Hey everyone. I tried searching the forums but couldn't find anything in particular to my issue.

1993 CBR900RR.

I haven't been able to start my bike for 6 weeks, felt like it wasn't getting fuel. Trouble shot everything I could think of, pump, pump relay, fuses, and everything appears to be good. Finally I decided to open the gas cap and try starting the bike, bingo, bike started right up, didn't have to give throttle or pull on choke, which normally I would if the bike had been sitting for a week or so.

After this, I have been able to start, stop, and start the bike with the gas cap closed with no issues. Took a 4 mile round trip ride to test it out.

My thought is that there is a vacuum issue, perhaps the overflow and breather hoses are somehow clogged? I'm going to try 2 things, run a flimsy wire down the overflow hole in the gas tank opening, or use an air compressor and shoot some air in it.

I am not a mechanic and my automotive skills are limited to brakes and changing oil. I do have a repair manual and the internet though and am able to learn if given the right instructions.

Not sure if this is related to the starting issue or not: bike seems to be blowing the high beam in the headlight bulbs every time I put a new headlight in (no, I am not touching the bulbs with my fingers and getting oil on the bulb).

Anyone with any advice or knowledge of what I am experiencing with the starting issue?

 

Easy - the air vent on your tank is blocked.
Thin strong wire should clear it - if not there's another solution .........

The high beam issue isn't related to the fuel problem.
You need to check the connectors from your globe to the loom - if they are loose you could get intermittent problems which may blow your bulb.
Let me know if you need any more help.

 

If you used compressed air to blow the vent out, be sure to leave the cap open.
You can ballon your tank, if not. While you're dealing with all of this, pull and
clean the petcock/filter and rinse the tank with kerosene. That will get rid of any
of the sediment stirred up, that was previously settled in the bottom of the tank.

Ern

 

Awesome, thanks for confirming my suspicion. Will give it a go after work.

 

Well seems to be something else wrong. After running great, I started to ride last night and after a mile it began to run rough and even stall. Exhaust sounds deeper and throaty. It's beyond me, thinking carbs and or jets need to be looked at. More than likely will be taking it in.