rs34's

The bike runs smooth at the above jetting, but the plugs were bone white. i've worked up to 137.5 mains, needle clip3 and 1/2 turn out on the 17.5 pilot fuel screws. still bone white.
If it's not raining tomorrow , i'll go bigger.

mark1122 wrote:

The bike runs smooth at the above jetting, but the plugs were bone white. i've worked up to 137.5 mains, needle clip3 and 1/2 turn out on the 17.5 pilot fuel screws. still bone white.

White is right. Refer to these plug reading instructions by Larry Meaux
www.empirenet.com/pkelley2/sparkplugreading.html

He is emphatic about not looking at the porcelin for jetting changes.

Look at thread base ring for jetting
Look at ground strap for heat range
Look at porcelin for detonation

I have been rereading that, and many other files i have .I have 6 test plugs now.3 mains,, 2 pilots, and 1 needle(1/2 throttle).
none have any black on the base ring and only 2 show a heat line, on the ground strap.
It sure would be easier with an 02 sensor.

mark1122 wrote:

It sure would be easier with an 02 sensor.

...or a dyno in the garage.

davel wrote:

mark1122 wrote:

It sure would be easier with an 02 sensor.

...or a dyno in the garage.

your such a tease.:lol:

With my 1200cc with rs34's I ended up with 20 pilots 1/8 turn out,3 clip,122.5 mains, it getting hot outside 80-95 may have to rejet it the cooler temps.Checked the compresion 170-175 on all 4 cylinders. I have 500 miles on it now ,its time to take to the drag strip.

Thanks kaw. thats good to know.
i dont know why it is lean ,i was ok with 127.5 mains in my 1327?
i just put in the 20 pilots at 1/8th turn.and 140 mains.
i will keep going up on the mains untill it feels rich. when i back out of full throttle, to 3/4, and it gets stonger, i know i am too big. i like to keep checking the plugs for color too. i think of it as a good learning tool.
It is cool and rainy here.
What do u have done to the head and cams? Pipe?
How did u determin the right size?

Here is how it was set up.head also flows some good numbers.




Bore- 2.992"

Stroke- 2.596"

Head Gasket Thickness .043"

Head Gasket Diameter 3.012"

Piston Height .003" above Deck

Combustion Chamber 36cc

Dome Volume 10cc

Compression Ratio 10.75/1

Displacement 1200cc



Valve Spring Information for Web Cams Springs VS-K10 Intake Exhaust
Installed Height 1.320"- 1.340" 1.320"- 1.340"
Seat Pressure 90psi 90psi
Open Pressure 240lbs@.425" lift 240lbs@.425" lift
Max. Valve Lift .425" .425"
Coil Bind .575" lift .575" lift



Camshaft Specifications for Web Cams Grind #110 Intake Exhaust
Valve Lash .006" .006"
Valve Lift .395" .395"
Duration 284* 284*
Duration @ .050" 256* 256*
Lobe Center 106* 108*
Lobe Seperation Angle 107*
Valve Opens 22* Before TDC 56* Before BDC
Valve Closes 54* After BDC 20* After TDC
Cams Installed @ 106* 108*



Valve Information Intake Exhaust
Head Diameter 37.5mm 31mm
Installed Height #1 - #4 1.486" 1.485"
Valve-Valve Clearance @ Seat .180"
Valve-Valve Clearance @ Overlap .059"
Valve to Piston Clearance >.130" >.130"
Cylinder Head Information Intake Exhaust
Valves 37.5mm SS "J" Model 31mm SS KZ 1000
Retainers Stock Steel Stock Steel
Keepers Radius Groove Radius Groove
Springs WC VS-K10 WC VS-K10
Spring Shims
Cylinder 1 0 .015"
Cylinder 2 0 .015"
Cylinder 3 0 .015"
Cylinder 4 0 .015"
Shim Bucket Type SOT SOT
Valve Shims
Cylinder 1 2.6mm 2.5mm
Cylinder 2 2.6mm 2.5mm
Cylinder 3 2.55mm 2.5mm
Cylinder 4 2.65mm 2.5mm
Valve Angle Cut 2 2
Seat Angle Cut 3 3
Cylinder Head Type KZ 1000


Piston Information on JE #132493
Rod Length 5.3905"
Dome Height .190"
Compression Distance .979"
Valve Pocket Depth Intake .140" from Deck
Valve Pocket Depth Exhaust .080" from Deck
Top Groove .040"
Second Groove .0485"
Oil Groove .111"
Pin Diameter .669" = 17mm
Pin Length 2.253"
Pin Retainer JE .050" Wire Lock
Target Piston Weight 226g
Piston to Cylinder Clearance .0025"



Crank Shaft Information
End Clearance- Out of Cases .014"
Connecting rod Side Clearance
Journal 1 .016"
Journal 2 .015"
Journal 3 .015"
Journal 4 .016"
Crankshaft type Mark II - Welded
Rod Wrist Pin Diameter 17mm



Cylinder Information
Sleeve Type Weisco 1200cc- New
Ring End Gap Top Second
Cylinder 1 .014" .020"
Cylinder 2 .014" .020"
Cylinder 3 .014" .020"
Cylinder 4 .014" .020"


Carbuerator information
Carbuerator Type 34mm Mikuni Flat slide
Main Jet 122.5
Pilot Jet 20
Accelerator Pump Yes
Needle Location Center
Needle Length

I think (fingers crossed) I finally have the RS34's dialed in pretty well. The bike is running really well but the slides still clack more than I'd like. At least it runs well and the plugs look good too. Here's what I finally ended up with:

Carburettor info (RS34 Flatslide smoothbores)
Main Jet - 130
Pilot Jet - 17.5
Mixture screws - close to 1/2 turn, adjusted with colortune
Accelerator Pump - adjusted to mikuni specs
Needles - clip in center groove
Float Height - adjusted to 17mm when float tab just touches needle valve
Synchronized with mercury vacuum gauge

These are waaaaay different than they were when received brand new. I can't believe the work it took to dial them in. No way were they "bolt on".

Thanks for all the tips!

that is one of the problem with flat slide carb's is the noise from the slides themselves i did a zx7rr engine job ad when i fired it without the air box to set every thing it sounded like it was coming apart as soon as i put the air box back it became quiet. but i can handle a bit of noise if it means the bike is going to make stupid power.

Yea, mine are probably as quite as they're going to get. You don't really notice it except at idle. I still wonder how it would run with my old 33 or 29 smoothbore roundslides??

I'd like to pick up a pair of round slide Keihin RS carbs someday, but those are pricey. I wonder if the Keihin flatslides rattle too??

about the only flatslides that dont rattle alot are the ones everybody is putting on there harleys the 42,45 mm mikuni flatslides are supported by roller bearings up and down bothsides so it keeps them quiet.