Hey Guys,

my F2 is not staying on. When I can get the bike to start with the choke fully opened, it will run for about 5 minutes and then the engine will came to a stop. When trying to start it back up, enging just cranks over without any spark. What could be the cause for this, and what are the key things to check. I am trying to fix myself to avoid taking it to the shop (as they will hold it for weeks on end)
Please help.
THanks,
Ray

 

hmm should try searching the forums but...
one cause may be no gas trust me ive been like why the hell isnt it starting only to find no more gas

 

1. no fuel to carbs

2. engine flooded with fuel

3. no spark at plug, ignition system faulty

4. clogged air cleaner

5. intake air leak

6. improper choke operation

7. imporper throttle operation

8. faulty fuel pump

9. faulty fuel pump relay

 

I have been looking at the other thread where theguy is having a bike not starting issue. Thanks for the key pointers, will check them all to see if it works, if not, I will be back.
Thanks

 

Stupid question...you are switching the fuel petcock down, correct? Down is the main tank, middle is off and up is the reserve tank.

You say after it's been running for about 5 minutes, then it just cranks without a spark. Did you actually pull the plugs and check for a spark? I'm guessing you mean that it does turn over after it's been warmed up.

When starting the bike with the choke on, it enriches the fuel air mixture. If it happens to be warm out when you start it, you will have to cut back on the choke almost immediately to keep the engine from idling too far about 2000 rpm. For instance, if I'm at work, and my F2 is sitting in the sun on a 70 degree day, I will start it with full choke and almost immediately cut back to keep the idling at a reasonable rate. Soon after I shut the choke off completely. If you get it to run for about 5 minutes and this occurs each time after the engine is cooled, then I would say that the jets in your carbs are clogged.

One thing that you can do, is try placing Seafoam in the tank. Let it sit a little and then try starting it. I don't know how well the stuff works on clogged jets, I do know that after a winter storage, it allowed me to start my F2 without a hitch. If that doesn't work, then I would pull the carbs. If there's gas in the bowls then I'd say the flow from the tank isn't the issue. I would then give the carbs a thorough cleaning and make sure the 3 sets of jets are clear. There's a very good walk-through in the How-To section concerning cleaning the carbs BUT it doesn't detail the jet cleaning stage.

After you get it all back together, balance the carbs and adjust the pilot screws as recommended in the service manual. Speaking of service manual; The manual will have a lot of troubleshooting steps to go through to diagnose the problem. There's a few posts on CBRForum that link to the manual.

Worse comes to worse, take it to a mechanic.

Best of luck.
Nick

 

Just got two of my non-starting problems fixed by putting in new sparkplugs. I think I had some bad gas that fouled them possibly. Both run nicely now. Start with the cheapest/easiest stuff first.

 

Will do, I will try changing the spark plugs, and then taking a look at what has been suggested. Thanks Guys, will keep u posted.

 

alright guys,
so I was getting ready to check the items listed above, but before I did, I started the bike to see if it would start, and it did. It was a warm day, so as soon as the bike kicked on, I cut the choke off, and held the throtlle for a while and let go. The bike stayed on. I was kind of scared to ride as I didn't want to be stranded on the road way, but I did anyway, and road about 10 mile in regular traffic and she held up very well. I know there has to be something wrong because as this tread started, I mentioned that it would run, then stop, then it wouldn't start for at least a day or two, and then when it comes on, it rides ok for a few days, and then it will start the whole process of not starting again. I will replace the plugs tomorrow and see if that would take care of that problem.

If anyone know's why it does this please share.
Thanks
Ray

 

oh, and the bike did have good fresh gas, 91 octane the day prior to it not starting.

 

You might have had fresh gas in the tank...but did your carbs sit with gas in them for the winter? that is a sure fire way to get your jets clogged (plus gunking up the bowls and float). I still say add some seafoam for now. Help clean anything remaining out. Oh, btw, F2s use 87 Octane. Your just wasting your money getting the higher grade crap.