Old Schwinn Road Bike Chop Chop Build

I thought some of you may be interested in what's going on with my Latest build - I am doing some radical engineering to rig up a swing arm dual suspension bike.

First, I started with a gigantic road bike that was given to me, set up for very tall riders. I chopped the head tube and the seat tube, removing almost 4 inches of tubing.

I'm going to affix a 1/2" axle perpendicular to the seattube with heavy welded steel. The swingarm axle hold a welded double sprocket offset about an inch that will feed the left side 36 tooth sprocket, anchored via clamshell on a 24" wheel. The swingarm width will be 7 inches, with my custom hub being 6 1/2" wide. The hub will ride on a 1/2" axle! It will take something to break that.

I am shooting for a 47" wheelbase.

I did some test fittings on the frame to get an idea of how it would look.

I'll need to dish out some money for sprockets, tube and tire, stepup drillbit (to put 5/8" bushing into swingarm), and two shocks to support the swingarm.

I will be running a 1' piece of heavy Duty unistrut along but slightly below the top tube/ down tube interface. That will hold a spring saddle and grab the top of the shocks.

 

[Timbone]

Here's a ride in the neighborhood:

 

[Frankenstein]

Of course, there are no instructions with the CDI. I ASSUME the key is set in the "Run" position. So I make one starting run. Nothing. Take a second run. Nothing. I check and recheck the fit of the spark plug cap. Take another run. Nothing. Check all the electrical connections. Take another run. Nothing. Use key to change the on/off setting on the CDI. Take another run. Vrooooom!

They state on the site the gold dot is the on position, or at least they had when I bought mine.

 

[Timbone]

With the warmer weather I’ve been enjoying longer rides, mostly at night after work. I noticed a vibration at cruise and saw a lot of chain side to side motion at my gear cluster on my swingarm. Bearing problems!

I was running the sprocket pair on several very thin 1/2” ID x 3/4” OD bearings. At least 7 of them, maybe 8.

I unfastened my swingarm assembly (I can do it from either side) and removed the gear cluster. Every bearing destroyed. Some moderate scoring was found in the swingarm axle.

I removed all the bearing pieces and sanded the axle smooth. I replaced the bearings with two 1/2” ID bronze bushings and greased the hell out of the axle before replacement. There was no play and I was able to turn the gear cluster easily by hand. My test runs were very positive: good cruise at about 28-30mph.

I checked to see if the axle or gear cluster was hot after the ride. Everything feels and looks good!

 

[gary55]

View attachment 80928 With the warmer weather I’ve been enjoying longer rides, mostly at night after work. I noticed a vibration at cruise and saw a lot of chain side to side motion at my gear cluster on my swingarm. Bearing problems!

I was running the sprocket pair on several very thin 1/2” ID x 3/4” OD bearings. At least 7 of them, maybe 8.

I unfastened my swingarm assembly (I can do it from either side) and removed the gear cluster. Every bearing destroyed. Some moderate scoring was found in the swingarm axle.

I removed all the bearing pieces and sanded the axle smooth. I replaced the bearings with two 1/2” ID bronze bushings and greased the hell out of the axle before replacement. There was no play and I was able to turn the gear cluster easily by hand. My test runs were very positive: good cruise at about 28-30mph.

I checked to see if the axle or gear cluster was hot after the ride. Everything feels and looks good!

On to the world of preventive maintenance.

 

[Timbone]

Yes to the preventive maintenance and to the creative process.

I’ve been given 2 140cc B & S lawnmower engines, one hardly used. I plan to convert them for horizontal use and get to work on a 4 stroke bottom loop frame, fabbed from scratch.

I’m thinking one gear left side drive running off a centrifugal clutch. Cafe Racer!

 

[Timbone]

Merry Christmas. Very interesting. I don't believe in it myself but many do. Spoke tying/soldering, I mean. Lol

Earlier in the week I was doing some short rides and I noticed one of the spokes on the motor drive side of the rear wheel had worked it way loose. Not broken, but it had worked itself free and I tried my best to thread the loose nipple back on but just couldn’t.

I few nights later I noticed that the spoke soldered to the loose spoke had broken. That forced me to undo everything, release the rear wheel and replace the two spokes. It was time for an inspection anyway.

Everything looked pretty good! The other 34 spokes are solid. I gave one a little bit of torque to tighten it up good. But the other 34 looked very nice. My bearings were good. The only anomaly I found was that the rear axle had a bend in it from being pushed backwards by the chain. Most important, the spoke flanges I welded onto my hub body looked great. No sign of any kind of failure!

I found a couple of spokes and nipples of adequate length and I replaced the two spokes. This time I was sure to coat the nipple threads with blue locktight. Brought the two spokes up to tension and in short order I had a surprisingly true wheel.

Of course, I wrapped copper around the new spoke intersection and soldered it up. I tell you, I think this makes for a much stronger wheel and prevents spike breakage. I figure at least 300 miles and just one spoke failure. Let’s see what happens when it warms up and we get out more...

 

[FurryOnTheInside]

Earlier in the week I was doing some short rides and I noticed one of the spokes on the motor drive side of the rear wheel had worked it way loose. Not broken, but it had worked itself free and I tried my best to thread the loose nipple back on but just couldn’t.

I few nights later I noticed that the spoke soldered to the loose spoke had broken. That forced me to undo everything, release the rear wheel and replace the two spokes. It was time for an inspection anyway.

Everything looked pretty good! The other 34 spokes are solid. I gave one a little bit of torque to tighten it up good. But the other 34 looked very nice. My bearings were good. The only anomaly I found was that the rear axle had a bend in it from being pushed backwards by the chain. Most important, the spoke flanges I welded onto my hub body looked great. No sign of any kind of failure!

I found a couple of spokes and nipples of adequate length and I replaced the two spokes. This time I was sure to coat the nipple threads with blue locktight. Brought the two spokes up to tension and in short order I had a surprisingly true wheel.

Of course, I wrapped copper around the new spoke intersection and soldered it up. I tell you, I think this makes for a much stronger wheel and prevents spike breakage. I figure at least 300 miles and just one spoke failure. Let’s see what happens when it warms up and we get out more...

Sounds to me like one spoke broke the other because they were wired and soldered together; but I can't prove that.

The forecast is for more snow again where I am. It's been a terrible cold spring, both land and sea temperatures are way below average. I can't wait get out and about, and do a real long distance ride to see if the plaice and turbot are showing. As I built my bike specifically for shore fishing and camping trips it hasn't been outside for months!

 

[Timbone]

Yes, it has been a long, cold Winter. Toughest month of March I can remember. Hope things ease for you and allow your outdoor activities.