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Main Area => General GS500 Discussion => Topic started by: Rangerkyote on September 22, 2006, 06:28:35 PM

Title: 34 or 36mm carbs
Post by: Rangerkyote on September 22, 2006, 06:28:35 PM
Has anyone ever tried bigger carbs on the GS500?  I know there's at least 1 or 2 bikes out there that have a similar setup with twin mikuni 36mm carbs.  Wonder if it works.
Title: Re: 34 or 36mm carbs
Post by: The Buddha on September 22, 2006, 06:46:59 PM
Yes and the bike is capable of managing its heat so well and running such high compression and make so much power it will put a ducati to shame.
Honestly 34-36-38 carbs wont make any difference if you cant turn 13-15K revs and get rid of all that heat effectively.
Cool.
Srinath.
Title: Re: 34 or 36mm carbs
Post by: CirclesCenter on September 22, 2006, 09:16:54 PM
Srinath,

It seems like you've probed the depth of the GS's limits. I would like to ping a few questions off of you if you don't mind. (If you do then just be like :p )

632 cc comes from 79mm pistons and a stroker crank that I can't seem to find ANYTHING about.

I think I'd be pretty happy with 541 (78mm pistons) but that motor would want more cam and carb, am I right? How much?

How about forged rods/cranks/sleeves? I'm assuming the sleeves would be easy, but the rods and crank would be "fun"

Since I want to do rods, couldn't I just (in theory at least) find some with a bigger wrist pin to give me a larger assortment of piston options? Granted the rod profile might pose a clearance problem...

And I'm not dead set on a stroker crank, I just want a beefy crank to hold the extra power I want to make.

I fully understand that larger carbs on the stock motor aren't useful, but with the increased displacement would it be a good idea?

Anybody else who has something to add (experience, not speculation please.) would be welcomed.

(Yes I know I am throwing money into a sink-hole. I don't care, I don't want a 600cc super sport, I want a modified GS)

Title: Re: 34 or 36mm carbs
Post by: Rangerkyote on September 22, 2006, 10:35:12 PM
Actually, I was looking for something other than speculation.  Was hoping someone on here tried something different than a jet change.
Title: Re: 34 or 36mm carbs
Post by: Affschnozel on September 23, 2006, 07:57:11 AM
There was a guy around here that started swaping stuff from bigger bikes in the suzuki family and he ended up with GSXR600 :o
Title: Re: 34 or 36mm carbs
Post by: dgyver on September 23, 2006, 09:30:41 AM
Larger carbs are easy to do. Most do not since the initial cost is preventative. CV carbs will run $75-150 and mechanical's would be in the $200-400 range. Also, those that do have larger carbs are not concerned about gas mileage, especially with the mechanical slide carbs.

I now have 36mm CV carbs on my 541. It had 34mm round slides, which I regret selling. Early GSXR's used 36mm...88-92 something in that year range. They were side draft but in the mid 90's they changed to downdraft, so those will not work. Fairly easy to reduce a set of 4 down to 2. The Mikuni 33-36 are the same except for the bore diameter.

Larger carbs without some additional motor work will not provide much performance gain.
Title: Re: 34 or 36mm carbs
Post by: Rangerkyote on September 23, 2006, 09:18:54 PM
Thanks dgyver!  That's the type of info I was looking for.  I kinda figured the mikunis were all pretty much the same but didn't know because I haven't looked side byb side.  Now I just need to hunt down some good carbs on ebay or the scrapper.