I bought an '88 XR 80 for my wife and daughters to learn to ride on. The previous owner said that it idled rough due to a home- made float in the carb. When I got the bike, I cleaned the air filter, { it looked like a dirt clod! } and tore the carb down and removed the jets and cleaned them out w/ carb cleaner and a torch tip cleaner. It ran somewhat better, but would not idle well. Smelled rich and had a stutter or stumble at idle. Air screw adjustment made no change. Ran the Idle screw wide open to keep it running. Most XR's i've seen have been bad cold-natured....not this one. It refuses to start with the choke on. The girls rode it a few times and complained that they could not keep it running when the rev's fell to idle.
The "home made float" looked good but decided to replace it with a factory one. Set the float by "eyeball" Its not spilling out the overflow tube so it must be close. Started badly.. had to push the bike and pop it into second gear and push to get it to light. Still has a rough idle and still smells rich. Shut it off and it started up fine with the throttle cracked. Left it for a couple of hours and tried to start it. Nope! No amount of kicking or pushing would make it light up.
I'm more familiar with 2-strokes and their quirks so I'm out of my area here, Can someone help?
Thanks
Dave salvaged@bellsouth.net
Hi Dave,
What's the plug look like? Have you tried a new one since you cleaned the carb? You might want to check the main jet. Kinda sounds like too big a main jet and cleaning it with a torch tip cleaner could have enlarged it & made it worse.Might want to check the exhaust also for any restriction. Just a few ideas off the top of my head. Good luck,
Perry
The plug was black and wet with gas. The exhaust is fine.
Yeah, I know about the tip cleaner enlarging the holes, I'm always real careful and poke just eneough to get any junk out of the holes. I've done it this way for years and have fouled up a couple of times.
I took the plug out and sprayed carb cleaner on it, I'll try sand-blasting it tomorrow. Then , I'll go buy a new one.
Thanks for the help!
i thought the 88 had electronic ignition??? have you checked the compression? when it idles can you put your hand by the exhaust and feel it sucking and blowing or just blowing. I'm wondering about a burnt valve. check compression then drop a spoonful of oil down the hole then check again. see if it goes up or stays the same.