Columbia / Solo project begins - need info

Started work on the Columbia yesterday. The bike is in a very sad state, and I'm really crossing my fingers on the motor.

First a correction - From what I can tell, the (bronze) bushings on the pedal crank shaft are not 3/4 x 5/8, but are in fact metric 20mm x 16mm. I must have made an error with the caliper, as the micrometer is telling me 20 x 16. 16 mm is very close to 5/8", but I don't know how I managed to get 3/4" for the OD. If you look at a genuine German-built Solo moped, they use the same pedal crank as the Columbia - so it's not surprising that the parts are metric. Parts are on the way from McMaster ($2.65/ea), with some backups coming from Grey.

The pedal crank is bent, and I'm going to try truing it up today. This should go OK.

I got the clutch & magneto covers off of the engine, and found a fair amount of wet, chunky rust under both. The clutch side is bothering me the most, as it seemed like too much crud for the actual metal that was rusting. This engine has what seems like a variator on it, and I'm thinking that the rust is (was) the return spring for the moving pulley half.

The pulley half has free axial movement on the shaft, but it will set wherever I leave it. Shouldn't it have a spring that returns it to the open position?

The starting mechanism (under the same cover) is a metal leaf spring operated by a cable. The spring has a lot of rust damage right where it flexes, and I'm concerned that it has become weakened, and will fail at some point. I need to find a spare, soon.

Lower steering bearings are totally pounded out, lots of play in the front end. Hoping these turn out to be standard bicycle stuff, and that the lower cone can be replaced. Anyone had to do steering bearings on one of these bikes?

Lastly, I'm concerned for the motor. There was no air filter on the little BIng carb (anybody have a spare?) and there was a bunch of sand in the intake area. The throttle slide has scoring on it, and I'm fearing that sand made it into the engine itself. I'll have to pull the reed block out, and see what I can feel on the inside of the crankcase. About the reed valve, how do they hold up on this engine? Are replacements available?

Oh.. one more thing. The fuel petcock is shot, of course. Is there a petcock from another ped that will fit the Columbia? Is there another source for the part?

That's all for now. Thanks in advance for any advice or info.

Re: Columbia / Solo project begins - need info

A variator has a "return spring" but it's not a part of the front drive unit.. it's in the rear driven unit. Without the belt installed the front pulley side normally moves back and forth on the shaft without resistance.

When engine RPM decreases, centrifugal force on the weights in front unit decreases. The front pulley sides then have less force pushing them together. Tension on the belt is reduced.

The rear unit has a strong spring that forces it's sides together. This automatically takes up the belt's slack until an equilibrium is reached. In doing so the front unit pulley sides are forced apart to some degree.

can't help on most of the other questions.. i have made my own reed petals if that becomes an issue.. good luck with the project.

Re: Columbia / Solo project begins - need info

Legendre,

There should be a spring between the clutch plate (the actual plate, not the cover) and the other plate in there (the ones that connect to each other by these 3 thin metal "clamps" configured in a "triangle" formation-

If that's the spring you're talking about- then that's

KKM part# 732-0349 Compression Spring 2.28 O.D. x .90 I.D. x .83

For a petcock,

KKM part # 751-0248 Gas Valve M12 x 1

For a Bing Filter:

KKM part # SL-2074597 Intake Silencer

AND

KKM part #SL-2500328 Air Filter Insert

All of the mentioned parts here can be bought at Handy Bikes USA. They have great prices. But takes FOREVVVVVVVVVVVVVVVER to get ahold of them by email. It probably is better to call em. Ask for BJ (Bob Jones)

EK

Re: Columbia / Solo project begins - need info

joew,

Yes, I was wondering about this. On the Columbia, the driven pulley is not the spring type - it's just a simple pulley. The top motor mount is a bellcrank arangement, with tension springs on each side. The motor pivots fore & aft on the mount to compensate for the varying effective diameter of the front pulley.

I'm trying to decide where all this rust came from, and the spring-in-the-variator was just an attempt to explain it. Not enough visible metal damage in there to account for the quanity of rusty swarf that came out of it. I'm sure I'll eventually learn what it was.. heh.

EK,

Whoa! Thanks for those part numbers. Not sure about that KKM petcock; need to measure the threads on the spigot - the bike is a mixture of SAE and metric parts. I might just fake it, and get a hose fitting and an inline shutoff valve for a lawnmower. Most of the parts on it look like they came from the hardware store anyway, so I think that would suit it well.

In other notes, I got the pedal crankshaft straightened today. Did most of it on a 30ton press, and my friend finished it off in a lathe. Chucked it in, and used the toolpost as a reference, while he used a pipe to correct it. Got it within a few thou total error. The metal was a little tougher than it seemed at first.

I have a question about the driven pulley. There is a small metal bar which is secured to the back of the pulley, and it seems to be there to retain the drive sprocket. On my pulley, the part looks like it was worn-through by the sprocket, and I think this is related to the general failure of the pedal crank. Can somone confirm that this is supposed to retain the sprocket? There is a also a mechanism that selects moped vs. bicycle mode, but that is working fine.

Again, thanks for the comments.

Re: Columbia / Solo project begins - need info

i've heard people talking about how the engine itself on some bikes moves fore and aft to take up the belt slack.. so this is one of them.. at least it's clear that no spring is missing.

As far as where all the rust is coming from.. water is required for the reaction to continue so whatever is rusting is probably exterior.. and not in a situation where it would be coatd with oil. My bet is whatever rusted away will be revealed once everything is examined.

Re: Columbia / Solo project begins - need info

What about the backs of the side covers, they seem to rust nicely.

(I got your parts packed and ready to go)

Grey

Live to ride, Ride to work

Re: Columbia / Solo project begins - need info

Grey,

The side covers might account for the rust.. that, and the starter spring assembly that I mentioned. I'll just clean it all up and give it a go.

Thanks for the parts reminder, I'll get my half on its way to you tomorrow.

Re: Columbia / Solo project begins - need info

Legendre,

No problem. If you need more part numbers let me know- Handy Bikes are really good when they have the parts number.

As for that petcock, that specific petcock should be the right one- I bought one from them, that exact one and it fits perfectly. It's not the same switch as the original, but fits/works well.

Hmm... That bar- Are you talking about that bolt that is almost touching the belt on the front pulley? If that's the one you're talking about- it's meant to keep the belt on and to prevent it from coming off.

EK

Re: Columbia / Solo project begins - need info

EK,

The part I'm referring to is on the backside of the driven pulley - the black plastic one. You'd have to remove the pulley to see it. Just a little flat metal bar about 3/8" wide and 2" long.

If you look at the frontside of the pulley, you will see two bores with nuts at the bottom of them, near the pedal shaft. One of the nuts retains the moped/bicycle selector, the other retains the part I'm talking about. The selector is working fine - just about the only part in this area that is not broken.

What's weird, is that the part in question should not wear in normal use. About the only way to wear it out, would be to start the bike, switch it over to bicycle mode, then rev the motor (which spins the rear pulley) and eventually wear through the part. This doesn't make much sense, but then again - considering the state of the bike, I don't think the owner had the slightest clue about anything. Might be that they didn't have the selector set right, and the bike kept popping into bicycle mode while they were riding. That could have done it, eventually.

When stuff is so totally broken, like this thing was, it's always a mystery as to what went wrong first. Kind of a chicken-and-egg thing, where there are two conditions, either of which could have caused the other.

BTW, see your email about that custom-project motor.

Re: Columbia / Solo project begins - need info

About the Black plastic pully, If I get a pic can you show me what parts you need?

Grey

Live to ride, Ride to work

Re: Columbia / Solo project begins - need info

Grey,

I looked it over, and the part was clearly worn through. I was able to loosen the screw, spin it around, and tighten it back down. Now it's holding fine, and I don't see any reason for it to fail again.

If you looked at the backside of the pulley, you would immediately see what I am talking about. If the pulley were in your hands, try to pull out the central sprocket. A part stops you - this is the part I am referring to.

Anyway, parts should be here tomorrow, so I can reassemble it and then try the motor.

Re: Columbia / Solo project begins - need info

Ok. great progress today.

First off, apparently I've lost my touch with precision measurement tools. My initial comments about the pedal crank bushings were actually correct.. doh. They are a 3/4" OD x 5/8" ID x 5/8" long, with a 1" flange. Made from 841 oil-lite bronze, $0.63 each from McMaster; gotta love cheap industrial parts. The pedal crankshaft is 16mm, which is about 5 thou larger than 5/8".

About the whole bronze vs. plastic bushing thing. I noticed that the bushings on the pivoting motor mount are plastic, like the pedal crank bushings in Grey's bike.

The new bushings went in easily - just added a little chamfer with a file, then drove them in with a block of wood and a hammer. I then used an adjustable piloted reamer, to ream the ID to 16mm. Everything reassembled fine after this. I didn't actually measure the ID as I reamed it, just went by feel.

After this, I was finally able to turn over the motor - and it sounds absolutely excellent! Deep, throaty thut-thut-thut sound as it runs over without a plug. With the plug, it feels like there is plenty of compression. Tomorrow, I'll put a gauge on it and actually measure the compression pressure. But for now, it's looking very promising.

One more thing; a screwup worth mentioning. I thought I'd be clever and flip the pedal crank shaft around end-for-end when I reassembled it. This way, I would be running un-worn portions of the shaft on the bushings. Well, it didn't work. The keyways in the ends of the shaft are not cut exactly 180 degrees off from each other. When I installed the pedals, they were not in line with each other. I played with the pedal cotters, but couldn't find a way to make them line up. Eventually, I just swapped the shaft back to the original orientation, and the pedals were fine. I'm sure this is a common bicycle thing..?

Next comes the ignition, so I need a puller for the magneto rotor. Any idea on this one? Guess it's the same for a sachs or puch.

Re: Columbia / Solo project begins - need info

Good to here things are coming along. Keep us posted.

Grey

Live to ride, Ride to work

Re: Columbia / Solo project begins - need info

Legendre,

That's great! :o) Yeah, these engines are strong and nice running. Gotta love these. Did I ever mention to you that I know where you could get a NOS engine with a NOS carb and NOS exhaust all together for $125.00 shipped to your door?

I'll be mailing you your parts sometime on Friday. If not, then definitely by Monday. I'll include some small surprises. :o)

As for the magneto, I have no idea... I've never had to pull mine as I've never run into a defective one on a Solo engine.

EK

Re: Columbia / Solo project begins - need info

EK,

You mentioned that you had a hookup for NOS engines, yes. If the bike turns out to be a good one, I might just pop for the motor, and throw it on the shelf.

I'm not exactly sure what's up with the mag. The points are not opening at all, and I can't loosen the set screw. Screw is frozen up, and due to the acess (holes in the rotor) I can't get a screwdriver squarely on the head. I need to pull it apart and get it on the bench, to avoid making things worse.

Anyway, with all the rusty crap that came out, a proper cleanout is the right thing to do. Looks like the water got at the exciter coil, so it's good that you are sending a spare.

Re: Columbia / Solo project begins - need info

Legendre,

It sounds like it may be a good idea to maybe use the lower end Im sending you with your current midsection since everything in there is very clean and has no rust at all. (less work this way)

I also sent you an extra piston in good shape as well. Also, the head that I sent you- it looks good to me, so the water/antifreeze filler hex bolt might be removable on this one. Hope it is! :o)

The rods that holds the head in place on that engine is o.k., but I included mint condition ones as well. So you'll be able to remove these and put the mint ones in.

EK

Re: Columbia / Solo project begins - need info

Sounds like motor parts are taken care of. I found a set of bearings for the front end, I am sending with the rest of your stuff.

Grey

Live to ride, Ride to work

Re: Columbia / Solo project begins - need info

Heh, you guys totally rock! My moped parts stash is still in its infancy, but if you need anything, just ask.

I do have a few spares for 40T/50V Motobecane, and access to the largest collection of Parilla motorcycles & parts in the USA. Also a small horde of Suzuki T-500 parts here, and some Guzzi 850 T/T-3 stuff as well.

And should you ever need a vacuum tube or several, I'm the man.

Re: Columbia / Solo project begins - need info

Got any cafe' rear sections? lol

Grey

Live to ride, Ride to work

Re: Columbia / Solo project begins - need info

Ek, The fill hole screw on the head, Is it a normal type bolt? I have to drill mine out so I am trying to find out first.

Grey

Live to ride, Ride to work

Re: Columbia / Solo project begins - need info

Grey,

Mine is stuck really hard as well, I'm planning to try my luck with a propane torch & air impact tool. It's a plug, not a bolt - and my guess is that it's not a normal item at all. It does look a lot like the allen-head plugs used for the transmission and rear end filler holes on BMW motorcycles.

You might be best off to find a large nut, something just about the size of the top of the plug, and have it welded on through the hole in the center. If you're able to get it out, you can just keep using it that way.

Depending on how things turn out with my stuff, I may have a spare available in the future.

petcock

Hello,

The petcock from a Honda Hobbit fits perfectly! You will need to take off the crank and slide the main pulley a little to screw it on, but it works like a champ.

petcock

Steamboat Aka J. R. Stevens /

This is an old post. I haven't seen a post from Legendre in some time. Jim

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