[myfirstcbr600]

1998 CBR 600 F3
Bike was garaged for 5 years, in really good shape at 10k miles.
removed the carbs, cleaned the bowls and jets.
air filter looks good.
replaced the spark plugs (gapped), oil & filter, coolant.
filled with gas mixed with some sea foam.
wouldn't start (turns over, but no firing)
bypassed gas pump and raised height of gas tank.
fluid flows freely out of the tank.
Only fires if choke is full and I spray starter fluid into the front intake
revs high, then idles for a while, then dies.

acts like gas isn't getting into the carbs at all. Is there an easy way to check without taking off the carbs again.

 

[Jetpilot07]

sounds like you might still have some blockage somewhere in the fuel system. or could be low on compression.

 

[RICK-ITFC]

take plug caps off, turn bike over if plugs are wet through fuel then they is getting fuel.but does sound like fuel not getting through, or look the other way you might be getting to much air, check seals arnt perrished and letting air in..

 

[myfirstcbr600]

a guy at work said that using a tank of racing fuel will clean out clogged jets... any thoughts?

 

[kuroshio]

Doubtful since your carbs wouldn't be getting enough of the race fuel to clean it out.

Sounds like a fuel delivery issue going by what you're sayin. You might need to go back into the carbs and clean them some more.

 

[ucfmotorcycle1]

Could be fuel pump. Not sure what type of fuel delivery on the F3 but it def sounds like its not getting gas. And I would not run it too much on that starting fluid. A better solution is to just put fresh gas in a spray bottle.

 

[kuroshio]

Could be fuel pump. Not sure what type of fuel delivery on the F3 but it def sounds like its not getting gas. And I would not run it too much on that starting fluid. A better solution is to just put fresh gas in a spray bottle.

Sounds like he already bypassed the pump and did a gravity feed.

I had cleaned my carbs 3 times before I was completely sure they were clean. On the 3rd try I still found clogs in the system. I also soaked everything in carb cleaner that was safe to do so and took compressed air to anything that had a hole.

The fuel path through the carbs is still some of a mystery to me. But it sounds like not enough fuel is getting through his carbs to start the engine. Another possible is the pilot jets are set wrong

 

[alterego]

to do a quick ck to see if the fuel is getting to your carbs from the tank losen the bowl nuts( drain screw) let the fuel that is in there if and drain out then turn the bike on if you are getting fuel there then your problem is father on in the system but still might not be the carbs themselves take a squirt bottle with some gas and spray around the carb boots see if the bike starts that would mean you did not seat the carbs completely and you need to push them the rest of the way down in the boots.
AS for the race fuel you will be wasting your time and money and if the bike does start on it depending on the grade of fuel you use it could cause predetonation and burn a hole in the top of your piston before you know it!

If you find it is still your carbs take them off and disassemble them find a carb shop around where you live that has a sonic cleaner and let them clean them in that

hope that will help you some

 

[zero937]

i would adjust the flotes in the carbs sometimes they get miss aliened and dont let enough fuel by

 

[kuroshio]

i would adjust the flotes in the carbs sometimes they get miss aliened and dont let enough fuel by

F3 float height isn't adjustable. It's either right or replace the float

 

[zero937]

relly i thought it was like a dirt bike carb just bend the little tab but i guess i was wrong

 

[kuroshio]

relly i thought it was like a dirt bike carb just bend the little tab but i guess i was wrong

It's not designed to be adjustable. Doesn't mean someone can't find a way to adjust it

Going from the experience with my carbs if fuel is getting through the carbs, she'll start. It may run like crap and / or eventually stall out. but she'll start. The needle and pilot jets were clogged, fuel pump dead and the fuel filter completely stuffed up (running water wouldn't pass through it at all). But she still started and ran.

And I dunno wth happened to the plugs as you can see here. But she ran

 

[zero937]

this is what i mean by adjust the little copper tab where the arrow ponts at is the one im talking about just bent it up or down to make adjustments it regulates how much fule comes in and goes out
http://i195.photobucket.com/albums/z216/zero937/floatlevel1-1.jpg

 

[kuroshio]

isn't one on the F3 carbs. The float is a single plastic component sitting on a dowel. So long as the float moves freely, not getting stuck closed, you should be good enough to start the bike. F3 carbs are pretty sturdy, letting the bike run even when signifcantly out of whack (trust me). Will prolly start with 2 of the carbs completely dead (bad coil pack)

Someone suggested cranking the bike and then checking to see if the plugs are wet with fuel. I'm betting they aren't. Sounds like fuel isn't getting thru the carbs.

The gravity feed eliminates the pump. And others, including myself, have gotten the bike running with the pump installed but out of commission. He's gotten it running using starting fluid and full choke. But eventually it stalls out. That makes it sounds like it's not getting enough fuel to start the bike. And bypassing the carbs with starting fluid has the engine sucking fuel past whatever's blocking it till it starves out.