Suzuki GSX-R Motorcycle Forums Gixxer.com banner

1 - 20 of 21 Posts

·
Registered
Joined
·
178 Posts
Discussion Starter #1
hey everyone, just wanted to know your opinions of what carburators i should get, 38 rs mikunis, or 39 fcr keihins? i really don't know much about the keihins, but everyone i know runs mikunis. thanks for your input!
 
G

·
Guest
Joined
·
0 Posts
Most people that I know that have Oil Cooled Gixxers do run Mikuni's but not because they make more power but because they are cheaper by a few hundred dollars. From a horsepower aspect I believe the Keihins are better.... but thats my opinion.
 

·
Registered
Joined
·
1,014 Posts
I personally like the mikunis. They are cheaper and I have heard that they are easier to tune than the keihins. I guess its mostly your preferance.
 

·
Premium Member
Joined
·
372 Posts
Mikuni flat slides make one hell racket, sounds like the valves are out of lash, the keihins are much quieter.
 

·
Registered
Joined
·
129 Posts
Originally posted by cide:
hey everyone, just wanted to know your opinions of what carburators i should get, 38 rs mikunis, or 39 fcr keihins? i really don't know much about the keihins, but everyone i know runs mikunis. thanks for your input!
<font size="2" face="Verdana, Arial">From the research that I have done in the last few weeks the Keihins are better for power and they are smoother in operation. They also cost more. I was going to get the 38 mikuni's because of cost.

If you do get some carbs let me know as I might want to buy your 36's with the stage 3 kit. I have a set of stage three filters for the 38 flatslide mikuni's for sale/trade if you go that route. My bike has junk California carbs with no jet kit..

CT
 

·
Premium Member
Joined
·
838 Posts
Keihins all the way for max power. I run 36 mikunis on mine
I'm cheap

They seam to be just fine on my 1216. I have to pick up my bike from the dyno shop this week.
It just made 164 at the wheel to day on motor. I can't wait to spray it.
 

·
Registered
Joined
·
219 Posts
If these are for your '91 1100, one thing you should know before buying either set is that you need the "side-draft" or "horizontal-draft", NOT the "down-draft". You should also get a push/pull throttle for them too.
I'm running Mikuni RS's, and they're great, though they are loud.
I have never heard of any performance difference between the two (except that you can get Keihins 1mm bigger). They are both mechanical-flatslide-smoothbore and both have accelerator pumps.
They are both very tunable, yet not hard to tune (I think they're easier than CV's). I think that what makes the Keihin FCR's nicer is that they have rollers on the slides. I might be way off on this, but I don't think they are there to make them open smoother. I think that they are there so the slides don't rattle so much (quieter). But I'm no Guru.

[ 05-13-2002, 05:46 PM: Message edited by: 88/750 ]
 

·
Registered
Joined
·
978 Posts
if you want to spend 1000 dollars get the keihins

if you are on a buget you can get the mikuni from pingel for under 600

i run mikuni 40 couse i like the power and the sound
 

·
Banned
Joined
·
3,509 Posts
Originally posted by GSXR1255JIMMY:
if you want to spend 1000 dollars get the keihins

if you are on a buget you can get the mikuni from pingel for under 600

i run mikuni 40 couse i like the power and the sound
<font size="2" face="Verdana, Arial">There's the reasoning behind the 38mm's I with. I found the stock Mikuni's on ebay for a little over $200. Then another $130 for a jet kit. I could/should have just bought new Mikuni's for a little more...but I was trying to bring the motor project in under budget.
 

·
Registered
Joined
·
145 Posts
keihns make a little more power but they do not have the same drivability as mikunis mikunis are much smoother in the way of throotlle response
 

·
Registered
Joined
·
316 Posts
I run mikuni RS 40mm. A nice feature about them is the left side bell crank (optional). Tuning no longer requires removal of the gas tank. They must be ordered this way.

Somehow I was lucky enough to find a used set on dragbike.com.

I never ran keihin fcrs on my bikes but know guys who swear by them.

I'm happy with my mikunis.

-Dave
 

·
Registered
Joined
·
178 Posts
Discussion Starter #14
thanks everyone for answering. i think i may go with 38 rs mikunis. the cheapest place i have found is pingel. they are $565. i guess i better start pinching pennies!
 

·
Registered
Joined
·
763 Posts
Originally posted by cide:
thanks everyone for answering. i think i may go with 38 rs mikunis. the cheapest place i have found is pingel. they are $565. i guess i better start pinching pennies!
<font size="2" face="Verdana, Arial">Cide,

If you keep yours eyes open, you will be able to find a set on dragbike.com or ebay.com in no time. Or if you put a post out there or maybe even on here that you are looking for them, someone will have a set they are letting go and you can save some $$$'s that way....

Oil-cooled GSXR's 4-life.

JDB1371
 

·
Registered
Joined
·
2,491 Posts
I picked up a set of Keihin 41mm F-CR's for under 500, so they are out there, I have heard that the Keihins are the best and easier to set up than Mikuni's, I guess it comes down to personall preferance and what you plan to do to the motor, that and I couldn't pass up the price on the Keihins
-Karl
 

·
Registered
Joined
·
461 Posts
how would 41mm FCRs work on a stock 1052 motor?
I had some guy offer to sell me some 41s for $400CDN($260 US).
I do have 77mm cosworth pistons(12.1:1), and will be redoing the motor(installing pistons, fixing second gear, porting the head, doing a proper valve job, balancing motor, etc) this winter.
At that point I think the 41s would be okay, but until then, would these carbs be too much for a stock 1052 motor?
 

·
Premium Member
Joined
·
838 Posts
They would not be the best setup for a stock 1052.
I would take them for my bike
Can I buy them from him


Let me know.
 

·
Registered
Joined
·
221 Posts
I know that there will probably be 100 people to disagree with me but 41's are just to big for a 1052 or 1127 or even a 1216 unless it is really hot with big cams and lot's of head work.41's are for those 1300+cc motors 39's will be more than enough! although for the money I would buy the 41 and keep them around for sure. I also would be interested in buying them just to hang on my wall until i need them. A set of 38 mikunis will support all the flow a Gsxr need from modified 750's all the way to 1216's. THey are cheap easy to work on and well built. BUT LECTRONS ARE THE BEST FOR RACING! Just had to say that since that's what I run on my 86' So SIMPLE!
No jets to fool around with! Sync the carbs with the top adjuster and set the easily adj air screw(each carb has a thumb wheel!) Change jetting simply by raising or lowering the needles. It couldn't get any simpler. Of course they don't have an idle circuit so they can't be ridden(very far) on the street. Oh well you can't have everything!
 
1 - 20 of 21 Posts
Top