bigger then normal carb

[mizke]

so i am getting sick and tired of my stupid keihin or whatever carb.. its a not a true real one either.. so jets are a HUGE PITA to find.. the one i ordered from rockymountain was like half the over all size of the ones in it..

so i am upgrading to mikuni carb.. was going to go with the 30mm carb every one else has.. but my theory to life is, go big or go home..

has any one used a 32mm or 34mm mikuni carb ?

i know it wont bolt up on the intake tube, but i can cut the tube a few inches behind the flange the carbs bolt to, and use a section of rubber tubing to mount the carb.. every one says the 30mm carb gives a big ol boost in power, and my current carb is a 30mm.. so i lead to believe that a 32 or 34 mm carb will give a really really big ol boost in power..

this is what i was thinking about going with

http://cgi.ebay.com/ebaymotors/34mm-...Q5fAccessories

[mizke]

32mm carb

http://cgi.ebay.com/ebaymotors/MIKUN...Q5fAccessories

[TYE]

the pz30 upgrade is great. maybe this will be better but i think a rad hose (or watever) extender might eliminate the added power. also im not sure but i dont think an engine can just withstand a jump as large as that without adjusting valves and possible boring??? good luck anyways

[mizke]

i know that in cars you can make a lot of power but a simple turbo or supercharger add on. with out having to do internal work, sure my motor in the quad would make a lot more power with cams and boring it out.. but it should still make more power safely with the stock cam and piston aslong as i jet it properly

[TYE]

hopefully because that would be sweet but id wait for waynev or w&g to chime in. i usually do

[mizke]

ive been pming w&g about it, and i guess the motor could make good use of a 32mm carb.. maybe one day if i put in a different name brand motor and cam it or happen to find cams that will work in this motor, i will give it a try

[TurboT]

Your valves and intake port will only add a certain amount of air/fuel into the motor at one time no matter how big the carb. In order to substantially handle any larger air/fuel flow from the carb you'd need to increase valve head size(or opening amount re cam), intake manifold size, intake port size, and carb size. Then, you still need to move that spent air/fuel mix out the exhaust as well. (exhaust valves are smaller yet)

You could be landing in overkill mode by increasing your carb diameter. Remember your intake port on your head is going to be sized similarly as the carb and intake opening.

[mizke]

thats pretty much what w&g just said in a pm about it.. so i guess a crappy ol 30mm mikuni is what im going to go with..lol..or find a turbo.. that wont happen, this motor is not worth it to boost and i doubt it could handle it even tuned correctly for any decent amount of time to make it worth it

[waynev]

Originally Posted by mizke

thats pretty much what w&g just said in a pm about it.. so i guess a crappy ol 30mm mikuni is what im going to go with..lol..

The 30mm mikuni with the UNI air filter and a free flowing exhuast really wakes up these 200cc engines when properly jetted, i'm sure you could make a 32mm or 34mm work but i'm not sure you'll gain much more than a well tuned 30mm setup unless you want to do more engine work to maximize the extra fuel and air you'll be getting from the bigger carb, and by the time you do that you might as well just stuff a 250cc in it.

[konman707]

seems like you would drown it out to go that big. like turbo said it can only let in so much.....

[Weldangrind]

Originally Posted by TYE

hopefully because that would be sweet but id wait for waynev or w&g to chime in. i usually do

Waynev is the man. 8)

[waynev]

Originally Posted by Weldangrind

Waynev is the man. 8)

Easy now, i just bring years of fabrication skills and many more years than that tweaking mikuni carbs on my snowmobiles and microsprints so i have learned a thing or two about them and i'm glad to share them all with you guys.

[mizke]

well now to find a hot cam that will fit in my top end.. or a stock honda/yamaha top end.. dont know if i trust my top end to handle a hot cam

[anthonyfa18]

Originally Posted by waynev

The 30mm mikuni with the UNI air filter and a free flowing exhuast really wakes up these 200cc engines when properly jetted, i'm sure you could make a 32mm or 34mm work but i'm not sure you'll gain much more than a well tuned 30mm setup unless you want to do more engine work to maximize the extra fuel and air you'll be getting from the bigger carb, and by the time you do that you might as well just stuff a 250cc in it.

so do u thing that if u have a 250cc engine you should put a carb bigger then 30mm for more power????

[TurboT]

Originally Posted by anthonyfa18

so do u thing that if u have a 250cc engine you should put a carb bigger then 30mm for more power????

That would really depend on the mathematics of the head in the engine. If you have bigger valves and intake/exhaust ports to match the cylinder/stroke you could make a bigger carb work.

My guess is the valves and ports are similar size, and a bigger than 30mm carb isn't necessary on 250cc either.