What carb to buy? (86 atc 250r)

[Dynofox]

I'm in the market for a new carb for my 86 250r but can't decide if I should just buy a new pj 34mm (stock carb) or go with a 35-36mm pwk. The only mods to my motor are boyesen carbon fiber reeds and a uni filter. I don't ride the machine much and only trail ride it when I do get it out. My only problem with buying a pwk is I really have no idea where to start with jetting where as going with the pj I can run what I am now. What do you guys think? Anyone know any good web sites to order carbs from?

[deathman53]

I'd leave the stock carb on, it works good with stock components. a bigger carb will not run to it potential without a pipe,

[atc86r]

why do you need a new carb?

[Dynofox]

why do you need a new carb?

It leaks out of the over flow even after I've installed a carb rebuild kit and cleaned off the (new) needle/inside the seat as best I can with compressed air. The float has been set to the correct level (16mm) as well. From what I can tell the seat is worn out and can't be replaced on the pj.

[TravEX]

Mine leaked alot too, till I took Teamgeeks advice and blew air threw the fuel line and raised the float till I couldn't hear air flowing anymore, and adjusted it to that point, worked great.

[Dynofox]

Mine leaked alot too, till I took Teamgeeks advice and blew air threw the fuel line and raised the float till I couldn't here air flowing anymore, and adjusted it to that point, worked great.

Do you remember how far you had to adjust the float from the recommended 16mm? I will have to give this a shot before I buy a new carb. :p

[TravEX]

I don't remember if i measured after that or not. It wasn't far off if I remember right. It was a life saver for me, cause I was about to buy another carb too!

[TravEX]

I re-read what I wrote and it's confusing.

With the float bowl off, hold the carb in your right hand the way it sits on the trike, I pre-measure the 16mm (about parallel with the bottom of the top half of the carb), and I hold my thumb on the float at about that level, lower the float and blow air through the fuel line, raise the float till you can't hear air coming through the needle and seat. I adjust it so that just as the float reaches parallel the air stops.

Quick and easy. Worked great on mine.

[hrc85250r]

GO BIG OR GO HOME, either get a 38 or 39mm keihin pwk. all there is to jetting is just use common sense, the bigger the number the more gas you will get in the motor and the plug needs to look ike a medium brown. you will be happy when you get an extra 5-6 horsies under you crotch.

[cchap45]

38 pwk air stryker with CR 250 intake / reed block. but it would be best to match it up with some motor work and a pipe.

[Mr. Sandman]

Dynofox, Others on this board will argue that the stock 34mm PJ is junk, but for a mass produced unit and with the minimal mods you have done to your bike a stock carb works fine. I personally wouldn't go any bigger than a 36mm PWK. A 38 or 39mm Air Stryker is a great carb but will be too much carb for your bike. If you are planning future/additional mods such as a pipe, porting, big bore kit, etc, then the 38/39 is the way to go.

[atc86r]

How much are you going to spend on the carb? New or Used?

[3Razors]

The stock PJ34mm is a good carb. Unless it is totally wore out keep it. Beware on the aftermarket carb. rebuild kits. The quality of the kits is very lacking! The kits do not come with genuine keihin or mikuni components. A great place to look is www.carbparts.com they have virtually any piece for mikuni/keihin carbs.

[Lomax]

I put a 35MM Kehin (or however you spell it) from ESR on mine. They asked me on the phone what mods were done to the machine, Then they jetted it for what they thought would be best for me. The only thing I had to do when I got the carb was adjust the idle, everything else was perfect. Its under 300 bucks for the carb and the new throttle cable too.

[Dynofox]

Thanks for the advice everyone, 3razors you make a good point about the carb rebuild kits, I may try a genuine keihin needle (vs the one that came in the moose rebuild kit) and see if that fixes my problem. I'm also going to give travex's suggestion a shot and see how that works.