hesitation/misfire

[mesmeralda]

I finally got the chance to take the bike to the track a couple of months ago and I had a new experience. While going through turn 11 at laguna i accelerated hard and at about 7,000 to 8,000 rpm the bike hesistated/misfired...once I shifted gears it was fine till i reached those rpm. Of course by that time I reached turn one and had to shave some speed off.
Am I hitting the rev limiter at those rpm's in those gears? I tried it on the back roads and again it hesitated again. It was kinda like a misfire but without the backfire. Anyone got a clue and fix.

 

[BA BUSA]

What year and how many miles

Sounds like a fuel problem...fuel filter or weak fuel pump.

 

[GIXERHP]

What is done to the bike, what are you running for fuel, if the bike is tuned for pump gas, it will not run properly on race fuel. I have seen this problem several times.

 

[mesmeralda]

stock 02 busa...prem. fuel....again only at high rpms

 

[NearDeath]

you should be running 87 on a stock bike, not premium... Many discussions between 87 vs premium... (Not that this should be your problem...)

Is it sluggish all the time and not as responsive as it used to be? Maybe run some 44K for Motos through it.

 

[BA BUSA]

(mesmeralda @ Apr. 24 2007,06:09) stock 02 busa...prem. fuel....again only at high rpms

How many miles

and the Busa is NOT tuned for premium fuel

 

[BA BUSA]

Bump for Chuckie

 

[mesmeralda]

32,000 miles and I've been running premium since I bought it in 2001. I tried to do it again and no hesistation but i read the tach up to 9,000....so my main question is what does it feel like when the rev limiter kicks in.

 

[bradsbusa]

bump for cheese

 

[Charlesbusa]

I had a similar problem.

When I was giving it full throttle and it reached those rpms, it stopped pulling.  To me it felt like the clutch was slipping.  If I gave it much less throttle, the engine would climb through those rpms, but not if I was giving it a lot of throttle.

My problem was not the clutch slipping, it was a bad fuel pump.  

To check for this you need to check your fuel pressure or get it dynoed.  Getting it dynoed was how I figured it out.  It was just above 100hp and went way way way lean past 5,000 rpm.

 

[mesmeralda]

(Charlesbusa @ Apr. 24 2007,20:24) I had a similar problem.

When I was giving it full throttle and it reached those rpms, it stopped pulling.  To me it felt like the clutch was slipping.  If I gave it much less throttle, the engine would climb through those rpms, but not if I was giving it a lot of throttle.

My problem was not the clutch slipping, it was a bad fuel pump.  

To check for this you need to check your fuel pressure or get it dynoed.  Getting it dynoed was how I figured it out.  It was just above 100hp and went way way way lean past 5,000 rpm.

Bad fuel pump....huh....any other symptoms?...It runs fine like I said...but during full throttle yes it does hesitate. Thanks for the idea..I will check it out

 

[Charlesbusa]

(mesmeralda @ Apr. 24 2007,21:42)

(Charlesbusa @ Apr. 24 2007,20:24) I had a similar problem.

When I was giving it full throttle and it reached those rpms, it stopped pulling.  To me it felt like the clutch was slipping.  If I gave it much less throttle, the engine would climb through those rpms, but not if I was giving it a lot of throttle.

My problem was not the clutch slipping, it was a bad fuel pump.  

To check for this you need to check your fuel pressure or get it dynoed.  Getting it dynoed was how I figured it out.  It was just above 100hp and went way way way lean past 5,000 rpm.

Bad fuel pump....huh....any other symptoms?...It runs fine like I said...but during full throttle yes it does hesitate.    Thanks for the idea..I will check it out

Nope, I didn't have any other symptoms.  Thats why I thought it was the clutch  

It was probably just a clogged filter, but since the filter is internal and a part of the pump, I just swapped out the whole pump assy(filter included) since it was an '02 with 35-40k miles on it.

View attachment blush.gif

 

[mesmeralda]

Thanks for the help.....I am taking it to the shop today to have them check the fuel pressure at those rpms. How hard is it to change the fuel pump? I see it's quite an expensive part too....any out lets or upgrades for the pump?

 

[NearDeath]

(mesmeralda @ May 03 2007,00:55) Thanks for the help.....I am taking it to the shop today to have them check the fuel pressure at those rpms.  How hard is it to change the fuel pump?  I see it's quite an expensive part too....any out lets or upgrades for the pump?

Easy to change pump... take tank off and unbolt it from bottom...


You should check your spark plugs and gap as well.

 

[mario_250r]

hi, same problem with my bike

How much is a fuel pump ?