Suzuki GSX-R Motorcycle Forums Gixxer.com banner

38mm CV mikunis on 1127

3K views 14 replies 10 participants last post by  gsxr1216 
#1 ·
OK, so maybe my ebaying is getting a little bit outta hand... I just bought a set of 38mm "slingshot" carbs from a `90 750(or so the seller says - they look like it) has anyone else put these on an otherwise stock 1127 motor and how did it work out? I've got my 36mm's dialed-in pretty good with the dual filters (wasn't easy) and I don't wanna go spend a day fiddling around with it if it's not gonna change anything noticeable on the bike. For reference, I am making *p-l-e-n-t-y* of low down and mid-rpm torque and I don't mind giving a little up if it means I can see a big increase (5HP or more) on top. I see that factory-pro makes a jet-kit for doing this exact mod. Anyone used it? numbers, suggestions, anyone?
 
#2 ·
I have them on my 90 1127.........To be honest i havent had 36's on there, so i dont know the difference of the 2.

But.........I'm getting 40 flatslides, and will be done with it..........

Oldgixxer would be able to help more on this, since it was his bike!

With the 38's it carries my 295 lb ass pretty nice.....
 
#5 ·
Along the same lines of Fastcat's question:
What would be the best carb. mod to the 1127 motor with no major mods - (I.E. Dual K&N PODs V&H Supersport header)?
I have essentially the same setup and have been wondering what a set of XXmm Flatsides would do for an increase in power? (XX= 38, 40mm)?

Thanks!
 
#6 ·
Originally posted by bevan:
Along the same lines of Fastcat's question:
What would be the best carb. mod to the 1127 motor with no major mods - (I.E. Dual K&N PODs V&H Supersport header)?
I have essentially the same setup and have been wondering what a set of XXmm Flatsides would do for an increase in power? (XX= 38, 40mm)?

Thanks!
<font size="2" face="Verdana, Arial">Go with nothing bigger than 38 flatslides on a stock motor...
-Karl
 
#7 ·
O.K.-here's the scoop.The 38mm C.V's work alright but...you NEED the jet kit specifically for this conversion.And it ain't cheap either.I had to order it directly from Dynojet and it was $200.So,figure if you spend $100-150 on the carbs,plus the $200 for the kit,now your looking at $3-350.You can get a good used set of 36-38 RS faltslides for that price and you will be happier with the performance gains and they will be ALOT easier to tune.However,on the Flatslide's,you will need a push/pull throttle and the return springs on the flatslides are ALOT stronger(read VERY STIFF throttle) then the C.V.'s,some people never get used to it,so check that out first before you buy 'em. I also agree that for a STOCK engine,you will see no benefit from putting 40mm flatslide's on and will just see a decrease in mileage per gallon.
 
#8 ·
Rory, I've got a set of '92 750 38mm CV's... gonna need them for about another month (planning to run them for initial fire-up on a fresh Bandit engine which will then be turbocharged) but after that I will be looking to sell them.

Will drop you a line then; if you're still in the market we might work something out.

Ed
 
#9 ·
Fellas,

I have a set of used

1. 36 CV's off slingshot 750
2. 38mm CV's off of 1992 750/907
3. 34 mm CV's from an earlier 750, I assume 86-87 maybe????

2 sets of Mikuni Flatslides
a. 36 mm - set up for alcohol
B. 38 mm - set up for alcohol,

The flatslides just need the jets and the jet guides switched out for gas and they are good to go.

If anyone needs anything let me know..

Also have:
1. set of balanced, polished & shot peened 1127 rods available

2. an 1127 crank available soon too.

Thanks,

JDB1371
 
#11 ·
Originally posted by oldgixxer:
O.K.-here's the scoop.The 38mm C.V's work alright but...you NEED the jet kit specifically for this conversion.And it ain't cheap either.I had to order it directly from Dynojet and it was $200.So,figure if you spend $100-150 on the carbs,plus the $200 for the kit,now your looking at $3-350.You can get a good used set of 36-38 RS faltslides for that price and you will be happier with the performance gains and they will be ALOT easier to tune.However,on the Flatslide's,you will need a push/pull throttle and the return springs on the flatslides are ALOT stronger(read VERY STIFF throttle) then the C.V.'s,some people never get used to it,so check that out first before you buy 'em. I also agree that for a STOCK engine,you will see no benefit from putting 40mm flatslide's on and will just see a decrease in mileage per gallon.
<font size="2" face="Verdana, Arial">I already *got* the 38mm CV's (and I spent a lot less than $100 ...ain't ebay great?) and the factorypro site lists a kit to do this with for $119 ...I'll keep ya'all posted with how it goes... I already have dyno traces for the motor with the current 36mm setup so I'll be able to give a detailed report
wish me luck.
 
#13 ·
z1bigtom,

Unless you have big mods to your 1127 motor or plan on making big mods to the 1127 motor the 40mm flatslides, I feel, will be too big of a jump for th estock motro and you will only be puliing to the gas pump more often and may lose some HP from it.

36's or 38's would be a better selection.

I look at it like this, and this is jsut my 2 cents:

36 Flats flow like 38mm cv's

38 Flats flow like 40mm cv's (found on the Candian and overseas GSXR 1100's)

I just thing jumping from stock carbs all the way to 40's might be overkill, unless you plan on going 1277cc or 1340cc + in the near future...

Just me 2 cents....

Good Luck either way

JDB1371
 
#14 ·
GSXR1216,

As for the crank, The crank will be checked here before it Leave FLorida at a respectable place,
Tachyon racing and will be sent with the bill for that being done, to prove it useability. With teh crank numbers and letters on the bill matching the crank in the box going to you.

THAT IS THE ONLY WAY I SELL OR BUY CRANKS.

So the price for the crank would be $275.00

Bad cranks that don't pass but could be used to be welded up repaired and/or stroked are $65.00-80.00 + s/h depending on their shape.

The rods would be $100.00

Crank and rods packaged together you can get sent to you shipped for $400.00

JDB1371
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top