22mm mikuni or gx390 carb?

[Creeper]

I'm fairly new to small engines. I'm looking to upgrade my carb for a Clone 6.5 which is on a custom mini chopper frame. Which is better Mikuni or GX390? What are the advantages and disadvantages between the two. What would be the cheapest price range for either setup. Thanks for your knowledge in advance.

Creeper:gunsmilie:

 

[GTO]

I'd go mikuni , it's adjustable. Price isn't much different depending how you shop.

 

[Strigoi]

i'd go with the Mikuni just because it uses a dirt bike style throttle setup. that makes hooking up the throttle much easier.

you can find the cheap 22mm Mikunis on ebay for around $30-35.

 

[Solo Cali]

I have both, and have used both on a Suburu Robin 6.0 with mild head work and to be honest I like the 390 carb better set up. Maybe the 1/2 hp is why, but it runs better compared to the 22mm Mikuni, for me I'm saying. Throttle cable is a breeze either way.

 

[minidragbike]

My buddy JD prefers the gx390 carb. I have never liked them personally.

 

[Creeper]

I'm leaning towards the Mikuni. I found a 22mm($34.99) or a 26mm($39.99) at WickedMX.com. How easy is the throttle hook-up? And how easy is it to tune?

 

[Strigoi]

i'd contact wickedmx before ordering one. he said he wasn't going to carry them any more because they weren't selling. last i heard he was all out of them.

i ordered mine through him quite awhile ago. he's pretty good at getting back to you on questions.

 

[Creeper]

Thanks for the heads up. I'll shoot him an email.:thumbsup:

 

[Creeper]

Which of the Mikuni on ebay will work with the adaptor?

 

[Solo Cali]

My buddy JD prefers the gx390 carb. I have never liked them personally.

In stock trim, or re-jetted?

 

[Creeper]

How big of a Mikuni would you suggest running on the 6.5 clone?

 

[Strigoi]

depends on what you have done to the engine. if it's pretty much stock one of the cheap 22mm ones will be fine.

 

[Creeper]

I took out the govenor, upgrade to 18lb springs, high flow air filter for now. I want to do more in the near future. So I want something that can handle what I got right now but be able to handle what I put on it later on down the road.

 

[Creeper]

Well I went with a 24mm Mikuni($34.95) on ebay.

 

[Solo Cali]

How big of a Mikuni would you suggest running on the 6.5 clone?

A stock clone ?

 

[Solo Cali]

I took out the govenor, upgrade to 18lb springs, high flow air filter for now. I want to do more in the near future. So I want something that can handle what I got right now but be able to handle what I put on it later on down the road.

I think the 24mm is too much carb for what you have, a rejetted stock carb would do I would think .

 

[Creeper]

Solo Cali
What enigne MODS would be good for a 24mm? Next month I plan on buyin some more parts to add.(rockers, molly rods, top plate + fuel pump) I want to advance the timing too but I need alittle more info before I do that. I also want to do bigger intake and exhaust valves. What would happen if I ran the 24mm on there right now with the setup I have? What jet would you use on a stock carb? Thanks!!

 

[minidragbike]

In stock trim, or re-jetted?

I guess rejetted to work on a slightly mod gx200.
I only run aftermarket carbs myself. And back when I use to run the 22mm Walbro carb it worked great, and I even ran the 26mm before as well.

 

[minidragbike]

Solo Cali
What enigne MODS would be good for a 24mm? Next month I plan on buyin some more parts to add.(rockers, molly rods, top plate + fuel pump) I want to advance the timing too but I need alittle more info before I do that. I also want to do bigger intake and exhaust valves. What would happen if I ran the 24mm on there right now with the setup I have? What jet would you use on a stock carb? Thanks!!

You only need a 22mm carb at most, they are good up to 12hp.

With the 24mm carb you need more head work, maybe a small cam, billet rod, billet flywheel.

You need at least a billet rod for anything you do.

 

[Creeper]

Ok guess I will save the 24mm Mikuni for later on down the road. Thanks for all the info!