McColough 32cc chainsaw bike

GoldenMotor.com

cannonball2

Well-Known Member
Oct 28, 2010
3,682
223
63
Colonial Coast USA.
Try those tall tomato juice, canned tomatoes or pineapple juice cans, those are usually big enough.
The parts needed are as follows-
1, fuel valve from Sick Bike parts.
1, 1/4" female copper adapter from any plumbing supply house.
1, double male hose to hose adapter and a hose bib cap.
1, short length of very thin copper tube to use as a gas cap vent.
2, extra hose washers.
1, roll of good silver based solder.
1,small can or jar of soldering flux paste
1, roll of perforated strap to use as mounting strap.
Please feel free to review my Copper gas tank under-
Iron Horse GT5R china girl build.
its in the
Motorized Mountain Bikes and Road Bikes section of this forum and the same construction techniques were used accept that you wont need to solder the end caps in place.
Hit me up if you need any help id be glad to walk you threw it.
FR
Thanks for the list, looks like I pretty well have most of it. Might make it for the fun of it then I would have to find something to do with it(not another build!)
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
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north carolina
Ever since I built my first friction drive people have said they tear up the tires, but I run smooth rollers and i have never had that issue. Maybe I'm just lucky
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
223
63
Colonial Coast USA.
Techincally the smooth roller has the most contact area. However it doesnt leave any place for water to go. I dont ride in the rain on any of my MBs, got a car for that. But I was returning from a long run in the country and hit an area that had just had a shower, was like walking on ice with the roller. Luckily it was pretty flat. Thats when a knurled roller is a good thing! Still I like the rubber roller, real easy on the tire, doesnt seem to care about dirt or grit and so far wearing like iron.
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
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north carolina
The ebike with the tire on tire drive is like that. I rode it through a puddle up to my feet on the pedals. when I came out, I kicked in the roller and it took off. It was slow a few feet but it dried off the tire quickly and was fine. In the rain it would have probably been worse.

Like you, I don't ride in the rain. I'm retired. There is nowhere I need to go, that can't wait. If there were my wife still drives, I can catch a ride with her on her way to babysit our grand kids. That and her volunteer work take a lot of her time.

I have actually thought about this, If I lived alone and was totally bike dependent. I would have one ebike and one gasoline bike just as I do now. I would have a trailer, just as I do now. I would go to the store, in the shopping center with an auto parts store as well, which is bout ten blocks away on either bike. The weather forecasters of rain are pretty good these days. II would lay in extra canned and frozen food enough for five days. I have never seen it rain any more than that. I live within a mile of three drug stores, not that I have any active prescriptions. I am within three miles. one way. of a wally-mart store. Three miles one way of the marina.

If my daughter wanted to see me, she could come visit me eight miles as the car runs. If not, life would go on, even though I would miss them and the grand kids. I think I could pretty much get bye with a bike and nothing else.
 
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deacon

minor bike philosopher
Jan 15, 2008
8,114
9
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As I expected I keep fine tuning the bike. It seems to do okay on most of the hills now. There are a few that require a pretty good pedaling to whip, but I can do it and still get home without being sweat soaked. Actually I sweat more adjusting the bike than riding it..

It's 8AM, I have to feed my dogs, then hit the bike trail in the park. I mostly ride it pedals with just a touch of power to get me home. It's good cardio and I love the morning air. Later.
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
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north carolina
I might have run into the faulty ignition problem cannonball warned me about. I rode the bike. And it did fine until the third mile at wot then it acted like it was running out of gas except it didn't zoom like they do at the end of the tank. It just sputtered then died. I raised the motor just in case it was out of gas, then went home. I filled up the tank even though it didn't need it and tried again. Still wouldn't start.

I'm going to let it cool off then try again.
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
Since my last comment: I removed the chainsaw motor, converted the bike to an ebike,and then destroyed the electric motor.

I decided today to go to plan 9 from outer space. I found an old front fork and a small wheel which was already stripped of some things. I removed the hub and used my angle gringer to trim the spoke ring flat on one side. I attached the hub to the bike's cross piece under and behind the saddle. Then I bought a couple of U bolts to secure it. After that I attached the chainsaw to the forks and hung it on there.

I forgot who had the idea, but he is a genius. The front fork and wheel hub after I thightened the bearing cones have far far less play than the henge. My guess is the vibrations are going to be way way reduced.

I also ordered what amounts to a generic 30+ cc carb on ebay. It is designed for a ryobi but i know from the position of the pump hole that it should work fine.

If the fork and hub cut down on the vibration as much as I think, then I am going to just wear out these little motors and then go buy another little motor somewhere. Weed whackers which were stored over the winter with gas are cheap. I can just move the carb from one build to the next.

Potentially I am looking at 25 bucks or so every few months to switch out the motors. The 31cc ryoby or bolan when not running due to a bad carb is about that or a few bucks more. The generic carb I bought has a squeeze bulb as part of the carb which should be much easier to use than the carbs that usually come with those things.
 

rustycase

Gutter Rider
May 26, 2011
2,746
5
0
Left coast
Great work, Deacon !
Are you able to post pics of your work?

...You might look into a small Mikuni carb that is acceptable for these engines.
I ran them for years on the larger dirtbikes, and they are a good product with good tuning options. Perhaps do some conversion work so a carb could be switched around from saw to saw using some short length of hose that is fuel/vapor proof? probably better to KISS...

With your use of the common U-bolts, you are probably getting closer to a universal mount which almost anyone can fab at home with minimal tools.
A GREAT thing!

LoL ..and even less $'s than a HT engine kit !

Best
rc
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
when ever I build it is with the guy down the block in mind. I really like the idea of a bolt on kid made from stuff that isn't specialty.

The best i can figure on the pumper carb is that they are pretty much interchangable as long as the crankcase vent hold lines up. So it is a matter of finding out which engines line up with the hole in the center of the manifold. In some I have seen recently the hole is off center but most seem to be centered up. I had a carb I pulled from an chainsaw a couple of years ago. it had a lot of excess stuff but when it came to the mount it was the same. The engine probably won't run as strong but the interchangeability is more important to me.

I have to buy some smaller u bolts by the way. The ones I got looked a little large even though they said they were the right size. I measured the hub at 1.25 inches so I bought a bolt I thought was 1.5 turns out I bought a ubolt for a 1.5" ID pipe. That makes the outside about 1.75 or about half an inche too big. Next time I'm going to measure the U bolt.

I have no idea if the saw will shake apart or not but It is held on only by the two studs used for the say blade. I used some flat steel to make a V from the fork with the bottom of the V being the studs. I have no idea what it will do.

I switch back to the 25cc blower carb just to see if the motor would start and it did. I had to drag it around for fifteen minutes before I could make it run. The pull start is pretty tough to do with things as they are at the moment I guess.

I would actually like to drag start the engines all the time so tell me, the pumper carp with the three stage choke. Would you still have to use all three stages if you were to switch to a total drag start. Someone should know the answer.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
223
63
Colonial Coast USA.
Man you jumped right on that fork band wagon didnt you! Actually I have been playing with one and and old coaster brale hub to use as a roller. The engine would mounted on the forks with the coaster hub where the wheel hub mounted. Belt drive of course. Still in the thought phase.
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
sounds to me like the ideal drive for a chain. You have the sprocket already there. If you used a 20" fork might fall right into place for you.

And yeah I'm thinking a donar bike from the thrift shop and strip enough parts to build one of these lift clutch friction drive bikes.

I know I can buy sprockets to match the bicycle chain from TNC scooters. That would be another easy project most likely.
 

FarRider

New Member
Jun 8, 2011
134
0
0
Brooklyn N.Y.
Thanks for the list, looks like I pretty well have most of it. Might make it for the fun of it then I would have to find something to do with it(not another build!)
Lol... bet ya cant build just one!
Thats why I love this hobby...I always have another build rattling around in my head or some one that wants one built for them.
The only limits are money, time, garage space and my lovely wife's patience for late nights with me banging around the garage...
(can i kiss up or what?)
So I say build on Mc Duff....
Make sure you fill the finished tank with good hot soapy water and a few big ball bearings and shake the heck out of it a few times to clean out any crap left in the tank... rinse, lather, repeat....
FR
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
I rode the bike on a day when my mind was pretty clear and I made the connections. If I shut the bike dies after a few hundred yards, it will not restart until it cools off. So I took it apart and found the white module that Cannonball warned me about. Now I'm not going to put it together, but I do have the small bike fever. So I put an advertisement on craigs list. Wanted to buy 30+ cc weedeaters. ryobi and craftsman mostly I'm sure.

I have one carb that is good, and a new one coming. So I should be able to take those 'left over the winter with gas' weekeaters and get them running. So if any of you have any old non working weed whacker you wish to donate for parts, let me know. I'll pay the shipping and give you a big sloppy online kiss for your help.

I guess i should start a new thread when I build the new bike. By the way the forks worked real good, but I needed more points of attachment with the motor to avoid vibrations.

Since the chainsaw has the same carburator mount, I might set it up as a cold test engine. Just to see if I can make a carb work without having to take an engine off the bike to test it.
 

LS614

Active Member
Dec 22, 2009
1,236
3
38
CT and MA
Deacon, this doesn't really help you at all, but I've been inspired by the work you and cannonball have made in this thread and a bunch of your threads and,well, today when I was working on another guy's bike, instead of asking for cash I asked him to pay me in weed eaters :D So I have a ryobi and a homelite 31cc and 25cc respectively :) I can't wait to play with this!
 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
and I just bought a ryobi 30 cc. I have it in the garrage ready to start. It has a bad diaphragm in the carb. I know this because it does the same thing the carb I built that never worked does. As soon as the primer gas is gone the engine dies. I am going to play with the carb tomorrow, then start working on the mount. Maybe we can do the buddy system, when I screw up Ill tell you so you can avoid the same thing.

I looked at mine, when I got it home. I think I maybe I can salvage the whole front of the engine. Usually I take the cases off these things. I might be able to salvage the pull starter though I have never been able too before.

Since I already have the fork on the back of the bike. Im thinking maybe I can mount an angle iron to the top connection point of the housing and then bolt that to the fork. Will still have to figure how to stabilize it on the bottom. Just have to think it through.

First though is to work on the carb. I am going to try to take that one, and the one I just rebuilt and try to get one working carb from it. If not I still have the generic carb on the way from ebay, and I have the blower carb that should work on it as well. So I can make my tests with it.

I am going to pick up another whacker tomorrow I think. I wonder if two weed whackers on the same bike would the same as a bigger motor. lol
 
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LS614

Active Member
Dec 22, 2009
1,236
3
38
CT and MA
Lol, I really love your posts Deacon, you are a true backyard engineer. I'm a little worried about finding the right kind of bmx peg and I don't know what I'm gonna do for a frame, but I'll figure it all out :)
Peace
-Luke

Hope this isn't thread jacking but here are pics of the extracted engines before overhaul and cleanup!





 
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LS614

Active Member
Dec 22, 2009
1,236
3
38
CT and MA
I'm gonna try to make this one pretty sturdy so the black likes are all angle iron, please ignore the fact that the engine image is turned the wrong way. I'm gonna use a door hinge and a wood mount. Wish me luck
:)

 

deacon

minor bike philosopher
Jan 15, 2008
8,114
9
0
north carolina
Most of them fit but here is a thought. take your engine to the bike shop. Tell the guy there what you are doing, then ask if he has any used pegs you can try the threads on. They usually do. Most likely he will do anything to get you out of his shop lol.
 

LS614

Active Member
Dec 22, 2009
1,236
3
38
CT and MA
The guy at the LBS is actually VERY MB tolerant, it's amazing, I know. I'm thinking because the threads are so far on the shaft I may have a spindle welded up that is like a bmx peg but has some sort of threaded bit in the middle so it will get close to the flywheel too

Can't wait to here more tips from you deacon :) Peace