No big deal.

Not anymore.... :D

Oh, and at least start the bike up and let it run for a minute before pulling the plugs (i.e. don't go out 3 days from now and pull the plugs without running it first - otherwise it won't tell you much).

weather hasn't been too nice tonight but was able to siphon the tank and leave enough in to let her run for a few minutes or so before taking the tank off to get to the plugs.

hey williepete,
i've been working on my own project the last couple days anyway jjust so you know if you want to post any pictures to us, just go over to photobucket upload whatever you like and when you reply (in here)and want to post a picture just go back into photobucket and copy the pictures url image (it will be on the right hand side of photobuckets screen)and paste it after your done with the text..
the reason i mention that is you have the tank off and if you want to snap a couple shots of the vacuum lines and carb setup we mught be able to spot something out of the ordinary.
now back to gas smell, if you keep the tank off and setup a temporary I.V. bag with gas in it and then run the bike, i would run my hand under the fuel lines that split and enter right before the carbs, you'll know if its leaking there pretty quick and this area is really common because the orings in that area start dry out after about fiveteen years.. ive had had to replace them on almost all my older blades.. and also alot of it will evaporate because it will fall on the motor first and unless you have a full on flood of gas going it will dry before it hits the ground.
im not sure what else i can add.. if you do end up pulling your carbs and cleaning them, i would right down the number thats on sides of the "main" jets.

Cool thanks for the tip with Photobucket! Here's my first attempt at it too.

Ran it for about 3-5 minutes before I took the tank off and plugs out. Just know that they look darker in the pics then when I took them out. Took the pics right away per plug. But they do look to be a little rich and were slightly damp around the threads when pulled.

WilliePete's Library | Photobucket

Ok well i took off the carbs to check the jet needles and found out that they dyno jet stage 1's. I will be adjusting them one notch up to lean it out a little and see what happens then.

Also added some more pics to answer your request earlier of what my vacuum line and such look like under the tank.

The PO installed the inline gas filter but I did change that out and replace all the gas hose segments about a month ago. The air vent tube terminates into nothing like my 96-98 service manual (in PDF format) shows. Also you can see the petcock diaphragm vacuum line is blocked off as the diaphragm needs to be replaced and leaks fuel if not plugged. Over then that I do not see or feel any fuel leaks.

CBR Troubleshooting Photos by WilliePete | Photobucket

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That's a problem. Probably THE problem. That should be hooked up to a connection right underneath the #2 carb boot. That's what is going to regulate fuel to the carbs properly. Replace the diaphragm because if it's leaking that bad - it means there's no vacuum lock - it's basically running the bike on PRIME - ergo terrible fuel mileage and running rich.


What happens when you take the tank off the bike? Does fuel pour out of the petcock? How do you stop the flow?

Just got everything back together minus the tank. Seen your post so went and took a look for the vacuum line as you said. Mine is located under the #3 carb boot. Then took a look at the petcock and cover set again a bit closer. As you can see by the pictures below I would def say the diaphragm is bad.

Petcock With Cover Set Removed. Photo by WilliePete | Photobucket

Cover Set, Looks Like Something's Missing.... Photo by WilliePete | Photobucket

Also I have to siphon the tank before I pull it or gas goes everywhere. Prob just gonna get a whole new petcock set because even the valve is sketchy/sticky when switching from ON to OFF to RES (back and forth and such).

Oh, damn - I forgot that part/didn't re-read it. Then that's definitely it. Your bike is running on PRIME because of the diaphragm. Leads to the richness you see on the plugs and the bad mileage

I agree - a new petcock would be a good idea. You should be able to find on ebay for a reasonable price. If there wasn't the issue with the handle, I'd say you should just remove the rubber and carb dip it to clean all that out. But all things considered - just get a new one. It's less of a hassle to pull it out of a package that the USPS drops off at your door than it is to replace everything needed and clean it.

But yeah, when you pull that vacuum line off - the petcock shouldn't really leak at all. That's why they don't have an "OFF" turn on the petcock handle, because it needs vacuum to flow.