24mm PWK over stock 24mm CVK

[joeorange]

As the title says, would there be any benifit to having a 24mm pwk over the stock 24mm cvk on a GY6 125?

[90GTVert]

I've never tried a slide carb like that on a 4T scooter, but here's something to check out :
buggynews.com/cv-carb-vs-round-slide-flat-slide-other-variables-t9522.html

[joeorange]

Hmm, okay, i think ill give my pwk a try when i get the Gy6 mounted to my scooter.

[visthum]

This is just my opinion but i think the CV carb is what your should use for 4 stroke, they just kinda work OK in any condition, climate and altitude.

I read somewhere that slide carb might drown 4-stroke engine if not careful and is more sensitive to get right and his conclusion were - CV 4 stroke - Slide 2 stroke for best results.

I'm curios about the performance if you decide to try it, might see increase in top-end, or i Know you will see increase in top end performance with pwk.

[joeorange]

Oct 12, 2016 7:21:50 GMT -5 visthum said:

This is just my opinion but i think the CV carb is what your should use for 4 stroke, they just kinda work OK in any condition, climate and altitude.

I read somewhere that slide carb might drown 4-stroke engine if not careful and is more sensitive to get right and his conclusion were - CV 4 stroke - Slide 2 stroke for best results.

I'm curios about the performance if you decide to try it, might see increase in top-end, or i Know you will see increase in top end performance with pwk.

ive run slide carbs on 4 strokes before and they have worked out great for me. mind ya they were used on motorcycles not scooter engines with a cvt, but i would think they would work just fine.

[joeorange]

okay, in another post i said i ended up accidently breaking my stock 24mm cvk carb, i decided to give my 24mm pwk a try and see how it works. well my engine starts up fine with it, as long as you use the choke. and it revs up real good with it. but so far i havent tried actually driving the engine under load with the pwk. the one thing stopping me is the throttle cable placement. because the pwk throttle cable sits on top of the carb not beside it like the cvk, i cant use my seat with the carb unless i either cut out the seat bucket, and id prefer not to do that since it would render the benefits of a scooter null, and the other option is to get a new pwk top with a 90degree bend. and at this time i dont have the money to get a new top.

my other option is to get a new cvk carb, i have been looknig at the 26mm racing cvk carb from nibbicarburetor on ebay, and they seem pretty enticing. mostly because of the throttle cable mounting is changed and also because they have an accelerator pump on them.

[joeorange]

well its official. ill need to get a new cvk carb. now while the engine idles and revs great with the 24mm pwk, the engine is gutless with it while there is a load on the engine. and swapping jets didnt help the pwk any.
so next pay i am going to have to get a new carb. and i think ill get either the 22 or 26mm cvk from nibbicarburetor. as i mentioned before they have an accerlerator pump and the throttle cable mounting location is alot more forgiving compared to the stock carb. the only downside to the nibbi carbs it that they are a bit more then the stock replacement from scootertuning.ca

[knobby]

I have a Mikuni flatslide 28 on my 4T. No pump, runs great, no problems. My experience is the opposite of the buggy forum post.. my stock CV carb had all kinds of issues.

The original PWK design was for 2T engines. Not to mention what you've got is probably a copy of a copy of the original. Plus they took a mould from a 28mm carb, then undersized the bore. Which hopefully these guys got that lined up correctly. Should be bored offset on the bottom to keep the same fuel outlet locations as would be on a 28.

I'm not saying your 24 can't work on a 4T, but it could take time figuring out the proper needle.. if one is even available. TM's you can change the the emulsion tubes, but with the PWK you're stuck with needles only.

As far as the cable goes, you can't ADD a 90 bend to your carb? You should be able to.  If yours has a cast in pipe on top, hack saw it off and tap it for a thread in 90.


Edit: Seriously the buggy forum guy is complaining about.. mechanical carbs not working well with an improperly adjusted cable?  Then F'n properly adjust it you dufus!  lolz. 

[joeorange]

i could add a 90 degree bend to the carb, but it would still rub on the bottom of the seat pan no matter what i do with it. i already have the 26mm cvk and it runs great, i just have to get a set of jets for it since the #110 main jets it way too rich for my stock 150cc cylinder. if i had a bigger bore it would probably work fine, but its just too rich atm.

[fugaziiv]

We run PWK carbs on our 4t drag racing bikes. They take some different tuning, but they actually run great, particularly in applications where we run nitrous and want the sharpest throttle response. I'm not however implying that they are a better solution than a CV carb on a 4t bike; simply saying that they can work. Just food for thought.

Matt

[ratracing]

Pwk has a snappier throttle response and better acceleration revs up better. CV is smoother throught the throttle ranges. Almost like the rpm controls the cv carb and the pwk controls the rpm .