I just go a 96 F3 a couple of days ago. I bought it two hours away from where I live and it ran fine on the ride back up. I put about another 150-175 miles on it, but I ran into problems today on a long trip. After about 100 miles, I had been cruising at 65-70 for the past 15 min. When I slowed down at a stop sign and proceeded to accelerate, it bogged and would hold its idle. I got it running, but it wasn't really responding to the throttle. I went about another mile and it shut down completely (going about 80) and would respond to the throttle at all. Bottom line: will start, but only when choked to the max and will idle at about 1 1/2 rpms. When the throttle is engaged, the bike dies. I suspect it may be the fuel pump/relay?

ps - I race motorcross, but am very new to street bikes. I don't know if y'all have ever interacted with four-stroke dirtbikes, but the CBR has very similar symptoms to a very cold and struggling old 4-stroke. It'll weakly hold it's idle, but won't engaged the throttle.

Let me know what you think...

 

Going through the exact same thing at the moment and thought id share what to try. Start the bike, let it run for a min and carefully feel the header pipes, see if one or more is cool enough to touch while the others are hot. Bypass the fuel pump completely, just run the fuel line from the tank directly to the " T " at the carbs and see if that helps. If it does you have a fuel pump or relay issue. Good luck and keep us posted on your results.

Blake

 

That's good advice... I'll give that a try asap.

So I've been calling up dealerships around the country and a lot of the honda techs are thinking (from my description) that it may be the carbs. Here's their logic:

- If it was the fuel pump it would do one of two things (1) either fade out (which it didn't) or (2) completely go bad in which case it wouldn't start at all (which it does)
- If the carbs are dirty, it'll start, but only when choked due to the fact that this by passes the carbs and sends the fuel directly to the cylinders.

But this is what I don't understand... how do the carbs just suddenly get dirty? I though this was more of a gradual thing. Could it be that there's just a piece of trash that got caught in the carbs and is blocking fuel flow and if that's the case, I've got four carbs, and I'm not getting any throttle.

Let me know what y'all think.

 

Common problems on just bought bikes. )) Just do some maintenance. Carbs, vents, plugs, check fuel pump, fuel relay etc. And you will be fine. The most common problem is just dirt that stuck in some fuel/air line or filter.

 

I am having the same problems only my exhaust is really smoky.

 

I just fixed mine, here is what I did, replaced the fuel filter, blew out the fuel pump and gas lines with compressed air, pulled off the air filters and poured a little bit of sea foam into each carb and it started right up without choke, and revved just fine. Hope this helps.

 

It didn't suddenly get dirty. It was prolly already gunked up and riding it loosened the gunk, letting it into the fuel system.

Check / change the fuel filter (mine was completely blocked with the engine sucking gas through it). Check the condition of your spark plugs (mine had detonated). You can try starting with Seafoam. Might clean things out enough to get her going. It will not take the place of a thorough cleaning tho. I ran 2 cans of Seafoam through my bike and still had clogged jets.

If it's still acting up holla back. Depending on your skill / tolerance for insanity, pulling the carbs will be either your first or last option. Try to make it last, checking that the fuel lines aren't blocked / the plugs aren't fouled / and gas is getting into the float bowls.

 

hey great news i i took the bike apart cleaned the fuel lines , with compressed air , an cleaned the fuel filter , dumped some sea foam down the carbs and fired it up and now its running great , it smoked for a little while from the sea foam but problem solved thanks guys for the input . i hope this could help anyone else who may be having similar problems only took about 1.5 hour.

 

Make sure your vent tube for your gas tank isnt clogged. If its clogged it will start to put a vacuum in the tank and will shut the bike down. You can either take the tube off and check it or if you ride the bike til it shuts down immediately open the gas cap and see if you can hear air get sucked into the tank.