Help! Thought I'd fixed it! UGH!

[Heater]

:banghead: Hey. I have a 95 F3 that started hesitating while in gear. Didn't matter which gear I was in, I felt power draining. When I would throttle, it would hesitate again for a sec, then catch. Well, I changed the oil, put a new oil filter in, and cleaned the air filter. The carbs were pretty clean, but I wiped them out anyways. It's been running like a champ for about a week now, then today, the hesitation started. My guess is it's the air filter, but can it get that dirty that quick? It's a K&N that I just rinse out real well and dry. New battery put in last year, fires up just fine, doesn't seem electrical. Full tank of gas, so don't even go there! Any other ideas or tips would be much appreciated!

[Devaclis]

Fuel filter or clutch.

What oil are you using? does it happen when the bike is cold, hot, been sitting, or all the time?

[dapper]

Vapor lock?
If the fuel was fresh, (cold between the legs) than vapor lock might not be the issue.

Proper jetting?

[salsashark]

Idles alright, but when you roll the throttle it bogs down for a second then revs up?

Sound like a sticking carb. My T-dub was doing the same thing.

Try running some sea foam through the carbs and gas and see if that helps.

[Heater]

Vaccum on carbs was good, didn't see or hear any sticking. Fuel was from yesterday and I have ridden 40+ miles since. It does it when it's warmed up and I've been riding for a bit. I use 10w 40 4T oil. I've always used premium gas and have no idea about the fuel filter. I'll look into it. I just don't understand why it was fine for a week and is now getting cranky again!

[Devaclis]

Fuel filter

This bikes have a gas cap designed to prevent vapor lock. It can still happen but I would think that would be far down the list of possibilities.

[rybo]

Fuel filter is a good place to start.

The condition you describe is a "lean" condition, which would indicate not enough fuel / too much air in the ratio, so air filter is unlikely.

My first move would be to change the fuel filter. Less than $15 in parts and 1/2 hour of your time.

From there I'd look to the carbs themselves. Clogged jet is a possibility. Rolling on the throttle you use the "pilot" or "slow" jet and when you open the throttle further you get to the "main" jet. It is possible that the pilot jet is clogged and causing some fuel starvation and when you come onto the main jet you are getting the fuel you need.

Finally it may be a stuck float or a bad float seal.

Best of luck!

Scott

[niko303]

Hey I sorry about the bike but I really think it is your carbs,,,could be your jetting which could be your hesitation- a sticking problem with your floats the needles have a gasket on each of them ,one might look like a flat tire and need to be replaced,this could cause the sticking hense hesitation ,if this is the problem needs fixed.Most bikes after some time/if at some point sit without being ran/started will have this problem gaskets /seals get dry and go bad ..Once you sort through this its all good,but it does suck in the process..So do the basics first,,new gas premium,run some carb cleaner through &through/sea foam///One more thing might make sense when gasket get warm they expand and seal,,,so think if I have a bad one that isnt happening,,which could lead to your troubles.

[longrider]

:banghead: It's a K&N that I just rinse out real well and dry.

This part of your post caught my eye. Do you oil the filter after you clean it? A K&N needs to be oiled with K&N filter oil to work properly plus a dry filter will flow a lot more air which would result in a lean condition.

[RXGhost]

If you can smell your exhaust if it smells a little like gas, check your float bowl fill needle, the rubber tip on these like to build up a very thin clear coat of gelled fuel that you can scratch off with your nail don't use anything like a knife and don't apply to much pressure so you don't pull the rubber tip out of the needle, some times you need to clean them out 2-3 times with these f3's they are a little touchy

[Flyin Hawaiian]

I recently had the same problem. (8 months ago) I thought it was the air filter,then the fuel filter, then the carbs. None of the above!

Have you had any electrical issues? Try checking your regulator which is prone to go out on the F3's. You can test it with a multimeter. I have some literature on how to do it yourself. Will post when I locate it. Good Luck.

[Heater]

Thanks! I have some ideas and will try to tackle the bike again this week. Probably start cheap with the fuel filter, then work my way to the carbs and possible heading to OTD for them to check it out and possibly re-jet.

[Heater]

This part of your post caught my eye. Do you oil the filter after you clean it? A K&N needs to be oiled with K&N filter oil to work properly plus a dry filter will flow a lot more air which would result in a lean condition.

Didn't oil it. Had no idea I needed to! Was just told to use water and wash real well, let air dry before installing again.

[Tipys]

This part of your post caught my eye. Do you oil the filter after you clean it? A K&N needs to be oiled with K&N filter oil to work properly plus a dry filter will flow a lot more air which would result in a lean condition.


HHMMMM never heard of that before. Being a car guy I always see the people that over oil them then the MAS or MAP sensors get covered in oil and dont like to work right. But this bike is carb'd so to much oil wouldnt be a problem.

[Tipys]

Didn't oil it. Had no idea I needed to! Was just told to use water and wash real well, let air dry before installing again.


K and N has an oil that you buy to put in them.



With stories of people putting energy drinks in there gas tanks and letting friends drill throw there ECM. I would hate to hear a story of 10-30 being used on an air filter.

[Jim_Vess]

Didn't oil it. Had no idea I needed to! Was just told to use water and wash real well, let air dry before installing again.

You definitely need to oil it after you clean it.

You can buy K&N filter oil at most auto parts stores. Just get the small spray can, it will be more than enough to oil the filter a few times.

[Heater]

I'm going to pick up an oil filter and hopefully the K&N oil at OTD Thursday or Friday. Now the big question! I don't have a garage or a ton of tools. Would anyone be willing to help/show me how to change the fuel filter and properly oil the air filter. I know it's a lot to ask. I will buy beer, wine, whatever and can give you a little money for "shop time", just not a lot. I work 2 jobs for a reason! LOL! The bike is rideable for now and I live in Aurora. Working on it at my apartment is a no no, so ideally I could come to you. Again, I know it's a huge favor, but the weather's beautiful and riding is how I de-stress and I'm starting to FREAK out just a tad!! Thanks again for everything.

[salsashark]

Do you have a shop manual or a Chiltons/Haynes for the bike? I've got a garage and I'm sure we can figure it out.

[Kim-n-Dean]

I'm going to pick up an oil filter and hopefully the K&N oil at OTD Thursday or Friday. Now the big question! I don't have a garage or a ton of tools. Would anyone be willing to help/show me how to change the fuel filter and properly oil the air filter. I know it's a lot to ask. I will buy beer, wine, whatever and can give you a little money for "shop time", just not a lot. I work 2 jobs for a reason! LOL! The bike is rideable for now and I live in Aurora. Working on it at my apartment is a no no, so ideally I could come to you. Again, I know it's a huge favor, but the weather's beautiful and riding is how I de-stress and I'm starting to FREAK out just a tad!! Thanks again for everything.I doubt it's the fuel filter. If the filter was causing the starvation, it would only get worse as the RPM's increase and try to pull more fuel through the filter. Dirty jets or sticky float, something in the carb most likely. I'm in Aurora if you still need a place.

[whitebrad]

o2 sensor on that one?

i can't remember with the years... f-3 i thought had it...

hmmm, if it did, there is that whole line between 02 sensor and ecu that can lean it out really badly...

[rybo]

I doubt it's the fuel filter. If the filter was causing the starvation, it would only get worse as the RPM's increase and try to pull more fuel through the filter. Dirty jets or sticky float, something in the carb most likely. I'm in Aurora if you still need a place.

Dean is a great mechanic and a good guy! Highly recommend working with him.


o2 sensor on that one?

i can't remember with the years... f-3 i thought had it...

hmmm, if it did, there is that whole line between 02 sensor and ecu that can lean it out really badly...

F3 is carbs, so no O2 sensor and no way for the ECU to adjust mixture.

[whitebrad]

f-4 went to injection? i thought f-3...

man, leaning out on carbs is a pain in the arse...

one thing to check, at high revs are you getting any power drainage?

[Kim-n-Dean]

Dean is a great mechanic and a good guy! Highly recommend working with him.Why thank you,Scott! I'm going to have to hire you as my PR guy, some day!

My quad and dirt bike both had the same symptoms when they were new. Took the carbs apart and cleaned them, also installed fuel filters. (Dirt machines don't come with them) And never had the problem again.

[rybo]

f-4 went to injection? i thought f-3...



Not just F4, but an even later bike the F4i.

[whitebrad]

Not just F4, but an even later bike the F4i.

dayum, now that you say that, i remember, and feel dumb... stupid letters after numbers being a dead reminder...

in my defense, i do ride a pasta rocket, and all previous rice thought gets eaten

ffffffkin rotax.... mmmmmmm

[supertune]

i just saw this thread about your CBR F3. I know this bike well.
That bike had an early generation "ram air" system that if there are any problems could generate a throttle response problem.
If you didn't make any changes and it started running poorly it may be something in the fuel or an idle or pilot jet that needs to be cleaned.

Call our shop. (# is below)
mike

[Heater]

I doubt it's the fuel filter. If the filter was causing the starvation, it would only get worse as the RPM's increase and try to pull more fuel through the filter. Dirty jets or sticky float, something in the carb most likely. I'm in Aurora if you still need a place.

Are you pretty familiar with the F3 design? I haven't been able to get ahold of a Chiltons yet. I'd love to just save everyone's time and frustration and have someone who is familiar tackle it with me.
The fact that other's are reccomending you is pretty heartening.

[RXGhost]

If you need some help up north just let me know I got all the tools you need at that shop and house
but I am a bit of a ride north but the option is there if need be

[McVaaahhh]

There's microfiche on ronayers.com or bikebandit.com that shows you where everything is.

Also, check out this thread down a bit and you can download the manual.

http://www.cosportbikeclub.org/forums/showthread.php?t=858&page=4


You have to pull the tank, and the fuel filter is right under it. :up:

[Kim-n-Dean]

Are you pretty familiar with the F3 design? I haven't been able to get ahold of a Chiltons yet. I'd love to just save everyone's time and frustration and have someone who is familiar tackle it with me.
The fact that other's are reccomending you is pretty heartening.Never worked on an F3 before, that I recall. I don't really think that matters, though. They all have the carbs in the same place. However, a shop that works on tons of bikes might know of a specific problem with that bike and could possibly go straight to the problem.

I would first look for anything obvious, then check all the wiring to make sure it's not a bad connection or plug. Then, it's pull the carbs and clean them. Pretty simple stuff. It can take time, though.

[Heater]

There's microfiche on ronayers.com or bikebandit.com that shows you where everything is.

Also, check out this thread down a bit and you can download the manual.

http://www.cosportbikeclub.org/forums/showthread.php?t=858&page=4


You have to pull the tank, and the fuel filter is right under it. :up:

So, am I being "special"? I think that the link has expired and googling free, downloadable manuals isn't working out so well. I will need to call around, or by some miracle see if a library has one. Thanks though.

[ebb]

Check your fuel pump, they do strange things I had like issues. One minute the bike would start and run perfect another day it would act like it was starving for fuel. Pump is easy to get to, pull the fuel line going to the carbs give the starter switch a quick push make sure you cover your fuel line with an old towel so you dont spray or leak fuel all over. You will hear the pump engauge only when the starter is quickly pressed. If the towel is wet you are probably getting ample fuel and it may be ok. The fuel pumps have a little diaphram that sticks or wears out, works or not depending on fuel pressure the pump its self and heat off the engine. Mine acted strange for a couple months, now no problems knock on wood.
good luck:banghead:

[Heater]

Worked on it this weekend, hopefully fixed it. We will see.
Carbs re-jetted. New fuel filter. Coolant drain and change.
Running like a dream so far. Fingers crossed.

[Filo]

Hey, I used to have an F3 race bike and had the manual on a CD and on my computer. Let me look around the house and see if I still have it. If so, its yours. It was scanned off of a copier, so it isn't perfect but it works.

[Heater]

Hey, I used to have an F3 race bike and had the manual on a CD and on my computer. Let me look around the house and see if I still have it. If so, its yours. It was scanned off of a copier, so it isn't perfect but it works.

Hey thanks a ton, but I already got one. I appreciate it though!