hi i have a 69 ih its a 900 has a mag and zenith carb with drag pipes ok so the accl. pump on my carb went out so i bought a genuine zenith rebuild kit put a new accel pump in put the new o ring in and gaskets and set my float wit a 3/16 drill bit all like it says put it on the bike fired it up wit only 3 kicks good so far set the idle mix screw still good ran down the road and any time i try to put some power to her she feels like it hits a brick wall like theres nothin it sounds like when u hit a rev limiter in a car and i can get to about 45-50 in 4th gear but thats as fast as shell go so ive been fussinwit the adj.main jet started at 4 turns out n im down to 3 1/4 turns out now plugs arnt wet like super over rich anymore still a lil black but idk if i should keep leanin it out cuz i dont wana over lean it does this sound like a main jet problem ? p.s. i also gaped the points there at 15 thousands and look good and and its just a hair retarded on the timing cuz the damn thing would never kick start when i had it timed wit the line in the hole point me in the right direction please and thank you

 

were you driving with the choke still on a little bit?
is the accl pump working ok now?
did the needle valve seat properly?
are you sure it was a carb problem in the first place? If the o-ring was worn then you would have gradually tuned the carb leaner and a fresh o-ring would have required you to richen the carb again.
set the timing properly and try again if everything else checks out ok...or leave the Mag loose enough that you can adjust it once it is running and see if that changes anything.

only adjust one thing at a time though.

 

no chokes deff off i fliped it on while i was runnin down the road to see if it made a difference and she died right out so choke was for sure off and yea the acl. pump works great now it dont leak and it squirts now which it didnt before and as far as the o ring i just replaced it cuz the kit gave me one the old one seemed fine though and as far as the needle seating good idk it all went back on smooth didnt have to fight it any so id think it is but idk but i tightend the main jet and backed it out 4 turns like it sugests as a starting place today i turned it in a lil more so now im 3 1/8 turns out plugs arnt lookin as black anymore so i think im getin closere but not sure like i said i dont wana over lean it and the timing i set it dead nuts and i freakin was kickin forever no start or it pops and nearly sends my *** over the handle bars but once i start it on retarded and set it timed dead nuts it runs the same it seams but i havent taken it down the road wit it like that yet but idk shes pretty damn hard on fuel it seems like only 20 mpg at best

 

plugs arnt lookin as black anymore

are you checking this during a hwy run? or casual driving and around town?

my plugs carbon up pretty good cruzin around town but will tan on the highway.

if the needle valve isn't seating, fuel will be coming out the overflow--don't shut off the petcock when you stop and see what happens.

 

Sounds like scottfisher is on to it. I'm suspicious of your float bowl setting. Even when properly adjusted it can easily get bumped out of adjustment during reassembly. If you're turning the carb over and back too quickly while putting the bowl back it will slightly bend the float attachment. While on the bike it's protected because the bowl is full of fuel. But when empty the thing can actually flop around quite hard. Your running problem sounds like too much fuel, therefore worse when adding choke. Try resetting the float level. Also, make sure the needle is new or perfectly clean as well as the jet where the needle seats. Then carefully reassemble and check operation. If still not right you can overcompensate slightly on your float level adjustments until it seats just right. Remember, bending float down into the bowl seats the needle tighter into the jet and bending the float up seats it more lightly. If scottfisher is right this is what you now have, the needle seats too lightly and fuel will flow faster than needed when running or will overflow when not running if petcock is left on.

 

+1 on this.

 

im runin her down the road as fast as shell take me lol so no not cruzin round town im truin to run it as hard as i can so i can see what it does when im in the main jet circuit cuz thats where i beleive my problem is...... oh and the needle must seat right cuz i forgot to turn my petcok of last night and she didnt leak a drop outa the carb into the air cleaner or anywhere for that matter but idk about the seting of the float ill have to take it off again n see but if its still on 3/16 should i move it different ? or is it all just in my adj. main jet and i need to keep leanin her out some more? cuz im like 90% sure this is a fuel system problem thanks for the help guys keep it comin

 

When checking my plugs, I like to run at speed for a while and then pull in the clutch, kill the engine, and coast to a stop. That way you don't get any false readings if you need to cruise through a neighborhood, etc. to get back to the garage. Probably overkill.....

 

+1

It is not overkill. I find i have to go for a longer hiway run, say half hour or whatever, to really clean up the plugs; then do the "plug chop" as you describe to get a plug reading for the main jet; then a short ride [5 minutes] with little if any idling thru the city on the way home; then read the plugs for the slow jet.