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  1. G

    Convert Lifan 125 to 140cc

    Hey, i have that question that I have two lifan 125cc engines and both engine numbers are 1P54FMI. I want to put a 140cc cylinder on one of them if it is possible. Are the strokes the same on the 125 and on the 140 or it is different? If different is it possible to lathe to size the 140 cylinder...
  2. G

    Convert Lifan 125 to 140 if possible

    Hey, i have that question that I have two lifan 125cc engines and both engine numbers are 1P54FMI. I want to put a 140cc cylinder on one of them if it is possible. Are the strokes the same on the 125 and on the 140 or it is different? If different is it possible to lathe to size the 140 cylinder...
  3. 20210824_195056.jpg


    anyone know what this bike is?
  4. B

    125cc Diagnosing power issues

    Hey guys, just recently got into pitbikes and don't know the greatest amount but have been trying to diagnose why my bike has no power after 1/4 to 1/2 throttle. The bike has a 125cc zongshen engine with a vm22 Mikuni carb. First ride on the bike it was spluttering in second gear onwards at half...
  5. J

    how in the world does this fuel vacuum (i think) work??? please help.

    i recently swapped engines on my hardknock kikker and am curious about how this fuel vacuum system works as it seems to be connected to the engine. (see attached pics) there seems to be a homemade filter atop the system done by the previous owner. the engine pictured is the original 49cc engine...
  6. F

    Turning a hongdou pw80 into 125cc

    I am buying a cheap hongdou pw80 tomorow, as a project. Looking to put a pit bike engine in it (M2r 110/125) but not sure wich engine would fit inside the small frame. I've heard that any engine that fits in the crf50 frames will fit. Has anyone else successfully attempted this? I know they r...
  7. quintero.eric

    Is the Mikuni 26mm carb the best one for Apollo 125cc

    I got a new Apollo DB-x18 and the carb sucks! I live near Austin Texas and I need to buy a new carb. Is the Mikuni 26mm the best and should I buy extra jets or needles for it? Any suggestions on carb set up for Texas area. I appreciate any help one can give. My 11 and 9 year old boys will...
  8. Generalkrash

    140cc 125cc Franken build. Advice wanted.

    Hello there. We are working on my buddies bike motor and are attempting to build something different He has a gio 140cc barrel and piston we were going to widen the case a bit so the sleeve will drop down. In to the bottom end. The bottom end is a lifan 125cc with the 14mm wrist pin. Piston fits...
  9. Babitzin

    Ycf125cc needs more power?!

    Hey guys! I got an engine from a ycf pilot 125cc and im going to put it on my 110cc atv, but i would like to get some more power out of it. It doesnt have a stator at the moment so i have to buy a new one. Would an inner rotor kit something?
  10. L

    125cc Help Pops and White Smoke upon starting

    So i have a newly built 125cc Pit bike. New refurbished 125cc automatic motor, electric start. Mounted Horizontal. New wiring harness. 1st issue; The manufacturer/ description said they removed all the oil before shipping, so I added 900ml. Come to find out those MFrs actually had about...
  11. D

    Gpx 125cc problems

    Hi everyone and thanks for reading my post. I have a problem with my motor it is a GPX 125CC. I bought the bike and brought it back home I got maybe 15 minutes of time out of it and then they croaked.topped in 4th gear was going about 50 to 55 miles an hour I get back into my buddies driveway...
  12. 21Guns

    2015 Atomik Nitrous 125cc

    So I bought the Nitrous 125cc of Ebay around March for a grand sum of $580 including postage with the expectations of its a chinese bike I'll probably have it thrashed and broken within a few months. It was my first pit bike and first time I'd really ridden an offroad bike. Honestly these last...
  13. my67xr

    Pit Bike Carby id, what carby is this ? Carburetor, Carb, Mikuni, Keihin, Oko, VM, PE, PWK, Flatslid

    Here are some picture's of a few common pit bike carby's These are posted here for a reference to help identify your carby Keihin china copy, Sheng-Way, Jing-Ke PZ16 (16mm), PZ19 (19mm), PZ20 (20mm). PZ21 (21mm) Round bore Carb, ideal for 50cc, 70cc, 90cc, 110cc engine's...
  14. S

    M2R 125cc Clutch problem

    So I recently got a brand new m2r 125cc pit bike and at first pulling the clutch lever didn't engage the clutch, after a few adjustments (to the lever and clutch cable) I managed to get the clutch to work. However it seems like pulling the lever doesn't actually fully engage the clutch. When the...
  15. T

    Coolster 125cc DB214S.. Dead

    Hello. I just joined, so if I do something wrong please let me know. A few months ago I purchased this bike: https://www.amazon.com/gp/product/B00EEJKR2O/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1 A few weeks ago the front gear sprocket threw off the chain, and "blew-up" a lot of things...
  16. BennyG

    Oil Cooler for Lifan 125cc

    Hi miniriders, I'm sure there are threads on this already though I'm very average at navigating this site. I have a Thumpstar 125 TS-E that I want to put an oil cooler on. I ride the thing every weekend for four hours at a time so an oil cooler is something I think my bike could benefit...
  17. criggs

    SSR 125 budget bike

    Hey guys, I recently came across a pair of pit bikes on Craigslist while searching for a cheap, small bike to teach my little sisters on. Originally I was opposed to pit bikes, mostly because they aren't quite intended for learning on. Then, I found an ad that had two for sale at 250 for the...
  18. Asian

    CRF50 Build

    Check the last pages for the most recent updates :) thanks for viewing have fun reading ! My CFR50 Build was a lot of fun and still on going i thought i would share with you guys as i like these threads myself :D i didn't take photos of every mod but did take a few of the build. i started...
  19. Kprugger03

    Crf50 with lifan 125cc prob

    Anyone know what to do when u put a lifan 125cc on a 03 crf50 and the rear foot Break hits the foot peg bar an is under the side of the motor what do you do to fix that???
  20. S

    Terramoto 125cc stator .

    hello everyone i have a terra 125cc with a lifan motor the outta rotor (flywheel) pickup? has broken due to the chain coming off and hitting it. would you recommend to replace with a OE part or get a irk off ebay. do they really work or just a waste of time and more stain or the motor. Inner...