Rear suspension project from Hades

T

trackfodder

Member
I built a springer front fork rather like a 1910 Pierce and the frame I had to use to accommodate the short stem was a Otasco lightweight 24". This made up my mind to build a spring rear end. I had a wild idea that I would pivot a swing arm from a 2nd shaft hanger with an English-style straight peddle shaft with 2 peddle arms keyed parallel with tubes welded over for swing arms. All the time thinking the front hanger was going to have bike peddles and sprocket. I didn't think it through too well and I had a situation where there was no room for a sprocket. Anyhow, I don't quit easily. I decided the front hanger would get good bearings and a shaft to serve as a jackshaft. I thought for a bit of using a Sturmey-Archer 3-speed rear wheel with a peddle sprocket on it, but this would rule out the HT. No way to push start with free wheeling. My current thinking is I have several rope start motors, and with a centrifugal clutch, I can put a spring-loaded split pulley from an AC treadmill on the front hanger and use an idler pulley and rocker heel-toe peddle like an old Indian or H-D clutch. With a tight friction clutch it would hold my setting. The other alternative is a long lever with a power hacksaw blade to hold adjustment like a 1910 or so motorbike. I think I might do a tank similar to a Silent Grey Fellow or Marvel either way I go. I think Servi Cycle used the rocker transmission. As for the rear end, extend the swing arms and put shoulder bolts on at the axle slot plates to pivot a front fork, facing down and 2 valve springs on the stem moving in a 1/4" plate mounted behind the seat post. The footpegs will be mounted in a gooseneck from a BMX bike with 4 Allen bolts. The gooseneck is seated in a vertical 5" tube hanging 4" in front of the shaft hanger. I triangulated horizontally back to the juncture of hanger and down tube. I can reverse the gooseneck to change bar position as soon as I overcome the D----ed GALL I raised by sticking a cold gooseneck inside a freshly welded tube and shrinking it tight. Live and learn.. If the front fork would benefit from it I can drop a 1/4" rod from the gooseneck and put a vented plunger ~half way down with a sliding sleeve to shut down the flow of oil on the up-stroke. A 1" X 1/4" double-lip seal will be held by the 1" top fork nut. As I re-read this I realize with proper springs I could put them inside the fork stem and put a pivoting plunger behind the seat post that would be captive with a snap ring under the fork nut flange. This would move in and out the fork stem. Gotta think a bit more KWscratg
 
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Re: Rear suspension project from Hades:Saga continues

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My wife ran out of things for me to do, so yesterday the newly leathered seat got mounted on the yellow thing and the pipe got bbq rattlecanned black. Today I again confronted the galling footbar gooseneck. I found my expansion reamers stop at 9/16" and being already 73 didn't have time for the VW brake cyl. hone. I attacked it with a moto tool as deep as it would go and finished up with a 1/2" rat tail file. It looked like it was a go until the
d---ed thing siezed up again. In desparation before plan B (BEAT it into place and weld it) I poured some Marvel Mystery Oil around it and BEHOLD. I got it out. A trip to the burnishing belt slicked it up.
I get distracted too easily. I got to looking at the frame,fork,wheels,seat assy of a stripped E scooter and specifically the rear brake. It is a cute external band that tightens on a cylinder on the hub. I then got to thinking, "What if the rear wheel off the other junker would fit the front fork. Then I would have 2 brakes." IT DID! Pulled the spacers and sprung the fork about 3/16" and it slipped in. I am not much on toy scooters, but this thing folds down and doesn't weigh much. That makes it car trunkable. The frame is only light rectangular tube box. The sprocket is 65 t. #25 and motor sprocket 11 t. =5.9:1. Assume my Kawasaki 32cc snow
blower motor will turn 5000 rpm, with 12" O.D. tires, it should run 30.24 mph.
Here's where you can help. Does anybody have any feel for how long those #25 chains will last? They put them on electrics and I see fat a--ed women that outweigh me riding them,so they must do ok, but don't want to commit any time if they don't. I don't have the coin for Gilmer belting. The Kaw has a centrifugal clutch from a Husky weedeater with a housing that I can put the chain in and go from a
1/4" square quill to an outboard support bearing within the tube. I think the engine is torquy but just didn't turn tight enough for my 1/4 scale Crackerbox boat. Maybe I will get some use out of it after
all. KW.cargo
 
A lot of things and re-thinking have transpired since the last update. Bottom line is I now have direction. I cut the frame off with the chop saw 3" above the C/L of the crank hangers and parallel to the ground. I fashioned a 16 ga. motor plate 11" X 4-1/4" and turned a 3/4" vertical edge on each side. The logic being with shape and an engine mounted, I have stability. The engine is now the 2hp Lauson out of the Skat Kat frame I am not doing anything with. The big surprise is when I remembered the kick starter for the B&S WMB fits the Lauson too. I now will have a slack belt going down to the shaft hanger jackshaft to a spring-loaded split pulley off a Sears AC treadmill. An idler pulley run by a rocker peddle like a Hardley clutch from years back with a stiff friction clutch on the pivot will squeeze the belt into action and change ratios by position. No centrifugal clutch necessary. I can also remove the starter hub on the flywheel side and skinny it up a mite. The fact that the belt goes down rather than back makes it possible at long last to use the kick starter The top and down tubes from the Sears Free Spirit I butchered will become my swing-arms. I only need to re-shape the cross section to accept the peddle arms by flattening a bit. The bottom section of the frame I chopped is welded to the bottom of the motor platform. The rear shaft hanger for the swingarm is just under the rear of it. I will roll 16 ga. around 1" round stock and cut thick gussets from it to re-enforce the motor plate to the front down tube and seat tube . The seat tube is now vertical just under the cross tube, with the seat post inside bent too. The front down tube went
from 45 to 53 deg. to meet the front of the motor plate. A big disappointment is the engine is about 2" from the top tube and makes it difficult to do a classic period tank. I think I will start out with 16 ga. rolled over the cross bar in a "U" and bent outward to form the tank bottom. We'll see where I go from there. I need room to access the plug. .bld. It will have to be fairly wide and tall for capacity.
 
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