be necessary.

I still advise CV carbs for street use. they are smooth through pilot ~needle progression transition. making 35 mph and 45 mph easy to ride and maneuver in smoothly in traffic.
economy will be an issue too. CV's get the best gas mileage

Life is full of compromises get 1 thing give another. racing ~ street

The only thing I agree with you here Jeff is the fuel mileage. Yes, you need learn to be a little smoother with your throttle hand but that will only make you a better rider anyway. Merry Christmas everyone! Ray