I have been wondering since i first discovered how they work... Will a CV style carb still work and pull your butt down the road if the slide dosnt move at all? The answer is yes! I have a customer that has been losing power and speed with his GY6 powered 49cc scoot. He did all the "norm" stuff, checking and changing fluids and filters. It ran a little better but still wasnt running up to par. 40MPH indicated with the stock speedo. He brought it to me yesterday and the first thing i checked was the diaphragm in the carb. There was a little hole in it preventing the slide from even working and enough air from getting into the engine. He said he has a spare at home so i didnt put a new one in right away but im sure this is what caused his lose in power lately. I went ahead and checked the valves and they were still right on from last summer. I will call him today and see how much that helped. Im sure he is right back up to the norm again
Yep, that was the problem :thumb: . He called me yesterday and told me that he put a new one in and it runs good again. Indicates 50+MPH on the speedo. What i find funny about the whole thing is just how well it ran with the diaphragm torn :spin: . It would still do 40 and didnt miss or anything (when i road it), it just felt lazy and flat :stumped: . When i took the top off the carb i tried to pull the slide out and it was stuck in the carb. I knew right away what was up....
You can repair the small holes w/RTV silicone. Just have to clean the surface well and let it cure for at least 24 hours. I use Rubbing alcohol to clean the rubber first being careful not to make the hole bigger.