I just recently purchased this bike as an upgrade.. And obviously I am not the smartest!! So.... I rode for almost a week and was not aware that the choke lever position for OFF was up.. and not down.. I was riding with the choke wide open.. Rookie mistake.. now I can ride for about a mile and it will die out on me.. I will be cruising and all of a sudden it loses power, bogs down and dies out.. It will start right back up after letting it sit for a few mins.. I can then ride for about another mile and it happens again.. and now when i start it a loud ticking noise comes from the motor and lasts about 2 or 3 mins and then stops.. can anyone at all please let me know how bad i have messed something up or the steps i can take to get it running great again.. it has 32k miles and ran awesome until now!! thank you to everyone who reads and responds!!
94 CBR F2 problems!! Please help!!
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The good news is you most likely haven't messed it up badly. Riding with the choke open causes it to run rich, which means unburnt fuel fouls up the spark plugs. There is a good chance that is the extent of the issue. It's possible there's more gunked up on the exhaust side of things, but I wouldn't worry about that yet.
So, to fix it you need to pull the plugs and at a minimum, clean them. Myself, I'd go ahead and put fresh ones in. Won't cost much and depending on the miles, it could be due. While you are at it, I would go ahead and change the oil, air filter, and coolant. You'll most likely want to pull the lower fairing off anyway to make the spark plugs easier to get to, and the coolant, oil, and oil filter are easy to do at that point. May as well remove the gas tank and do the air filter while you're at it.
After that, I'd run a tank of gas (my shop manual says F2s didn't need 91 octane, mid grade 89 should be fine) with one ounce per gallon of sea foam in it and you should be right as rain.
So, to fix it you need to pull the plugs and at a minimum, clean them. Myself, I'd go ahead and put fresh ones in. Won't cost much and depending on the miles, it could be due. While you are at it, I would go ahead and change the oil, air filter, and coolant. You'll most likely want to pull the lower fairing off anyway to make the spark plugs easier to get to, and the coolant, oil, and oil filter are easy to do at that point. May as well remove the gas tank and do the air filter while you're at it.
After that, I'd run a tank of gas (my shop manual says F2s didn't need 91 octane, mid grade 89 should be fine) with one ounce per gallon of sea foam in it and you should be right as rain.
Thank you Rob! The guy I bought it from lives down the street from me.. We changed the oil, coolant, and all filters the day I bought it from him.. as well as all new plugs and wires.. I have pulled all the plugs and they had burnt oil around the base and one was completely bent over. I think riding it for almost a week with the choke on pretty much did them in to say the least. I fixed the gap they are all between .03 and .04 inches now, sanded them lightly with some sand paper, used a little brake cleaner and a wire brush, they look brand new again. But now I am having a hell of a time getting them back in.. I turn them to tighten them and it seems as if they are not catching and just turning forever.. Any tips?? I would like to avoid taking the radiator off and the fairings if possible. I have skinny arms so they fit in pretty easy.
And it has always had Premium gas ran through it so I will continue to run that in it.. And I have a can of sea foam in the garage as well.. Thats what I was going to do originally, the spark plugs being the problem didnt even cross my mind.. Thanks again! It really helped!!
When I change mine I just use a spark plug socket with an extension on it. The spark plug socket has a rubber boot inside it to hold the plug snug while it isn't screwed into the threads. That lets me lower it into the hole and I get them started just by turning the extender with my fingers. Make sure you use anti-seize on them and don't over tighten. You should be set!
Edit: One other thing I do on the plugs, I'll usually turn them 1/4 - 1/2 turn counter clockwise before switching to clockwise to screw them in. It seems like backing them up helps the threads line up and bite cleaner to me.
Edit: One other thing I do on the plugs, I'll usually turn them 1/4 - 1/2 turn counter clockwise before switching to clockwise to screw them in. It seems like backing them up helps the threads line up and bite cleaner to me.
I have changed the plugs and got them back in.. Still dies on me after about a mile.. Do you think it could be the battery?? The battery was bought back in 2011.. I am going to charge it over night.. if the battery is shot could that possibly be my problem?
Seems unlikely it is the battery, but it could be the charging system. Test that once the battery is charged and make sure it's putting out enough power when running.
Could also be that the plugs, while now clean, are damaged. Might be worth trying a new set if the charging system shows OK before checking into other areas.
Also, the F2 uses a vacuum petcock, which has one fuel line that sends gas to the carbs and one vacuum hose that goes to a port on the left most carb, on it's lower left side. The vacuum from the carb activates a diaphragm in the petcock that only lets gas flow when the bike is running. It's a pretty cool idea, but in practice it's a royal pain in the ass. Could be you pulled that hose off getting to the plugs and the lack of suction is preventing fuel from getting to the carbs consistently. You'll have to pull the lower left body panel to check it though.
Could also be that the plugs, while now clean, are damaged. Might be worth trying a new set if the charging system shows OK before checking into other areas.
Also, the F2 uses a vacuum petcock, which has one fuel line that sends gas to the carbs and one vacuum hose that goes to a port on the left most carb, on it's lower left side. The vacuum from the carb activates a diaphragm in the petcock that only lets gas flow when the bike is running. It's a pretty cool idea, but in practice it's a royal pain in the ass. Could be you pulled that hose off getting to the plugs and the lack of suction is preventing fuel from getting to the carbs consistently. You'll have to pull the lower left body panel to check it though.
Also, you may need to let it idle for a bit and get nice and warm before you go riding. And while riding, you're likely to need to nurse it with the throttle for 30 -50 miles (about a gallon of gas) while the sea foam, heat, and combustion break up the carbon and gunk from running it rich. Your intake and exhaust valves could be gummed up a bit, and you want to try and run it without the choke on to get a clean burn and generate enough heat and suction to clean them out. Try and take it out on a road with few stops that allows you to keep the engine revving fuel and air through for lengthy periods of time. You want to avoid stop and go traffic and let the sea foam and clean plugs do their job on the rest of the intake and exhaust.
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this particular model of motorcycle also has a notorious problem of the pre bent fuel line that goes into the carburetors collapsing with heat. if you or the previous owner ever pulled the fuel line of when you took the gas tank off and tore the very end of the fuel line attempting to get it off the carburetors it was probably just shortened because that's a common idea on how to fix your problem. in all actuality it creates a whole new problem because the fuel line is so formed that the new angle because of the shorter line create a collapse when it gets warm. I have never been able to substitute the factory fuel line because of this I always just buy a new one. so you can probably make yourself a small fuel cell and see if the bike is idols with the gas tank of running fuel into the carburetors from your fuel cell if it doesn't die after several minutes idoling its a strong indicator that your fuel line is the culpritor at the very least something between the gas tank and the carburetors
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The F2 like many a Honda has suffered from charging problems.
You may want to look at the regulator and the starter solenoid for fried wires.
You may want to look at the regulator and the starter solenoid for fried wires.
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