I need some help. I'm at a complete loss as to what to do at this point. I recently cleaned my carbs for the first time and now my f4 is hard to start with the choke on and no start without the choke. When it does start with the choke it will rev high but floods out within 30 seconds. White smoke out of the exhaust and smells like unburnt gas. I've taken the carbs back apart and everything looks like it's working and operating as it should. Pilots are set at 2 turns out. Its getting spark but way to much gas. Where do I start to get it right? Any help would be appreciated...

 

Did you replace all rubbers? float-bowl seals, pilot-screw O-rings? fuel-rail O-ring?

Did you replace float valves?
Did you adjust float levels?
Scrub out hidden secret passages with brushes & PEA-based fuel-system cleaner
Ultrasonic soak?
Micro sofa-blast?
Sync carbs?

there's more to "cleaning carbs" than spritzing usesless spray "carb cleaner through. Those don't work anymore due to removal of chlorinated compounds

 

I replaced all of the rubbers that you asked about and the float valves. I didn't think the float levels were adjustable on the f4. I didn't go into the fuel rail so didn't replace that o ring. I took the bowls off and cleaned the inside and replaced all the jets pilots and cleaned where the diaphragms are. Everything is still clean as of yesterday when I pulled jets and pilots. I didn't sync them using any tools but did bench sync them. When I tried to start the bike yesterday it flooded itself out so bad that it smells like fuel down in the crank case. Definitely doing another oil change b4 riding. It will only start with the choke and will rev like the choke isn't on. I don't know. It's definitely getting insanely to much fuel but I can't figure out how or why. Nothing is leaking anywhere. The pilots are set at 2 out which is what I've seen numerous guys on here say is correct. I feel like I'm missing something obvious but not sure what.

 

if it's so radically over-fueling then that points towards the float valves not sealing correctly. Did you capture them correctly in to the plastic float so the spring engaged?

Though Danno is right - that a complete breakdown and service is the ultimate fix, I am more inclined to just get things working and let seafoam handle the rest.

 

Rockpool I think your right that I put them in wrong. I've got a more experienced mechanic looking at it hopefully tonight or tomorrow to see if that is the issue. I'm hoping that it's something as si.ple as that so I can finally get some riding in. I saw another thread where someone got a rebuild kit that had the wrong valves in it so we're also going to see if the old ones will fix the problem b4 I order the actual oem ones. I'll let you know how it turns out

 

maybe - you need to "hang" the valve on the float as you insert them as a pair, then slide in the pivot pin. It's easy to think the valve goes in first and the float on top - but that would hold them full open all the time.

see 5:18 here -
oh and as for float valves, mine are 25 years old and 30k miles - seem perfectly fine - the original honda parts seem to last forever.

 

New float valves don't always seat on old seats well. Inspect seat interface and verify surface is even without pockmarks. Can "machine" them slightly with Q-tips and polishing-compound.

 

I appreciate the help danno and rock. I'll let you guys know what I find in there. Hopefully yall saved the day