Description
These Mikuni RS38-D19-K RS carbs will breath a whole new lease of life into your machine with around a 25% increase in power, whilst making it perform and operate as it should.
You will very quickly realize that the expense of a rebuild of your old worn OEM carbs can far exceed the cost of these new units and also unfortunately as with many rebuilds now days you only have the option in many cases of gambling with very poor quality aftermarket parts. Considering this and if intending to ride and enjoy your motorcycle it makes good sense to retire your OEM carbs into the cupboard and step up to a set of RS’s.
Before rushing in and ordering please firstly check your carb spacing and carbie sizes for compatibility. These are not suited for downdraft engines.
This Mikuni RS kit comes with the following carb centre to centre spacings for direct fitment to GSX-R 750 to’90, GSX-R1100 to ’90, Suzuki GS 1000-1150 (not the F touring models), Kawasaki KZ 1000-1100
Check your carb spacing as per the picture and if not 77-93-77 as supplied here but only requiring a 77-85-77 spacing adjustment this can be either done by yourself or we can do it by selecting the re-spacing labour option for $88 in the RS carbs accessories page
A= 77mm (spacing centre to centre between carb 1 & 2)
B= 93 (carb 2 & 3) see note below if different
C=77mm (carb 3 & 4)
If the centre spacing between the centres of your carbs #2 and 3 is 85mm, rather than the as supplied 93mm, two of the outside carbs will need to be unbolted and then slid in so as to align with the second set of provided securing points and then re-fixed. Due to limited demand for these carbs to suit 86-87 Yamaha FJ 1100 and 1200 engines along with some other applications with the 85mm centre measurement the factory no longer markets them assembled in this configuration thus requiring you the end user to make the adjustment and then re-synchronize the slides.
The carb dimensions for motor and air-box fitment comparison are listed below and reference to the dimensions picture. If these dimensions are not matching your cabs we have new engine mounting flanges and or sleeves for up sizing, down sizing and increasing the carbs front to back length to match most OEM items. When purchased in conjunction with a carb kit, sleeve to carb fitment is complimentary. All sleeves along with any other accessories are found in the “RS carb Accessories” pages located in the main menu “RS Smoothbore Kits” option’s drop list.
A= The OD at the motor end on 38’s is 42mm
D= OD at the air-cleaner end is 55mm
B= Front to back length is 100mm
Pilot Jet: VM28/486-17.5, Needle: 9CHY3, Needle Jet: Y-6 (568 Series), Main Jet: N100.604-135
We have twin throttle and cable assemblies available
Velocity stacks which have no form of filter in them (15, 30,50 and 75mm long) for racing
All international buyers are responsible for the payment of their domestic customs duties and taxes charged on imported goods. The duty free threshold and duty/taxes payable rates differ from one country to another and we strongly advise you check your liability before ordering if unsure. Please check your tracking on all international shipments within 7 days to follow their progress and determine if it is being held by your local customs dept. or on their behalf by the Postal Service, who you will need to make contact with using the provided tracking number.
Please Note: Other than exact replacement OEM carburetors, all Mikuni Aftermarket Carburetors and Tuning Components are sold “As Is” for Off Road / Racing Use Only and are not intended or approved for use on vehicles operated on Public Roads or in locations where applicable engine tampering and anti-pollution laws apply.
Andrew (verified owner) –
Wow replaced my stock 32 cv carbs on my GS1200ss these are fantastic carbs with carbs back up service
Glen –
Perfect on my 1991 GSXR 1100- great straight out of the box! Highly recomended
Jeff –
Purchased a set of RS38’s for my “85 GSXR 750 as a replacement for the aging OEM items that were on the bike. She is used for track only in P6 racing in both NSW and Vic. The first real outing with the carbs installed required an adjustment to the jet needle which came out of the box on the 2nd top slot. Once I adjusted all of the clips to the 2nd from the bottom, riching up the mixture in the mid-range, the carbs provided excellent power across the rev range. I am yet to dyno the bike since the carb upgrade however, the feel is that there is a power increase across the rev range. The bike is pretty much standard, though I have freshened up the top end, with valve seats ground, bores honed and new rings on the pistons. I run a fairly open race type 4 into 1 exhaust and no filters on the carb inlets. This may change in the future but will need to be dyno’d first.