Motorcycle Repair: Honda CL450, air fuel mixture, combustion gases
QuestionHello, I've got a 1968 Honda CL450 with about 10K miles on it. The bike runs perfect and idles perfect, but when I get the bike up to right at 60 mph (give or take a few MPH's) It starts to cut out it's sorta like it hesitates, when I let off the throttle it goes back to running perfect. Then back up to 60 and does it again. It runs perfect and has plenty of power up to 60. It seems almost like it is starved of fuel, but I can rev the motor up to high rpms just sitting there and it won't cut out. I have cleaned the gas tank, replaced the petcock,fuel hoses and cleaned the carbs, new gas also. But still no luck. Also one other thing the motorcycle has a plastic hose that runs from the top end front of the motor down the back of the motor, between the carbs and down under the bike and everytime I ride the bike and get it warmed up it leaks out a foamy oil mixture out of that hose as soon as I shut it off. The more I ride it the more that comes out. What is this hose for? It looks like a factory thing. Thank you for your time, I do appreciate any advice you can give me on both problems.
Andy
AnswerAndy, I had a 69 CL450 and I loved that bike. I put over 25 thousand miles on that bike going to see my girl friend in Indy and tooling around in the summers. My brother still has it....great bike. Well, it sounds like you are running out of fuel. You can check it by applying just a little choke and if it runs better, it's starved... if it runs worse, you could be running rich. If it's rich, check the float levels to make sure they aren't set too high and air filters to make sure they aren't plugged. It's also possible if the exhaust has been changed it could be leaning out the air fuel mixture.
That hose is the breather hose. When the bike runs, combustion gases build up in the crank case and those gases flow out that hose carying small amounts of oil vapor and water vapor with them. That carry over is pretty normal.
Regards
Rich
