Out of the blue bike runs like crap

[Remeber Me]

I was cruising down a road and stopped for a light. Bike was idling fine but when I took off it started stumbling and wouldn't rev up very high. I made it home but now it won't even rev up to 4k parked. I tried the fuel filter, no luck. Do you think it'w the fuel pump or something worse? The bike is in prestine condition with only 9k on it and never worked on.

 

[maleko89]

Check your plugs and see if any are fouled.

Take a multimeter and test for continuity of the secondary ignition coils to your plug wire boots. Reading should be between 19K and 23 KOhms.

Drain your float bowls and see if they all have close to the same amount of fuel in them. Look at the gas and make sure it's clear of debris and isn't yellow or brown (like Kloker's undies lol)

Mark
#1098

 

[Remeber Me]

Do I hook the meter up and test through the coil, or just both ends of the plug wire.

I haven't checked anything other than the fuel filter and pump yet. I took the top part (small side) of the pump off and didn't see anything so I put it back together. I then reconnected the pump's input and connected the output to a hose which I ran back to the tank. Then just switched the bike on and it seemed to pump gas quick enough. Is that a valid test or does even a bad pump always pass that test?

 

[maleko89]

Test with at the boot and make sure you contact the metal core. The (-) lead just touch any clean engine bolt.

I would think that the pump would either work or not run at all. If you fuel filter was clean I would look elsewhere first.

Mark
#1098

 

[gleno]

Have you checked the obvious?
Do you have fuel?
Switch to reserve and see if it stops stumbling.

 

[shawn kloker]

The basics,spark,fuel ,compression.

Bad gas?

 

[Rusty McNeil]

Just a thought.....

I've had this happen before, would have sworn it was igntion issue the way it was acting.

It turned out to be a sticking slide.

Stick a long skinny screwdriver down the throat of the carbs and gently push them in and quickly pull the screwdriver out to test that they are moving freely and returned easliy by the diaphragm spring.

Rusty

 

[Remeber Me]

Haven't checked anything else yet but I'll do the slide with I check the coil/plug wires.

Hal

 

[Robbarrie]

With only 9K on it - it shouldn't be anything major. I'd add seafoam to the tank and pour a little down in the carbs and let it sit over night. I'd also check around for a loose coil wire or plug wire. Is it stalling out ? Sputtering, backfiring, ect....? Are you blipping the throttle up to 4G. or are you just bringing the rpm up slowly to 4G. What happens when you choke it a bit ? I'm leaning towards an electrical problem side of things and not a fuel issue. Please give us more info.


Maleko - that was funy as hell, I think Shawn missed your comment. :biglaugh:

 

[Thevmaxrider]

Mine did something very similar and it was the CDI box that had crapped out. Of course my mileage was considerably higher than 9k at the time.

Cheers,
Jim Rodgers
VMOA# 4046
Western Ontario Chapter Leader:rocket bike:

 

[shawn kloker]

With only 9K on it - it shouldn't be anything major. I'd add seafoam to the tank and pour a little down in the carbs and let it sit over night. I'd also check around for a loose coil wire or plug wire. Is it stalling out ? Sputtering, backfiring, ect....? Are you blipping the throttle up to 4G. or are you just bringing the rpm up slowly to 4G. What happens when you choke it a bit ? I'm leaning towards an electrical problem side of things and not a fuel issue. Please give us more info.


Maleko - that was funy as hell, I think Shawn missed your comment. :biglaugh:

Yah,I was wishing that I hadn't already shipped those adaptors to him a couple weeks ago?









LOL!

 

[maleko89]

Shawn, haven't gotten the adapters yet.

Mark
#1098

 

[shawn kloker]

Shawn, haven't gotten the adapters yet.

Mark
#1098

What do you mean??????????

 

[maleko89]

What addy did you send them to? I haven't gotten anything.....seriously.

Mark
#1098

 

[jfeagins]

If I were a betting man, I'd put my money on a fuel PRESSURE problem. I had one of the internal valves on the end of the pump to disassemble itself one time and had a heck of a time getting enough fuel to run right. Seems like there is two tiny rubber one-way valves making up the inlet and outlet area of that fuel pump. One of the rubbers had popped out of its little hole and turned sideways. My clue was a constant pump clicking upon key on and it would almost never quit audibly pumping the entire time the bike idled. Good luck.

 

[Robbarrie]

Maybe if he reads this he will check it. However, he did not mention anything about the fuel pump constantly working ? Thanks for the heads up, I'll keep that in mind if the bike ever starts to do that.