Rough Cruising at normal speeds

[Jimingle10]

Hi, semi-new to forums hope you can help me!

For quite some time now, when cruising in just about any gear under 6000 rpm, the bike will not maintain the same speed smoothly. It will accellerate very smooth, but when i try to keep it at say, 40 mph....it will buck. A constant off/on feeling even tho im keeping steady throttle pressure. Even if i move the idle increase switch down to act as a cruise control...it still does it. Again this only happens at about 2% throttle, just enought to maintain speed. I noticed my front sprocket is hooked, and ordered a new Driven chain sprocket set that should be here soon. Could this be the culprit?

2nd Question - My fuel guage works from Full - Just before RED. The needle does not go any further, or into the red at all and hence no gas light comes on. Is the arm easy to clean or look at?

Thanks guys!

My bike -

2000 Busa (apprx 16,000 miles)
Yoshimura slip ons (dual)
Everything else basically stock.

Recent Tune Up
-Plugs
-Air Filter
-Brake Pads
-Synthetic Oil Change

Ive had the bike since 500 miles on the odometer....is there any periodic maintenance i should be looking into at 15,000+ miles? My uncle said something about a valve adjustment

 

[Jimingle10]

bump

 

[mike1180]

Welcome!



I would guess that you are not cruising in the right gear.
If the engine is forced to run at a low RPM it will buck.
I ride with my engine speed at 3000 rpm or more.
Nice and smooth and sounds louder so everyone around me knows I am there.
Try that and see if it helps.

 

[Jimingle10]

nah man its not the gear, like i said its noticeable under 6k. Whether it be 2nd, 3rd,4th etc it still bucks

 

[mike1180]

You said:
Again this only happens at about 2% throttle, just enought to maintain speed, and when you try and keep it at about 40 mph.
That is a different case than the below 6,000 rpm case.
So if you are driving along at say 5,000 rpm, (about 70mph?) it still bucks?

 

[Vigosama]

you are not alone, Mine just started doing that. I don't know if it is because I need the throttle bodies syncd, or if my gas filter( yes I know its the screen in the fuel pump) needs to be changed out. I have just got said filter in my grubby little hands so we shall see this week when I have a chance to dismantle it all.

 

[Jimingle10]

yes, it does but its less noticeable because your moving along and i tend not to hold 70mph steadily on the highway

 

[mike1180]

I would try and run some Sea Foam or BG44K or Techron, through the fuel system to try and clean it out.
That is a cheap way to possibly fix it.

 

[Jimingle10]

u use the whole quart or w/e size they are sold in like you would a car? or use 1/2 of it?

 

[mike1180]

I mix it as the instructions say, for the amount of gas.
It takes me about 3 tanks to use 1 can of BG44K.

 

[rpatenau]

Same problem here which has driven me crazy for a loooong time...

Seems like the engine is never really running right...

Talked to a mechanic who told me that a faulty TPS could cause this. Not completely dead so it doesn't give out a code but faulty just enough to get ECU confused if that makes any sense.

I guess it'll cost me about a hundred bucks to find out...I'll keep you guys posted...

Richard.

 

[Vigosama]

now i seem to recall someone posting something about resetting the throttle positioning sensor location, because it was giving a false reading. I dunno I am convinced that since I own a 2000 I should start with the fuel filter thing.

 

[Jimingle10]

Yea i want to change my fuel filter out too

Almost ran out of gas today, i need to fix my gas gauge problem too Is the arm/float for the gas level easy to get to from the bottom of the tank?

 

[Vigosama]

just changed my fuel filter. things to remember:
1> dont forget to buy new o-rings other wise you will spend a few extra minutes trying to fit the fuel filter cap with the old o-ring back into the fuel pump case...
2> don't curse when you spill the fuel
3> its way easier to remove the tank completely
4> after reassembling everything, don't forget to reconnect the fuel guage wire harness to the bottom of the fuel tank.
5> remember june is a hot month.... don't forget the air conditioned garage...
6>don't forget to clean the fuel screen.
7> thank your mechanic brother in law for use of his shop and all his nifty cool tools.
after all that it does run a bit smoother, I still have to sync the throttle bodies, and check the tps position.
Does anyone know how to get into dealer mode and set the tps?