Home Forums Shifter Karts Possible gear box issue?? Reply To: Possible gear box issue??


Christian Hubbell

I just went through this with my kart.  I was getting a false neutral in 5th gear and the motor would zing and not put down power.  There are two different main shafts for the different years of a cr125, I thought I had the wrong one but this wasn’t the case.  If you search this site for “5th” and the old ekarting news forum you can find the part numbers.  Take a closer look at your gears again, I thought mine looked pretty good but they were indeed rounded on the dogs.  It was expensive to fix but no issues with the new pieces installed.  Personally, I think there is too much gear play on the secondary shaft  and thought about adding a shim to help hold it in gear but decided against that.  Check that there is a lot of space for the shift rod next to your  seat too, I saw marks on my seat and it was flexing in fast lefts and pushing on the shift rod while on power (bad).