Alright. I've been working on my CBR600 F3. I have brand new plugs, a fairly clean air filter, and just got the carbs synched up along with the air/fuel mixture adjusted. I also just replaced the Fuel Filter and have new 93octane gas in it.

But if I run down the street and don't stay at 7,000rpms+ the motor dies out. At first I thought it was stuttering but now I'm sure it dies and is coming and going back to life. It only does it while riding.

Now the guy who worked on my bike said it looked like my rubber boots(Think that's what he said) looked pretty dry that are on my Carbs. And he believes it might be sucking in extra air. And I'm thinking that might be it because it only stalls out when running around 30-40mph plus unless I'm hard in the gas and up in the high RPMs. At low speeds it revs just fine and has no problem running. The idle does vary some though.

Here is some video I took. Around 43seconds I put it in either 3rd or 4th while running. It sits at 4k and then when I pull in the clutch the RPMs drop to zero. When I put it back in first it starts up again. But it won't start while cruising and just hitting the ignition.
http://www.youtube.com/watch?v=9MbqhhQdD34

Let me know what you think.

 

"Free -revving " the bike like that before it's up to temp will cold seize the motor.

Fire up the bike,and spray brake cleaner or starting fluid on the carb boots.If your idle goes up,your boots are leaking.

 

As84 - Battery sounds weak on it - cranking slowed significantly while rolling... - Though that doesn't necesarily explain the stall initially - Could a faulty regulator draw enough voltage to stall the engine? - Then would it crank some to try to return to life, but the starter draws enough current that you aren't getting good enough spark to fire up - but bump starting it doesn't take any juice for the starter? - Can adding any electrical load encourage the stall earlier? - IE flip on the high beams...

kj - Interesting thought on the "Free Reving thing" - Our MSF class instructor had us revving the HELL out of our little Kawasaki's to warm them up - choke on - no tach - she basically said rev them to the limiter. - I usually just start my F4iand let it idle in the driveway while I gear up. (Nice secure ND area here though.)

 

I know Free Reving isn't good. Which I took it to a shop and had the last guy to work on my bike view the video. He cringed when he saw me free reving. He stated that it's hard on motors and messes with the valves. I just did it so people could see the motor snap/lack of snap. I had the bike running for about 5minutes if that helps(With part of it on choke).

I ordered the rubber boots because after speaking to the mechanic he said when he observed my carbs earlier that he felt they looked so bad that if he did remove the carbs to clean he'd be calling me to tell me I have to order those. Suprisingly the 4boots weren't too expensive or as expensive as I thought they'd be ($11 each). I figured I'd go ahead and replace them. One thing I found out about Honda is they love their parts and have a price to prove it.

I'll probably take the carbs off fairly soon and just go through them. But I doubt they are clogged because if so I think the Idlerneedle would be clogged first. Which the bike seems to idle fine.

When I do get the boots and the carbs back on we are going to do a leak test on the motor to make sure it's not hte motor.

Appreciate the help And if you got more ideas let me know.

 

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Ever see a motor pulled apart and notice the "scoring" in the front and direct rear of the cylinders? What's on the video causes that.

She is wrong.She has obviously never pulled a motor apart.MSF instructors are usually good riders,but most are "know it alls" and their MSF status somehow validates who they are and what they think they know. She couldn't be more wrong.Don't rev your bike like that 'til it reaches 180 degrees farenheit.

 

Damn, that whining first gear just made me wanna leave work and hop on my '97 F3. I wish that I could give some valid input, but I have never seen anything like this with my bike. All that I can think is to monitor your voltage like the others are saying and see if your regulator is acting up. How old is the battery in there?

 

I'd bet good money your gage cluster has disconnected. Have you been working on the front of the bike recently? When that is disconnected it will idle just fine but won't allow you to put it in gear and ride. It stumbles like the carbs are messed up. I'd check that plug before I did anything else.

 

After watching the video (didn't watch it befor eposting) I am 99.9% sure that your cluster is not connected or has a bad connection. No freakin clue why the F3's do that but they do. Its not the part of the cluster that controls the tach and speedo. Its the upper left side connector (when sitting on the bike looking at the guages). It controls a lot of things like the turn signals and the ECU.

 

This sounds like a problem I had. Am I correct to say you can rev it all day long but as soon as you get some speed it dies like its starving for gas? I've posted my results before. here is a copy of what I found out that fixed the problem.

I had a simular problem. It wasn't the air solenoid but close. Since this is carb'ed the bowls need to be equalized be cause of the direct air (I call it RAM Air). This is done with the D.A.I. or Direct Air Intake system. You have two lines that feed the air solenoid. Make sure the one (split into two)sticking out under your head light are connected to the air solenoid. This ram air is what creates equal pressure in your carbs so the bowls can refill with gas. That is why you are only able to get to so many rpms and a certain speed. Once the bowls are depleted it's basically a trickle of gas untill there is no more and the bike starves out. Send me an email if you have further question. Also, I posted all of my trouble shooting while I had this problem so look it up. It might help. Cheers Mate!

Jack Riddley
https://cbrforum.com/m_413195/tm.htm

Hope it helps!

 

I had a similar problem, it turned out to be a bad sidestand switch, the bike would start and ride but would cut out for no reason at anytime. I found it by playing with the sidestand comepletely by accident. water had gotten inside the switch housingvibration and heat would caused it to short. Try jumping the side stand terminals and see what you get