Bike Acting Wierd

[alva219]

I went out for a ride to Danville this evening and on my way back my bike started acting funny. Whenever i would be taking off from a stop, it would get up to speed in first gear, and then begin sputtering and stallling until i revved it more and shift. For a while while i was riding i thought i was just going a bad job with the clutch, but when i pulled into my garage and just let it idle in neutral so i could take a look at it, i noticed that it would make a few revolutions with the engine, and then it seemed as though it would skip a beat. I put my hand next to the exhaust and felt like it was missing a stroke or something. Not sure what it is whether it is bad fuel or if one of my spark plugs is dead. If anyone is a mechanic or has had this happen to them I would love to hear some ideas on how to fix it. I ride a Honda cbr f4 btw.

 

[altomista]

When's the last time you had a valve check?

BTW, this belongs in the Garage section.

 

[DaineseDan]

Need more info. Could be a thousand different things. What RPM is it cutting out at. Is the bike cold or hot when exhibiting symptoms? Is the bike stock, and if not what mods? Is it doing it consistently or intermitantaly and under what conditions? Is it only missing at idle, or under load as well? Does it seem to clear out when revved?

Any details you can think of will help, even if you think they are trivial.

 

[alva219]

sry i know i should have posted in the garage section, but i just know that more ppl look in this one. The bike smoothes out when i rev it past 2000. It only sputters in 1st gear when its under load just after im getting out of the friction zone at aroun 5-10 mile/hr. The bike is stock, and i just got it 2 weeks ago but i have ridden about 200 miles on it with no problems. i guess it could be valve's but my mind is still pretty set on it being a spark plug. Iono. any suggestions are welcome

 

[-Baker-]

I would also put a volt meter to the battery and test the volts coming off at idle and rev it to 2k.....post voltage.

Is that ur bike in you avatar? It looks like a Honda...your problem sounds like a Honda too...lol j/k

 

[DaineseDan]

Very unlikely it's valves. Start with electrical. Check for spark on all of your plugs, and check the wires and coils with a voltmeter.. Your bike is also notorious for going through regulator/rectifiers. Have you had any problems with your battery keeping a charge?

I don't remember from your avatar, but do you have an F4 or F4I. F4I's periodically have injectors go bad, but it is rare.

Do you ever notice a slight grinding/rattling sound at idle, especially when cold?

 

[alva219]

i've gota an f4 as i said in my first post. Im going to check the plugs tomorrow, and get some carb cleaner for my fuel. I'll let you know how the volt meter reads. I havent had a problem with the battery so far. and i know it cant be a bad injector cause i dont have any haha. thanks for your suggestions

 

[T-1 Thunder]

Get an F4i. Problem solved, no more synch with carbs required.
No more of all the crap associated with carbs, period.

But since you are stuck with it - check them one by one by pulling them plugs.

 

[Diezel]

Sounds like time for a Carb cleaning / Synch *assuming it's not an F4i.

 

[alva219]

no f4i here. too much of a noob and not enough dough. haha i'll stick with wut i got and clean her up some.

 

[bte320]

take it to Rob at Evolution Suspension. guy saved me thousands last time I was there.

 

[DaineseDan]

DO NOT USE ANY CARB CLEANING ADDITIVE WHATSOEVER!!!!!

Unless you want to completely rebuild your carbs. Those additives are developed for cars that don't use all the soft little rubber o-rings and plastic bits that motorcycles carbs do. They will destroy those bits and leave you with a very hefty bill for a carb clean/rebuild.

Try just draining the float bowls fist. Any large debris will settle in the bottom of the bowl. There will be a good sized phillips or allen on the side of the carb. Just back it out on each carb, and fuel will flow out the overflow tubes which should exit near the front portion of your swingarm.