Moustache Man
  • Topics: 11
  • Replies: 24
Jan 14, 2020
GV125 2016

Have no fear! I assume that is the Carby model, based on the white speedo/tach gauges.

Yeah I had the exact same issue. Even starting from cold on a warm sunny day, it struggled to switch on. I bought mine off a guy who had it sat around for 6 months, riding home on that thing was a nightmare.

As the carbs are so difficult to access, and you could risk damaging your intake manifolds, it is best to just let the bike run. Use premium fuels if you can, and go to Halfords/any other car/vehicle store and get some fuel additives.

I personally use REDEX.

Another tip – get some carb cleaner spray too. Take off the air filter box on the side of the bike (you will only need a screwdriver). Take off the jubilie clip holding the air filter box onto the intake, so you are left with an open intake. Run the bike, give it a bit of throttle and spray the carb cleaner into the open air intake. You should feel the revs increase, then the bike bogs down afterwards. You will find a good routine eventually.

Another tip as well, adjust your idle screw. Dont adjust it so badly that the revs stay on when you pull the throttle, but adjust it to the maximum before this occurs.

One final tip – the stock fuel hoses are a bit crap. Cheap rubber, will fray and disintegrate. Get yourself the steel braided hose being sold in the shop here. You will struggle to make it fit, I am running mine without the giant fuel filter but it still runs great.

Oh one more thing. With the airbox removed, look up at the carbs.

You should see two tiny little brass screws. These adjust your fuel mixture. Try and get the bike running richer, and just test the screws at different adjustments to see what fits best for you.

A lot of trial and error, took me hundreds of miles of riding and lots of idling tests to get my bike tuned perfectly, without having to remove the carbs and clean them