Idles fine but dies when I give any throttle.

[Kat_Ryder]

Last week I pulled the K&N air filter out and put the stock filter back in. (I was not happy with the K&N using either donut)
I did not start the bike at the time because what could go wrong. Today cold engine, set choke and it starts fine as the engine warms up the rpm's increase and I give it some throttle and the engine dies. If I give any throttle at all the engine dies.
Using the choke I can take the rpm's up to abbot 4000 and it sounds fine, stop the choke and it idles fine, but give any throttle at all and it dies.

2001 Katana 750 with Yosh slip on.

Thanks in advance Mark

[Kreylyn]

Sounds like not enough fuel is flowing atm... check the petcock connections, vacuum to the petcock on the carbs is connected, etc...

Krey

[brentwoodkris]

Sounds like not enough fuel is flowing atm... check the petcock connections, vacuum to the petcock on the carbs is connected, etc...

Krey

I definitely agree with that. You could also TRY (and I'm going to get pounded on this) running the bike on Prime, which would allow the fuel to flow freely on it's own. That should tell you if it's a fuel delivery issue or not.

[MrSandman818]

Last week I pulled the K&N air filter out and put the stock filter back in. (I was not happy with the K&N using either donut)
I did not start the bike at the time because what could go wrong. Today cold engine, set choke and it starts fine as the engine warms up the rpm's increase and I give it some throttle and the engine dies. If I give any throttle at all the engine dies.
Using the choke I can take the rpm's up to abbot 4000 and it sounds fine, stop the choke and it idles fine, but give any throttle at all and it dies.

2001 Katana 750 with Yosh slip on.

Thanks in advance Mark

It could also be a problem with the airbox not completely seating on the carbs. Usually on the bottom of the 2 middle carbs. When that happened to me I went back and checked the air box and thats all that was. Just a guess

[Kat_Ryder]

Thanks for the suggestions.

Thanks for the suggestions. I will get into it today and let you know what I find.
Mark

[bob393]

My 94 750 does the same thing when its ice cold but gets better when it heats up.
I still haven't fixed it!

[rigidone]

yep krey hit the nail on the head, also check all 4 cyl for compression....

[Kat_Ryder]

running now!

After trying all the suggestions and replacing the spark plugs I had the same problems. I had my son come over to help me. ( He's a mechanic. )
He drained the float bowls looking for water, but did not see anything obvious just a little sediment. Then he unplugged the wires on the left side in the rubber boot where the signal generator wires are and after cleaning, plugged everything back together. The bike started and ran great after that, not sure what it really was.
Mark

[Kat_Ryder]

Engine died going down the road.

After fixing the first problem I had it out a couple of times and it ran great.

On Saturday I was going down the road at about 65 mph and felt it lose power then the engine died. It would start but died every time I gave it gas. I had to tow it home.

One thing that was common to both times it went bad was that I had a full tank of gas ( filled the day before ). I'm not sure it that has anything to do with the problems or not...

Today I managed to get it running again by starting it and using the choke to get the rpm's up to around 4 grand and eventually I was able to use the throttle again and now it is fine, starts and I can give it gas and ride it.

Needless to say I have lost all confidence in it until I can figure out what is causing the problem.

Mark

[Kreylyn]

After fixing the first problem I had it out a couple of times and it ran great.

On Saturday I was going down the road at about 65 mph and felt it lose power then the engine died. It would start but died every time I gave it gas. I had to tow it home.

One thing that was common to both times it went bad was that I had a full tank of gas ( filled the day before ). I'm not sure it that has anything to do with the problems or not...

Today I managed to get it running again by starting it and using the choke to get the rpm's up to around 4 grand and eventually I was able to use the throttle again and now it is fine, starts and I can give it gas and ride it.

Needless to say I have lost all confidence in it until I can figure out what is causing the problem.

Mark

I would consider a general cleaning on the carbs. You mentioned that he drained the bowls last time... this could have allowed any sediment/floaties in the bowl to drain away from the jets, and just took a while before they were pulled back into a jet(s).

Pull the carbs off, clean the bowls, blowout/spray out the jets. Be careful with carb cleaner, don't spray it on/in any place that you still have rubber orings or the diaprham in. Remove those before cleaning with carb cleaner. Re-assemble and go.

You will probably find some stuff that will make it fairly clear if it was dirty carbs. BTW... if you do find something in the carbs... drain and flush the gas tank as well. Inspect for any rust. Remove the rust and treat the inside of the tank before putting it back on the bike... or you will need to clean the carbs again.

Krey