Share your upgraded carb info!!

[DonLawson84]

I know from Googlin that this subject is beat to death and its pretty overwhelming how many carb and jetting options and discussions there are.
I am in DE (not far above sea level)
The bike is a Apollo ADR125 (RFZ125) I bought for my son and it has been sitting over a year. Though past experiences this new ethanol gas turns to goo and then if sitting long enough black tar, so I plan to just replace the carb.

Anyone with the same motor and about the same elevation please share which carb and the size jets you used so I have a good baseline to setup.

[dirtbkr188]

I use this carb (https://tboltusa.com/store/tbparts-20mm-carb-kit-br-for-z50-xr-crf70-and-xr-crf50-with-race-head-p-575.html) and these settings:


The 20mm ShengWay carb is relatively easy to tune right out of the box. It comes with the #89 main and a #35 pilot jet, both of which you can buy the extra jets from TrailBikes or any TB sales rep. As a baseline setting, I use the #90 or #92 main jet, the #38 or #40 pilot jet, set the jet needle e-clip in the 3rd or 4th notch from the top, and the air screw at 1-1/2 to 1-3/4 turns OUT from seated. Make the necessary air screw adjustments IN to richen it a 1/4-turn at a time and see what the bike does. With some of the carbs, I've run it to within a 1/2-turn of being all the way IN to get rid of 98% of the off-idle hesitation. You might have to raise or lower the clip on the needle, depending upon your altitude, I'm at sea level.

[DonLawson84]

Thank you for sharing the info, when i click the link the description says a carb for a 50cc-70cc. What size bike is it you put the 20mm shengway on?

[dirtbkr188]

I've used it on engines ranging in size from 75cc to 125cc

[DonLawson84]

Thanks, I pulled the carb last night and had the black goo residue pouring out. First carb I had seen with what looks like factory screws with a round head making the bowl inaccessible, makes me wonder how they put them in