http://www.holeshot.com/mz/mzsc.html

It's a 42mm Flatslide Mikuni Single Carb conversion kit for the MZ660.

Why wouldn't it work on the Raptor?

 

bash,

Seems like it would have to have different size runners for each side, similar to the stock ones...don't know how else it would balance fuel/air delivery. Tune to the left valve and the right ones would be too lean...tune to the right valves and the left one would be too rich; something like that...what do ya think?

 

Runner size would only have to be big enough so that it wasn't restricing airflow to either side. Whether or not one side needed to be larger or not would be determined on if the side with 2 valves was allowing enough volume of air/fuel to pass through.

I believe that you're thinking too much into the air/fuel delivery. With a single carb, both sides would be receiving the same mixture of fuel and air (a good thing).

 

I realize it is ALL going to the same piston, but since the volume of two valves will be considerably higher than one, just seems it would be a tuning problem, UNLESS, something like runner sizes were different. Somewhere it would have to be accounted for, the stock ones do it by internal size of runners and different size jetting in both carbs. Oh well, maybe I am reading too much into this...sounds like a great idea, I'd be game for one, go ahead Bash, try it, and tell us what ya find...RIDE OUT!

 

Raptorup, (cool name by the way)

The reason the stock carbs use different jets is because just as you mentioned, the carb feeding 2 valves sees more velocity than the carb that feeds only 1 valve. However, when running through a single carb system, the carburetor is distributing a uniform fuel/air mixture without regard to where it goes after it leaves the carburetor.

All 3 valves would be getting the same air/fuel mixture, they just might be handling more or less volume and velocity than the other 2.

 

Almost forgot.

I won't be the first to try it. I have enough power now and am concentrating on handling it all. I'll move up after that.

I simply put the link up for those that are looking to change over to a single set up.

 

it would work on the raptor. jetting and performance gains might differ but do you realy want to try a 42mm carb what about your thumb? it would be time for a twist throttle. plus it says the main gain of the intake is lowend torque... hmmm.. i dont know about you but i think the only thing the raptor needs is a little better rev. any more torque would be scary.

 

You're thinking in terms of a Banshee.... Don't, the Banshee is a completely different animal...

The big single, if anything would lose velocity, hence cause a loss of bottom end & corresponding gain on top.

I really can't see a 42mm single having anything but less of a throttle pull than any dual carb setup.

 

86atc250r

yes you are correct that is the way the single carb set up should work on the raptor but on the site it is claimed to have gains in the low end and not any more top. Maybe they are using smaller intake tracks to keep velocity up. never know. but i do know that the carv they use will hurt the thumb. a buddy of mine has the identical carb on his 440ex and it is a monster to pull so he went to a twist.

 

Hmm,

The heavy pull may be a problem specific to that particular carb. I have an FCR 39 on my EX and it has a very nice pull.... Maybe an FCR 41 would be a better choice than the Mikuni.

The biggest gain I would suspect a person would get would be the throttle response, something the CV carbs seriously lack & something that doesn't show up on the chassis dyno.

The uncorked silencer they were quoting figures with, may explain some of the additional bottom end as well...