2005 FZ6 is bucking while in gear

[dirtbag]

If anyone has some insight into why this may be happening, I would be greatly appreciative:

While cruising at low(ish) speeds (40 MPH and under), my FZ6 bucks back and forth. It's extremely jerky. I have to give it throttle and back off instead of cruising at a steady speed if I'm going under 50, or the bike will start bucking like a bull.

I put a brand new chain and sprocket set on the bike, but that didn't fix the problem.

 

[Erci]

If anyone has some insight into why this may be happening, I would be greatly appreciative:

While cruising at low(ish) speeds (40 MPH and under), my FZ6 bucks back and forth. It's extremely jerky. I have to give it throttle and back off instead of cruising at a steady speed if I'm going under 50, or the bike will start bucking like a bull.

I put a brand new chain and sprocket set on the bike, but that didn't fix the problem.

Is chain slack set up within spec? What rpm are you at when this happens?

 

[FinalImpact]

What gear are you riding in at those speeds and are we talking about flat level ground or slight incline?

Do confirm that the brakes are not dragging also. . .

 

[dirtbag]

I don't believe the brakes are dragging, but I will check them today. It happens in all gears. As far as the slack on the chain, yes, it's right. I was thinking it may be my clutch, but it doesn't feel like it's slipping at all.

As far as the RPM goes, it can be anywhere. I don't generally cruise at high RPM's, but I would say anywhere under 7k is suspect. I can be on level ground, an incline, a decline . . . it doesn't matter. I'm just hoping that I don't have to install another transmission as I really don't feel like practically doing a complete engine rebuild.

 

[Erci]

I doubt it's mechanical. It sounds more like fuel delivery. I know there was a recall on earlier models, but not sure if it applied to 05s.

 

[ChevyFazer]

my bike was doing the exact same thing and when i hammered in it went away looked for about a week until i checked my battery, the negative had come lose check that first. look here http://www.600riders.com/forum/gara...engine-lt-bike-dying-bucking-like-bronco.html

 

[iSteve]

I agree with Eric sounds like fuel.

But I wouldn't rule out bad plug wire or loose coil wire connection or a bad ground somewhere.

 

[dirtbag]

Well, I know for sure there is a fuel delivery problem. When I bought the bike, the guy I purchased it from told me it had an aftermarket fuel pump on it. When I pulled the tank, the pump was from an r6 (although I've read it was the same fuel pump.) Anyhow, there is a vacuum line on the fuel pump that isn't connected. I think that's also the reason that the bike has it's other seperate issue, which is if you dump the clutch at any reasonable rpm (2500 or above), the bike will stall out. I've learned to deal with it until I had everything else straightened out so I could just take the bike apart one more time (hopefully) this season.

Do you think the problems are likely to be related?

 

[FinalImpact]

Why don't you give us the full history in one thread so we can connect all the dots.......

What other problems and some details on what hose is disconnected??

Where I was going with the "What gear question?" was that some riders could select a gears higher than the engine can handle for the speed. Example: trying to accelerate in 5th or 6th gear from 30mph could make it buck.

Some common issues that could be causing this:
-water in the fuel/bad fuel
-bad plugs
-electrically leaking coils, coil wires, spark plug caps
-defective TPS
-bad battery connections +12V supply or Ground (as mentioned on battery posts etc)

So are you saying it will do this in 1st gear at any RPM over 3000?

 

[dirtbag]

Why don't you give us the full history in one thread so we can connect all the dots.......

What other problems and some details on what hose is disconnected??

Where I was going with the "What gear question?" was that some riders could select a gears higher than the engine can handle for the speed. Example: trying to accelerate in 5th or 6th gear from 30mph could make it buck.

Some common issues that could be causing this:
-water in the fuel/bad fuel
-bad plugs
-electrically leaking coils, coil wires, spark plug caps
-defective TPS
-bad battery connections +12V supply or Ground (as mentioned on battery posts etc)

So are you saying it will do this in 1st gear at any RPM over 3000?

Sorry, I should have been more clear. The issue that I thought was unrelated is this:

If I am coming to a stop, I have to decelerate without hitting the clutch until the engine comes to about 2000 RPM. If I hit the clutch above 2000 RPM, the bike stalls. There is definitely a fuel delivery problem.

The last time I took the bike apart, I noticed that there was a hose missing from the fuel pump. Since it's not leaking fuel at all, I figured it was a vacuum line. I work nights, so I have to go to sleep, but I will take a picture of the fuel pump tomorrow and post it so you can see what I'm talking about.

 

[TownsendsFJR1300]

All 04's and some 05's had the TPS re-called. For the 05, it was recalled on the FZS6:

Recalls Summary | Safercar.gov | NHTSA



http://www.600riders.com/forum/fz6-...ou-experiencing-poor-idle-mileage-stalls.html

 

[dirtbag]

TPS has already been done and apparently the stock fuel pump doesn't have a vacuum line, so I'm going to do some "surgery" in the next few days. Maybe the fuel pump that's on there will work after splicing into a known vacuum line. I'll let everyone know!

 

[ChevyFazer]

umm a vaccume line on a electric fuel pump....i just got to thinking about that and no that cant be right there is no need for a vacume line on any electric pump, if it was mechanical yes but it dosnt have one for a reason, it could be the filter stoped up if he replaced it depending on how good of a job he did he could have got a good bit of trash in the tank

 

[TownsendsFJR1300]

There is no vacuum line on the factory original fuel pump. There's vent lines to the gas tank itself thou. That fitting on the aftermarket pump may be a vent. Make sure the vent line isn't kinked shut, that will cause problems...

There are two electrical hook ups, one for the fuel gauge, one for the pump itself and the fuel line connector. There is a filter inside (basically a steel sock) over the fuel pump...

The pump and fuel sender should be separated inside the gas tank to remove each assembly from the tank. There's a retainer clip that's a PIA to separate the two....

I would check the TPS just to rule that out. Its easy to check and will only take a couple of minutes. Make sure besides all the high and low #'s they are all there and don't skip any.. A faulty TPS will send mixed signals to the ECU causing other problems including obviously fuel delivery...

 

[ChevyFazer]

were you able to find the problem yet?