I'm going crazy here I can't figure this out.

My bike will only start with a shot of starting fluid and then of course it immediately dies. I cleaned the carbs, checked spark for all cylinders and got new plugs. Gas is flowing good to the carbs. I changed the gas as it had been sitting all winter.

I noticed when I was trying to start it that air was puffing out of the carbs. This isn't normal is it? Is this a timing issue? It has been backfiring and popping back through the carbs too.

Any help that any of you can offer would be so much appreciated.

 

Look at the bold above.

You didn't say but I'm assuming you did not put some kind of stabilizer in the gas that sat in the bike all winter.

Is that right?

(BTW...it's best to drain all fuel from everywhere on the bike if you are going to store it.)

Anyway...the reason the bike starts with starting fluid...is because that fluid is easily flammable...much lower flash point than gas.

You have gummed up carbs bud.

That means you need to take them apart and have them cleaned...jets..bowls...everything...

That would be my first guess...

 

Thanks for your help.

Like an idiot I didn't use any kind of stabilizer.

I took the carbs off of the bike and took the float and choke assemblys apart and sprayed them really good with carb cleaner and that didn't help at all. There wasn't much in the way of varnish but there was what looked like rust from the tank.

If anyone has any idea about the puffs of air coming out of the carbs I would appreciate. Also, the vacuum hose that comes from the #1 cylinder is puffing out air instead of having suction. I'm thinking this shouldn't be happening and that the intake valves are opening on the up stroke instead of on the down but I'm not an expert.

 

I just went through a whole routine trying to get my 94 F2 to start. I tried draining the old gas out of the tank, draining the bowls on the carbs, pulling the plugs and cleaning them with the air compressor. All it would do is pop a little and then backfire after cranking for awhile. The plugs were wet when I pulled them and they are brand new. I put them in in December because I was bored. anyway, I eventually gave my cousin a call and what he ended up doing was burning anything off the ends of the plugs with a propane torch for a bit. dropped them back in, bam, it starts.
thats just my experience. I'm reasonably sure that the reason it wouldn't start before was that it was flooding out and thats what ultimately would cause the backfire. And that was what was fouling up the plugs. Not sure if that'll help you but thats my story.
good luck

 

i know this is an OLD thread... but same problem
i finally got another F2 after my horrific accident on my last one 9 months ago, i just picked this one up yesterday, it ran at the guys house but it had a very mild missfire every now and then, fired it up this morning no problem, then in the afternoon after work to fire it up and all it would do is backfire. cleaned out the plugs, new gas. and it shows a tiny bit of life when used with starting fluid.
i guess im gonna clean out the carbs and clean everything up today and pray for the best haha

 

Check the battery is my guess.

 

And the ignition leads are on the right sprak plugs ?