McColough 32cc chainsaw bike

I picked up a working chain saw this morning and spent the day destroying it.

I had to:
replace the primer thingie
the fuel lines were rotted mostly.
It was covered with sawdust of course.
I flooded the carb with cleaner. It is now sitting over night. I will just try to run it again tomorrow to see if I have screwed it so that it never starts again.
I dont know if any of you remember the old comfortable shoes threads or not, but when we were building with the Ryobi weed whackers it had a 3/8 drive shaft like these chainsaw motors. We were using axle pegs as drive wheels. So I went by the bike shop where they sorta know me. I found an old bike peg about 1.5 inches in daimeter with a 3/8 inch hole in the rear.

I removed the clutch from the Mac and took everything off the drive shaft. I put a 1/2 nut on the back of the drive shaft as a spacer, then put on the axle peg. Another 1/2" nut inside the peg to take up some space, then a lock washer and the original nut from the clutch. It is threaded backwards by the way. So it is tight and when all the carb cleaner is out of it tomorrow, it should run. It is longer than I like, so most likely I'll use the angle grinder to cut it off some, when I know what the mount is going to look like. I don't have any idea yet.

When I went to pick up the primer bulb... I asked the old old man who has been working on small engines for years and years, "Hey I just bought this mac is it any good."

He looks me in the eye and says, "No."

I said, "Really?"

He says, "Poulan, Mac, and Homelite are crap these days."

. It's like I told him, they are the only ones that are cheap enough to build a motor bike with, so I'm kind stuck with one of those. I'm not paying the price of a two kits for a motor just to butcher. So we will see.

Today's project is to get the cleaner, cleaned out of the carb, and to give it a through engine test running with the spindle on. I took the clutch off it last night and installed my spindle. I have no idea how it's going to do.

It's a 3200 with a plastic case and a pure pain in the butt. That muffler placement drove me nuts all day. I finally over built the frame enough so that I feel fairly comfortable that it won't twist itself apart on the first day. I have it on the bike now and the hinge locked into the up position so that tomorrow I can work on the engine. I got it started today without too awfully much trouble. I had to pour gas down the throat the first time, but I could also see that it is pumping and I could run it as long as i kept the throttle open but that is almost impossible with it sitting on the ground and the throttle being a loose piece of cable.

Now that I have it on the bike I can rig a throttle and at least test the motor. Right now the lift is just a "L" bracket attached to the bike frame and a 3/8" bolt holding the motor frame in place. I can lift the motor and lower it but it isn't perfectly steady. Nonetheless it's the only way I can get the drive wheel down close to the motor and I know from experience the farther out they are the more likely they are to break the drive shaft.

The more I aggravate over this thing the more I think i might go with a friction kit next time, If i find one I hear good things about.

I got my ebike fixed. I had too much tension on the drive and it was bouncing around. I removed almost all the tension and the bike is much better. I'm going to remember that on this gas bike as well. You want the drive to skip over the wheel rather than bog down. Well that is if you are using a small engine.

If it is one of those diaphram carbs they are made so they will run upside down. How well I have no idea. I never have considered the position of one of those two line carbs maybe I should have.


I am using the off side henge to guide the motor to the right place Hopefully to keep it from walking. I do not plan to raise this one more than a half inch since it isn't on a hing. It is on a 3/8bolt well greased of course.

Now I have a question... I have often thought about trying this if one of you has it would be interesting you know your results I will be doing it tomorrow. I use a lot of those brass cable stops. Most of them are large enough to slip two small cables inside. So I'm going to try to splice two cable together with one tomorrow. Just curious to see if anyone else has tried it.

In my case I have a carb I slipped a brake cable through because it had that lead end. I didn't have to make a linkage. So If i can mate it to the shifter, I wont have to fool with redoing the carb cable.

I'll try to shoot some tomorrow. I have a date with an early morning ride through the walking/bike trail with my ebike. After that I am going to try to get a throttle rigged so I can finally work on the engine. I will try to shoot some picks.

That's what I thought on the chainsaw as well. I used to mount weed eaters all kinds of ways. I rejected a tyobi 31cc weed eater last week in favor or this saw. I'm more familiar with the ryobi than this thing but at least the mac has a simpler carb than the poulan saws I have used. Good to know about the electrical splices if the brass wont hold I will give that a try.