Hesitation through 4K RPM

Ladies/Gents:

Accelerating through 4,000, I'm getting a cough and sputter back down through 3,800, then off and away smoothly back through 4,000 and beyond. It will go smoothly through this range if I'm non "on-it", but under hard/harder acceleration I will get it.

Thoughts?
Thanks in advance, Jon.

First---how old is bike,how many miles? Maint. history? How is it driven/ridden? Gas?

 Um, it a little early in the AM for my brain to be fully functioning, but I'm going to suggest that it seems to be a fuel delivery problem. So you might want to start by adding Seafoam to the fuel; checking the air filter to see if it's contaminated by oil or dirt; balancing the fuel onjection air adjustment screws; then replacing the fuel ressure regulator. In that order. My 2¢

Tim

Thanks guys, FYI

05, 37K miles, got it used, I've TAKEN CARE OF IT - It's my baby. Changed filters/oil when I got it, new belt, oil every 2 - 3 K miles (I know a bit overdone - but I get bored - lets go change the oil) Put some SeaFoam (abt 4 - 6 oz on 3/4 tank) in it this evening - see how it does tomorrow. I got a set of plugs, but haven't changed them yet - maybe this weekend. Driven every day, damn near my primary transportation. Noticed gas mileage down to low 40's - used to be high 40's. That's about all I can say. I don't drive it hard, but when I need to 'git, I do. Just to let you know about TAKEN CARE OF IT, my 95 Ford van has 400K on it - runs like a champ. That's what an every 3K service will do.

I bet a little speed limit exceeding will make some difference and installing the new plugs will fix her right up.   Mine is an 05 as well, with nearly 20,000 kms.  My mpg at last fill up is 52.4mpg.  When
I questioned for solutions to idle problems, following through on one suggestion (possibly from John) to ride it hard for a time, improved performance.  Replacing the plugs and a new battery fixed everything.

Let us know what you find ... thanks

Mike

This question has come up several times and the answer has not always been the same. Most of the time it has been related to old fuel or a bad ground or a battery problem. If you have not added fuel (you stated 3/4 of a tank) I would drain the tank and start with a fresh fill up. What they are selling as gasoline these days does not have a good shelf life. Let us know. Howard

UPDATE: SeaFoam seems to have worked. I still have a little "lag" as it were coming up through the RPM's (in the 5000's now) but not that bad. Also took it out to let it "breathe", 80+ mph for a good bit. Very smooth there too. So for now - I'll leave it alone. As far as my gas goes, I've started buying it on the main drag instead of in my neighborhood. Figure main drag gets more fuel more often, probably fresher. Thanks all for the advice and tips.

Jon

Check the spark plugs. Sounds like a misfire, will do it more after engine is hot and under a load.
MY 2 cents.

Plugs are cheap and easy to replace. Start there. Can't hurt! And if you want to stir things up around here go with NGK Iridium plugs... (I love them)

GHM-PM wrote:

<>... if you want to stir things up around here go with NGK Iridium plugs...  (I love them)

Iridium plugs, a Givi AF214 windscreen & Dr Pulley Sliders are the triad of improving the Silverwing. Once n' done.

Tim

janitorj1 wrote:

UPDATE:  SeaFoam seems to have worked.  I still have a little "lag" as it were coming up through the RPM's (in the 5000's now) but not that bad.  Also took it out to let it "breathe", 80+ mph for a good bit.  Very smooth there too.  So for now - I'll leave it alone.  As far as my gas goes, I've started buying it on the main drag instead of in my neighborhood.  Figure main drag gets more fuel more often, probably fresher.  Thanks all for the advice and tips.

Jon

You may want to try a bottle of Chevron Techron, not cheap but it is a good product, I'll run a bottle through all my stuff once a year.

oldwingguy wrote:

janitorj1 wrote:

UPDATE:  SeaFoam seems to have worked.  I still have a little "lag" as it were coming up through the RPM's (in the 5000's now) but not that bad.  Also took it out to let it "breathe", 80+ mph for a good bit.  Very smooth there too.  So for now - I'll leave it alone.  As far as my gas goes, I've started buying it on the main drag instead of in my neighborhood.  Figure main drag gets more fuel more often, probably fresher.  Thanks all for the advice and tips.

Jon

You may want to try a bottle of Chevron Techron, not cheap but it is a good product, I'll run a bottle through all my stuff once a year.

I buy a multi-pack of Chevron Techron at either Costco or Sam's Club. Much cheaper that way. And I too run some through my vehicles about once a year!!!