Fouled plugs, no power

jrmsr

Registered
Out of the Blue, my plugs just started fouling I believe. Put in new plugs, started right up, sounded and felt good at idle, and reving. Went for 10 mile ride, got worse and worse, no power. full throttle barely could pass a car at 60mph. By the time I got home no power at all, maybe 50 mph max speed, used 1/5 tank of gas, going 10 miles.
I will pull the plugs again, expect them to be fouled.
Anyone know what can cause this
I had something similar one time before, when I forgot to at attach IAP, but have it hooked up this time. Also this time much worse
Appreciate any help, will go through it again when home in a few weeks
 
What year? Is there surging? Is there a limit to the RPMs? May be a fuel pump problem.
 
My 2cents..learning about bikes but know import cars and I have run into that with a couple swaps.on a car there is a crankangle sensor if its,dirty,bad, or out of adjustment(gap between sensor and indicator on pulley or cam sprocket)it will not read correctly and mess the timing up and foul plugs.sensor tells computer when #1cyl.is at TDC then fires at a certain angle of crank for optimal combustion.
Just learning as I said but someone could chime in and answer this, but a bad O2 sensor will do the same thing by telling the computer the exhaust mixture is to lean and it will dump fuel trying to correct air/fuel ratio.I know cars do, but a hayabusa ,if controlled by a computer,run in an openloop program when motor is first started then when all needed sensors are up to operating temps.the computer then relies on the sensors to tell it what it needs to adjust.maybe why it idles fine but down the road when the sensors are up to oper. temps. it gets south on ya.
Like I said I'm learning and I hope I havent confused or told you wrong I'm trying to contribute because the great fellows here have helped me.
Whiteboy06
 
Crank sensors are typically an all or nothing part (pass/fail) (worky/no worky)

Check your vacuum system (especially to the MAP sensor).. this sensor tells the fuel system how much load the motor is under and adj fuel mixture accordingly.. A broken vacuum line tells the sensor that you are at WOT

few other things can cause the same issue but this is the easiest and most likely.. at least a place to start..
 
Crank sensors are typically an all or nothing part (pass/fail) (worky/no worky)

Check your vacuum system (especially to the MAP sensor).. this sensor tells the fuel system how much load the motor is under and adj fuel mixture accordingly.. A broken vacuum line tells the sensor that you are at WOT

few other things can cause the same issue but this is the easiest and most likely.. at least a place to start..
Wow, thanks for all the quick reply's already.
For sure it is not timing, or anything fixed. I can put new plugs in and it will work almost fairly well for a couple of miles, then the plugs foul worse and worse by the mile, till almost no power.

2000 with 88,000 miles. I ride 750 miles a week to work (except Winter). It has been fantastic, always felt better than new. Except for the last time I fouled the plugs, IAP unhooked.

What does the MAP correspond to, I don't have any sensors with that designation???

I am studying all the sensors in the manuals and taking notes. Will not be home for two weeks, then I can start working on.

One thing is for sure, a BUSA's not worth **** without its power (G).
Really appreciate all the replys

Jim Morrow
Union MO
'00' R1100RT
'00' BUSA
'06' KLR650
 
The MAP sensor is Manifold Air Pressure

An engine under high load has little or no manifold vacuum in "most" cases, the sensor tells the computer to widen the injector pulse width to richen the the mixture.. so bad vacuum, rich condition..

Follow your vacuum lines, one will go to a unit with a vacuum line and some wires.. can not be hidden that well (I would look at mine but I am in process of trying to get my corbin seat to set down)
 
Sorry, brother, but I gotta be the "acronym nazi" here. please don't take offense, as none is intended.

MAP stands for Manifold Absolute Pressure

It's a sensor that monitors the differential in ambient and manifold intake pressures.

+1 on the advice.
 
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