View Full Version : Issues with carb
Vx21rsjohn
11-03-2018, 11:03 PM
Ive bought this carb
GooDeal Lawn mower Carburetor with Air Fuel Filter (for 110cc 125cc 140cc Pit Dirt Bike) https://www.amazon.com/dp/B01FS6M3W8/ref=cm_sw_r_cp_apa_i_X.L3Bb7ATPFAA
And I'm using a 95 main jet. When I start the bike it idles high(7-8,000), so I thought the idle screw needed to be turned back some. That doesn't work. I've adjusted everything. Fuel mixture screw(just to see if it would help) clip position( only from middle to first) and adjusted the throttle cable. I can not seem to figure out why it's idling so high. It's pretty rich as plug is wet from fuel but I can not adjust it. Anyone experienced this?
Everything is pretty snug as well so I don't believe it's a vacuum leak and I took all the emission stuff off. Just have an crankcase breather.
JerryHawk250
11-04-2018, 08:05 AM
Slide in backwards or not enough slack in throttle cable.
Whisky
11-04-2018, 10:02 AM
I had the exact same problem, pulled my hair out for a week, Jerryhawk said it, not enough slack in the throttle cable was what solved my problem and a couple vac leaks, also trying to adjust idle at idle screw on carb. Needs to be adjusted at throttle on handle bar first then on carb. Clip on my needle is on 2nd from the top. If you look up my thread "new carb on but" you will see exact issue you have. Its not the carb but a tuning issue. Also make sure the choke is off--down position, Also check for vac leaks.. theres a canister ziptied to the frame behind the plastic side cover.If u didn't remove it Thers 2 vac ports on it that need to be plugged. I thought when I changed my carb I got all the emission stuff off, I didn't realize there was that canister tucked in there.
Whisky
11-04-2018, 10:45 AM
Post back with what you found or didn't find. I wish the thread title could be edited so when a fix was found it could be noted on the original thread.
Vx21rsjohn
11-04-2018, 02:13 PM
Post back with what you found or didn't find. I wish the thread title could be edited so when a fix was found it could be noted on the original thread.
My issue: I was using the stock carb throttle cap( I didn't think it mattered). It was causing the slide to not fully seat. I took it off and installed the one the carb came with, and it idles as it should. I took all the slack out of the throttle cable when i installed the carb; I was using the wrong carb cap. Now I have to tune it. I took it for a ride, and I felt a little hesitation at full throttle. All jets are the same as the carb came. I think I need to up the main jet to 100-120.
Whisky
11-04-2018, 02:48 PM
Cool now we are getting somewhere. How many turns out is the a/f screw? That will tell you if you need to go bigger/ smaller main jet. 3 turns or more=bigger/ 1 turn or less=smaller. Mine is running a tiny bit rich still but don't want to run lean. As you make adjustments to carb, my advice would be stay close to home for awhile and make your rides for a longer time so you don't get stranded. I stayed within 6 blocks and kept adding time as I tuned. If I break down now it wont be because of a carb/tuning issue. I ride 30-40 miles around city now and no worries. I also replaced the cone filter it came with with a larger foam one.
Vx21rsjohn
11-04-2018, 04:21 PM
I have to look at carb tuning guides again. Carbs are pretty new to me. I know the clip on the needle is in the second to last notch from the bottom.
Whisky
11-04-2018, 05:54 PM
The higher it is towards the top the farther needle seats into jet and the leaner it will be at idle. I don't know much about carbs either, only what I've learned from here.
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