Diagnostic help!
 

Hello all - 1st off, I just signed up today so if I violate any unwritten rules about where to post or anything, my mistake. I'm trying to troubleshoot my 02 954rr. It runs fine in neutral, or in gear on a wheel stand, but whenever I try to ride it coughs/sputters/stalls out. Spark is good, it will re-fire every time it stalls. Looked at fuel system, all lines are good and pump still primes every time the run switch is flipped. I thought it was the kickstand sensor, so I bypassed that by removing it and splicing the wires together. Problem actually got worse. Should I check the kickstand sensor further up the line? Or does this sound like a more complex problem? Figured I'd check here before shelling out cash to my local shop, us I like to repair things myself if I can, just not a lot of experience fixing bikes. Any help is appreciated!

Fella, your last line said it all, if you have little or no experience of fixing bikes, then don't bother trying, you could end up doing more damage than good. Get it into a well recommended bike service centre and let them sort it. Sorry to be so negative but sometimes it can be a waste of time, money and effort to even try. Fixing say a broken front mudguard is one thing but something like this needs expert knowledge. Good luck.

Have you checked the basics like spark plugs, air filter, and fuel filter? Is the FPR leaking into the vacuum line?

Did you recently take anything apart and possibly leave a sensor, MAP sensor for example, unplugged?

Any info you can give will be very helpful....

you running an FI light? - i'm thinking a vacuum hose might be unplugged or pinched or something. it's most likely something really simple - start with small things.


how long does the fuel pump prime? if the fpr is bad, it will continually prime - and a drop in fuel pressure could cause the bike to stall.

so could pinched or un-hooked vacuum lines though

Further Info
 

@ Demon -
Thanks for the pointers. I have checked air filter, fuel tank, fuel pump (Only primes for same amount of time as for 2k miles before this started), hadn't tested the fpr yet because I wasn't really certain how. Also forgot to mention lights flicker when it lugs/stalls after bypassing kickstand sensor, which leads me in the electrical direction. Plugs don't seem to be an issue because it runs fine sometimes but I honestly haven't pulled them yet. In my experience bad plugs would be bad under all running conditions, not just in gear. As far as I could tell when I disassembled the tank/pump assembly, all hoses were connected with the exception of the weird t-joint on the air vent hose, but I saw a thread on this forum saying that's for the evap can on CA models, which mine isn't. Pinched hose was my 1st thought, which is why I removed the tank and pump etc. Fuel filter is good as well, free-flowing. Got a rec to check the Alt and Voltage Regulator because apparently those are known to fail in well-loved bikes(17k miles on it). Will post anything new I discover as I find it, but going out of town for the weekend (In a CAR https://cbrforum.com/forum/images/icons/icon8.gif) so most likely won't continue digging till Monday. Thanks to all responders, @ Hudson I appreciate the caution I'm actually using my mechanic as a sounding board rather than take the bike in because he's insanely packed and I'd be waiting for him to have a slot to repair it anyway. So I decided I'd try and figure it out in the meantime, if not, no harm done I can put everything back the way I found it.

Fixed!
 

Hi All -
Appreciate the input, I forgot to mention I also live across the street from a bike mechanic. He came over and gave me a couple things to check. Turns out when I had gotten down to the throttle body the first time, I failed to notice the hose from cylinder #3 to the MAP sensor was loose - not off, but loose enough apparently. We were tracing the hoses to make sure the vacuum system was intact and I spotted it. Pressed it back into place, and now she runs better than when I bought her. All the advice kept me from losing my cool, especially the reassurance that it was most likely something simple as I suspected. Thanks and happy riding!

Had a feeling about the MAP sensor. It can get over looked or knocked loose when the air box gets removed easily. Thats not the first time that its happened... glad you found it before buying tons of parts in the attempt to fix it.

it usually is something easy. glad you figured it out. i felt like it was going to be a vacuum hose or sensor.