which rs carb for a 1260

for a 1260 with a ported head and 435 cams that is intended for a street strip bike(a weekend bike not a daily rider) would you go 34mm or 36mm flatslides?

Also if you were to turbo it would the carb size change? would smaller be better or bigger or same as a normal breather? thanks

Mr. Cavanaugh can probably give better advice on the carbs but personally, on that set-up, I would go with the 36mm. 34's might give better throttle response while riding around but the 36's should be better for the racing part of the deal. As for if you went turbo, and I will asume it will be a normal set-up with the turbo behind cylinder and not a blow-through style, get a 42mm HSR Mikuni. This carb is fantastic for this set-up. Actually about the only carb anyone uses for a turbo on a KZ.

www.mrturbo.com/catalog/106_carbfuel/carb_fuel.html

A source for the Mikuni HSR.

I haven't seen many (any that I can recall) turbo setups with a 4 carb install. Most simplify to a single carb. I'm assuming this is mostly due to space and ease of tuning.

If you use a blow-through system you still use the carbs unless you switch over to injection of some kind. Blow-through will generally make more HP but on these older bikes, it's a lot more work. Newer bikes use the blow-through systems.

Don't the blow-through setups require specific carbs with pressurized float bowls or something similar?

I think Racer54 is right on the money

N/A 1260 motor with good head for race use, Mikuni carburetor.... RS38

Street / Strip....RS36

RS34 can deliver enough CFM for the job and would give awesome midrange. However for the money and future growth potential.....RS36 would make sense.

Typical ported J w/ stock valves should be in the mid to high 90's CFM at 10". I just posted results of RS34 flow test in another thread.

I'm not a turbo expert by any means, but I have heard that on a blow-through the bowls have to be pressurized but I ahve read that isn't necessarily true. Don't know why though. I know some use CV carbs. I hear some run a tube to the float bowl to pressurize the bowl. Maybe it depends on the boost pressure run?