Andy bauska 27 Posted December 3, 2021 So, I did a carb rebuild in my 1993 300. It idled great, but when the throttle was wide open, it wouldn't rev up all the way. My brother thought the needle was out of adjustment. I tried it in several positions, and still no luck. My brother thought it might be a too small jet. (We put the new one the kit came with it) the jets in question are both a 125 size. My brother suggested I swap it back out to the original, because it might be too small. So, I took it apart again tonight and found that they were both a 125. So I swapped them out just because I was down that far. When I put it all back together, it won't idle now, unless it has full choke. So, I need some help, I really hope this forum is better than Hondaatvfourms.net, Nobody will give you the time of day there. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted December 3, 2021 My first guess would be a diaphragm problem , crack or hole in it , misaligned under cover and not sealing , vacuum port to it clogged 2 Share this post Link to post Share on other sites
Andy bauska 27 Posted December 3, 2021 (edited) Well, I cleaned the diaphragm with brake clean. Being very careful not to get some on the thin rubber. I only cleaned the hard plastic, and the needle. I only did this because I heard that it might cause my vent line to stop leaking fuel. It still leaks BTW. Edited December 3, 2021 by Andy bauska Share this post Link to post Share on other sites
Goober 1,555 Posted December 3, 2021 fuel coming from vent line? or fuel coming from carb drain line? Share this post Link to post Share on other sites
Andy bauska 27 Posted December 3, 2021 Which is which? The fuel is coming from the one that hangs down. It attaches on the bowl of the carburetor. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted December 3, 2021 47 minutes ago, Andy bauska said: Which is which? The fuel is coming from the one that hangs down. It attaches on the bowl of the carburetor. The vent hose on bottom on the bottom of the carb is the over flow tube , your float / needle valve is sticking or the tank is crudey and specks of rust or dirt is getting in the needle valve causing it to leak Share this post Link to post Share on other sites
Andy bauska 27 Posted December 3, 2021 The bowl was pretty junky, So I need to clean it more? Share this post Link to post Share on other sites
jeepwm69 7,719 Posted December 3, 2021 57 minutes ago, Andy bauska said: The bowl was pretty junky, So I need to clean it more? Yeah, sounds like you still have a dirty carb. Go get you a gallon of Berrymans, open it up, take the carb apart and dunk the body, jets, bowl (don't put in anything rubber/plastic) in the Berrymans and leave it for 24 hours. Blow everything out with compressed air when you take it out. You'll have to polish the brass seat for the float needle with a qtip or 0000 steel wool to make sure it's perfectly smooth, and get a new needle for the float if you didn't just put a rebuild kit in the carb (which would have come with a new needle). If you're on a super tight budget you can boil the carb body in lemon juice and water (50/50) on a campstove and it does a pretty good job of getting the goop out of carbs, but Berrymans works better. Put an inline filter on the fuel line between the tank and carb. Share this post Link to post Share on other sites
Fishfiles 20,147 Posted December 3, 2021 1 hour ago, Andy bauska said: The bowl was pretty junky, So I need to clean it more? If the bowl is " junky " , the junk has to be coming from the tank , to clean the carb is a waste of time , if you don't clean the tank if the carb was dirty , cause the junk is going to go right back in carb Share this post Link to post Share on other sites
Andy bauska 27 Posted December 3, 2021 When I bought the bike, the tank was rusty, I'll throw in a pic. Since I changed the color of the bike, I bought a nice rust free one from a 1996. The carb probably just had residual rust from that tank. I sandblasted the bowl, and cleaned it real good, So I'll see if it runs better. I got the choke thing figured out btw. Not gonna lie, it actually ran pretty good on that. And yes, I do have an inline fuel filter. 1 Share this post Link to post Share on other sites
Goober 1,555 Posted December 3, 2021 (edited) Well actually the overflow tube itself is in the carb bowl. When fuel overtops the top of the tube, fuel will flow out of the bowl drain line. Make sure the overflow tube inside the carb is not cracked. Brass stem in carb bowl also make sure your bowl drain screw is snug. This will also cause leaking. the carb float lifts the float valve and shuts off fuel flow. If the valve doesn’t seat, fuel will continue to drain into the carb bowl and when bowl is full, fuel will flow out the overflow tube. A bad float valve, debris or dirty valve seat, worn/cracked float can all cause continuous flow. Below is pix of 93 carb VE90E Edited December 3, 2021 by Goober Share this post Link to post Share on other sites
Andy bauska 27 Posted December 3, 2021 (edited) Thanks. My brother just got home, and we got it running pretty good. It still lacks on the top end tho, Could this be a fuel filter? And what did you think of that tank LOL😂😂 Edited December 3, 2021 by Andy bauska Share this post Link to post Share on other sites