(sorry i posted this in the 900RR thread before I saw the tech thread)

So I've been having tons of issues with my 98 900RR not wanting to start up after it sits over night.

I figured the carbs were dirty so I pulled them and cleaned them up really good, checked all the fuel lines etc. There isn't a fuel filter on this bike so I added an inline just to be safe. I'll start my bike in the morning it will fire up, then bog out and just die after a few min. Normally right after it warmed up. It will start up a few more times after that, then it won't start at all.

After I cleaned everything out (excluding the tank, just put new gas in it) it would still do this. So I read about opening the gas cap when starting it and sure enough it worked like a charm. The bike fired right up, I took it for a spin, ran it for about 40 min and no issues at all. Went home, waited till morning, tired to start, bike started the bogged out. Open gas cap again and boom, started right up.

I checked the hoses to make sure the breather hose was clean and not being kinked, it looks fine. I took my petcock valve apart and cleaned it, its seems to be working fine, drove the tank down to reserve and switched the valve over, worked good.

So I'm assuming the tank isn't releasing pressure somehow and this is causing it to not want to start, or maybe feed gas to the carbs. I don't think its vapor lock, but something similar.

I just did my carb adjustments, plugs, air filter, all that jazz about 4 months ago and when the bike finally runs, it runs good and strong. Only has 38k miles on it so I know I can get another 30k out of it if I can just fix this odd issues i'm having.

Any suggestions on this would be greatly appreciated, I'm stumped and the only fix I found was someone saying to drill a small hole in the gas cap. Which I won't do for obvious safety reasons.

Thanks everyone,

Amatsu

 

I think your on the right path with the vent line. Did you try to blow through it to see if its plugged? Just looking at it doesn't tell you if its plugged or not. Anything could happen. Dirt, grime, insects... all could plug the hose so air is not getting into the tank. Also, check the end of the line to make sure its not plugged or obstructed there.

 

Hello,

I did take the hose off and blow through it, the hose isn't plugged up. But should I try this with it on the tank?

My other thought was to drain the tank, get a pressure washer and see if i can blast out any dirt or anything may be blocking the vent to breath?
This is my first dealings with tank issue so I'm pretty much a noob when it comes to this.

Thanks!

 

Did you check it at the tank? Its possible the blockage is on the tank itself, not in the hose. Try to blow through the hose with it hooked up to the tank. If you can't, then it is more than likely blocked. You could try some small doses of compressed air through the vent line to see if it will break loose what ever is in there. the downside would be what ever is in there will end up in your gas.

Also, I would not suggest putting any water in your gas tank. that would be a huge mistake. Not only will it be nearly impossible to get it all out, but it can rust the inside of your tank extremely fast.
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On the tank, is the connector where the hose attaches bent or creased?

 

Shadow had problems similar to yours after having his tank sealed, he may be able to suggest something, but it does sound like you're getting a vacuum in the tank.

 

Thanks for the replies. I haven't tired to move air into it while its connected. The stem is good, no bends or kinks.

My tank was never treated or coated with anything so I'm going with there is crap built up in that area and its not allowing it to breath.. I'm going to drain it tonight and see what I can find.