Carb Overflow Issues

[RichBaker]

OK here is a little update to the bikes condition.

Once I changed the peacock lever position the carbs stopped overflowing. The weather has warmed up and the bike runs great. At random times during a ride it may have a bit of an unsteady idle, but thats about it as far as running goes. One issue I am having is electrical. For some reason most of the time when it happens, is when the bike has been running for a while then is turned of for a short period (like 10min) and tried to start again. The motor will turn but wont start. So I have to jiggle around the little 3-fuse fuse box located up front and keep trying it until I find the sweet spot for the fuse box and it starts. As soon as it starts its fine, the fuse box then seems to mean nothing. I have checked the connections and I see nothing wrong. Let alone I have NEVER had this problem when first starting the bike for the day. Something about heat seems to make this happen is part of my guess.

Next time, try cracking the throttle open just a very slight bit..... maybe a 1/16th turn or less. This always works with mine.

[Slick]

Ok so my carb rebuild kits came today. I'm actually outside working on them now.

Few Notes:

*Main Jet is 115 (Is that stock?)
*Carb #4 leaked gas(about half a shot glass) out of Cyl side of carb when removing carb rack.
*Tank is on ground with full tank of gas. Peacock works great, YAY!

Will report back when I'm done.

[Slick]

Everything went great. The bike fired right up after re installing the carbs and sounded better than ever. I let it warm up a little and stable out before setting idle. Then I took it for a ride around the area. The bike is so smooth and quiet unless you open the throttle. BUT........After riding for about 15min the bike started to bog and miss. It started getting worse, then worse, then stalled. It would not start back up. I waited about 15min and it started but was still bogging. Then as I rode for about 10min it got worse, then worse, then stalled. So same thing, waited 15min started the bike and made it home. I dont know what could be wrong. I love the way the bike runs before it starts acting funny. Argh, I was so happy......

[FJmonkey]

Maybe the float level, too low starves the engine, too high floods it?

[oldktmdude]

  Sounds like a fuel line routing issue to me. Check that the line is following the exact route recommended by Yamaha. Should be a routing diagram decal under the seat.    Regards, Pete.

[Pat Conlon]

+1 on what Pete said...  1) Check your fuel line routing. Very critical on early gravity flow bikes.
What is happening is when the bike is cold everything is fine until it warms up the fuel line gets soft and thus when warm/hot the fuel line becomes very susceptible to being pinched. It feels like your bike is running out of gas, and it is. Bike cools down, line hardens a bit, gas trickles into the carb's float bowls, bike starts and runs.... until the fuel line gets warm again, and again pinches off the gas......
Also,
2) Check that your 2 fuel bowl vent lines (the vent T's between #1 and#2 .. #3 and#4) are hooked up and are not pinched. The bowls need to breathe to get gas into them.......

Cheers!  Pat

[Travis398]

  Sounds like a fuel line routing issue to me. Check that the line is following the exact route recommended by Yamaha.
Regards, Pete.

+1 on what Pete said...  1) Check your fuel line routing. Very critical on early gravity flow bikes.

Cheers!  Pat

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