I have a 1993 CBR1000f. I've owned it for about 2 months. It starts up great each morning and I ride about 1/2 hour to work and runs great the whole time. She sits for about 9 hours and starts good when I leave. By the time I pull out of the parking lot the temp gauge is starting register heat.

Here is the problem. About 1/2 the time, when I leave work, I ride for about a block and I start to loose power. I pull in the clutch and the bike stalls. It takes some work (cranking for about 15 seconds) but I can eventually get it started again and then she runs fine the rest of the day. Any ideas? It doesn't really seem to matter how much I let it warm up before I take off.

Thanks!!!

 

You may have a partially blocked vent on the tank, or blockage in the tank filter........
Try running with your gascap cracked open and see if it helps.
May also be poor charging, if so check battery and Reg/rec.
May even be loose coil wires - or dirty plugs or......
So many possibilities.

 

I'm hopeful that it is a blocked tank vent. What's the best/easiest way to clean it out? I've not tried yet so it may be painfully obvious, but if anyone has any tips I'd be greatful.

Thanks!

 

There's usually a THIN tube that runs from under the tank to a spot just behind the filler cap, very close to the top of the tank. It's about the thickness of a paperclip, but be careful not to break the wire inside it or you will have to try option 2..........

I assume you've tried riding it with the gascap "cracked" to let air into the tank.
When the bike stops, open the gascap, if you get a "whoosh" you'll know the vent is blocked.
If you can't fix the blockage, let me know I have another option, but takes a bit of work, and removing your tank (again) It worries me that this is an "intermittent" fault, and it may not be the vent, but something else.
Are there any other symptoms, when it dies........?

 

GREAT info here. this is happening to my bike and i couldnt understand what was happening. my tank definitely has a woosh when i open it up after running the bike. i was under the assumption that the tank was under pressure in order to force the gas into the petcock on the lower half, but i didnt understand how an n/a vehicle could produce pressure anywhere since the motor is always in vacuum and there arent any vacuum lines that are post carb.

my bike would die after i would get it running like it was starved of fuel. it took a lot of time sitting there cranking and playing before it would light up again, but it seems to ride fine until it happened again. i was first thinking there was a pin hole in the petcock assembly area allowing air to seep by, but knowing that it could be a breather issue for the tank relieves me a little knowing that i can fix it in a short amount of time while i have the tank disassembled while painting it.

 

Try one more thing for me before we start - check the vacuum hose on the LHS carb and make sure it isn't leaking - that'll also cause a similar kind of problem. There's a hose from the back of the petcock to a fitting on the left side of the No1 carb. Pull it off the carb and suck on it - if you get air, the hose is leaking and that's your problem. If not then read on.........................


There's another way - I couldn't unblock mine after I had the inside of the tank coated, so did the following
1 Bought a hypodermic needle - from a vet with a diam of around 1mm - perhaps .0040 inch or so. I bent it into a U-shape (carefully or you'll kink it)
I then drilled a hole in the tank under the fuel cap, under the right side ( I can do pics if you need them)
NOTE - TANK EMPTY, DRY, AND SHOVE A VACUUM CLEANER INTO THE TANK TO REDUCE CHANCE OF ANY SPARK WHICH WILL MAKE TANK REALLY GO WHOOSH
Threaded the U shaped needle into the hole, so it was as close to the top of the tank inside as I could get it to reduce any chance of leakage.
Epoxied it in place.
Problem solved. Doesn't leak at all, and vents the tank perfectly.
Let me know if you need more help................