[Axl_Rose]

I'm working on an 70's Honda 4-stroke motorcycle. It's been sitting for awhile so the gas in it went bad.

So I took the carb apart. Soaked it in parts cleaner and reassembled. My problem is that I can't get it to kick start(there is no electric). I can only get it to push start. Also it WILL NOT start with the choke on. It also doesn't idle well. It only idles at high RPM. With the throttle completely released it idles really high but it's not consistent. It fluctuates. I messed with the air screw and fuel screw and the only thing that seems to do is kill it.

I don't know alot about engines and such, but I'm not incompetent either. I have a haynes type manual that I was using. And the one thing I was wondering about was the jet that they call the "slow jet" Is the slow jet supposed to suck gas up from the bowl or does it get the fuel from the main jet? The slow jet has a hole in it that sticks down into the bowl. But I can't seem to get carb cleaner to go through it. I tried blowing through it also, and nothing goes through.

Can anyone give me some tips on what to do next?

[bigwill51534]

Many problems with older bikes comes from the carbs being messed with by numerous people who have no idea what they are doing. I'm not saying you are one of them, but many people think they are professionals with carbs who have no real idea what they are doing.

Anyway, there are just a few things that can be checked to get this bike running tip top. First off, pull the carb completely apart once more. There should be one small jet inside of the carb. It should have one hole through the center, and maybe 4-5 cross holes up and down the fitting. These holes get plugged, and parts cleaner will not clean them out. You must use jeweler's drill bits to VERY CAREFULLY clean them out without peeling off any metal (can destroy the jet). Be very careful, using the drill bits by hand to clean out each individual hole.

Next, just go buy a new set of points/condenser. I am sure the bike needs them, if it's been sitting any length of time at all. You can usually file the points, and reset them to the manual to make it run for a little while, but it's a good idea to change them as they are cheap.

Another good idea is to adjust the valves. They will generally stick and be out of adjustment from sitting a long period of time. I can't remember off the top of my head how to adjust the valves in that motor in particular, but you should be able to find a good resource on the internet.

Finally, pull the gas tank and clean it out. Look down inside it with a flashlight. I can imagine that you see rust and crud in the tank. You can buy Muriatic acid at most Home Depots or auto parts stores, which works great for cleaning out the tank. Plug every hold, remove the screen on the bottom of the tank, and rinse it out with about 1 cup of acid. Be VERY CAREFUL not to get any on your skin, as this shit hurts. Once you are done, just dump it out on the ground and dilute it with water. It's harmless once diluted. Then, rinse the tank with gas 4-5 times (maybe a few cups of gas each time, to ensure all acid is out of the tank). Replace all fuel lines as well as the fuel filters, unless they can be cleaned and reused.

This should be a good day's work, but will give you a good running bike in the end. I worked on 4-5 of them years ago, and they are a great motor. Just can't remember specifics. Let me know how things work out.

~Will Courtier~

[Axl_Rose]

Awesome. I'll try that.

When you say one small jet. There are 2 jets. The main ( the one the needle goes in) and another one(the "slow jet"). Was the slow jet the one you were talking about? If you were, the cross holes aren't plugged. Should the hole in the center go all the way through? Like If I blew threw the hole in the center should it come out the other side?

[bigwill51534]

Originally Posted by Axl_Rose

Awesome. I'll try that.

When you say one small jet. There are 2 jets. The main ( the one the needle goes in) and another one(the "slow jet"). Was the slow jet the one you were talking about? If you were, the cross holes aren't plugged. Should the hole in the center go all the way through? Like If I blew threw the hole in the center should it come out the other side?

I'm sorry, should have clarified. I was talking about the idling jet. Generally, the holes don't get completely plugged. They just have very small deposits of crud inside of 'em that are very difficult to see. The center hole should not go completely through, IIRC. It should just feed the fuel out the small spray holes in the side of the jet. The main jet might need to have the same job done to it as well, just through the single hole.

~Will Courtier~