Got some more parts but couldn't get a coaster hub. They didn't know what I was talking about, so I was going to show them one on a kids bike. Nope, all of them use freewheel with band brakes. I wanted to use a chain and have front brakes with a coaster hub. They had an old steel rear hub for a band brake that looked good enough for Patty's front hub.
They did have some parts for the crank but not for cotters, but the old spindle worked with the new cups. I have the 44 tooth cottered carnkset from 2014 that has weathered and looks right at home on this frame.
I did all the drilling and made up the front wheel, same as the rear 60mm wide.
None of the shops had any spokes longer than 258mm, and I needed 263 for my front wheel so I laced it 2 cross to make it work. The front will have a band brake. All the wheels need now is truing up. I'm going with the original plan, big whitewalls.
Next up is the frame extensions. They need cleaned up and holes drilled. I also have a lot more flatbar to make brackets for supports and brake mounts.
Before I work on the extensions or have the wheels trued, I wanted to get an idea of where and how the seat would attach and the height. I want to be able to sit flatfooted but not too low. It's only 86 inches long.
I need a plan for the seat, I'm thinking of two parellel bars like the cantilevers to bolt it to, no seatpost.
All my lacing was in vain. The two mechanics at the bike shop rethreaded everything into a pattern I've never seen, to true up the wheels. They both worked for an hour to finish them. But they are ready to go.
Now I can focus on the frame. I can work on rear brakes later as I have front brakes now. I'm going to make braces for the frame and attach the seat to them in some fashion. The idea is to make it all integrated and solid. I've got about 12 feet or so of flatbar to use, the same stuff I made the rim brackets out of. Finally I'll draw up the handlebar design for the stainless shop who will make them up. I'm going with a lower rise and much longer length so I don't have to stretch for the bars.
Unique wheels, persistence pays off! Build is moving along well
Wow, as builder I appreciate the picture of the fellas working. Those are 60+ year old truing stands from China or Taiwan. Please do get a closeup of the stand base and post it if you can. Should be stamped.
They were most impressed by being able to ride with one tire flat with the two tire setup. "Like a truck with a flat tire!"
I'll get a pic of the stands, I did see something stamped on the bases. These guys are adept at using them, usually only 3 or 4 minutes to true a wheel. They enjoyed a challenge with my wheels though. They kept asking questions on lacing, if I approved. I had no idea, just nodded.
I was going to sand the blue paint off the fork extensions when I remembered the extensions I had made up to extend the rear of a frame. I gave them a try and I like them a whole lot more than the round ones.
I want to be able to change out from single to double tires without making any adjustments to the forks or frame. So I checked the width, 3" for the 26 x 3 whitewalls, no surprise there. The two 2.125 tires together have a width of 3 1/2 inches, or 90mm. The height is 28" on the whitewalls and only 26" on the double setup, so I checked the pedal clearance. If I have the extension all the way down to where the cantilevers touch the downtube, the pedals are only an inch off the ground. I'll keep them up at about 3 inches. Clearance wasn't a problem on the rear.
The tires clear the fork arms by a hair, so they will need a 1/4" spacer on both sides. The bolt is long enough for that so it's good.
I worked on some brackets and was waiting for my drill to recharge when an idea hit me. On my previous build that never had a frame, 4-4-2, I was working with two chain wheels to add more gears with a SA 2 speed kickback hub.
I thought the cottered cranks had no way of doing that but looking at my sprockets I see how it can be done. I have a 40 tooth and a 44 tooth cottered crankset. The chain wheels are slightly concave so I can cut the smaller one out (they are one piece with the crank arm) where I drew the blue lines. Then drill 5 holes to match the larger one and bolt them together, flipping the smaller one to the outside. It looks like enough spacing for the chain, but washers could be easily added to make some space.
With the SRAM automatix, that makes 4 speeds, but how to shift between the two chain wheels? I had made plans for long dropouts to take up the chain slack and align the rear wheel every time I changed the front gearing, on 4-4-2. This hub is freewheel though, so there's no coaster brake to have to contend with. But I don't want to have a cable and shifter and derailler to deal with. I'll keep it simple and shift manually up front.
I saw a pic of a floating sprocket and that gave me yet another idea. Between the two chain wheels, 44 and 40 teeth, could a floating chain wheel take up the slack when dropping down to the smaller chain wheel? I have a bunch of candidiates for a floater, from 36 to 52 teeth. I think a floater shouldn't need to have the wheel loosened to pop it in. But I've never used one yet.
I widened the forks with 4 washers at the pivot and 4 more at the spring cage, easy enough, the front is ready to go.
And I completed the chainwheel addon. I can also add spacers or reverse the sprockets to adjust the chain inward or outward if it needs it. The leftover nuts and bolts from the rim braces worked just right.
The big K1 chain fits ok like it sits, no need for washers or spacers if the rear hub lines up.
The chain wouldn't clear the main frame seat tube where it was set, so I have to keep the chainstays in line for clearance and be able to use the twin tire setup. The chain still rubbed the tire so I used the extra nuts as spacers and got the needed space on the smaller sprocket. Just enough threads to make it work.
That's 40/22 gearing, but with all the weight it should be just about right and there's always high gear which kicks in at 10-12 mph if I ever get going that fast. I'll still be sitting low but the cranks will be a few inches higher so it'll be more crank forward with the pedals about 6 inches off the ground. I've got the seat on a regular post for a stand and for test rides. The plan is to have the seat back near the rear tire.
I hooked two chains together and planned on spending all morning aligning everything to get a fairly good chainline. But it lined right up!
The slack in the chain between the larger and smaller chainwheels was too great to make a floater sprocket work. It would have to be huge. So, it will stay on the smaller chainwheel unless the ratio doesn't work out, but I'm fairly sure it will. So that's gear inches of 48 and 65 with the 4 tires, 51 and 69 with the fat tires. Now I'm going to make up a few more braces to make this thing even rattier.
There wasn't a good way to brace up the rear cantilevers, it would have been unstable. So, I redesigned it. The wheelbase was shortened by 3 inches to make it work. But the cantilevers bolt right up to the seat collar on the main frame.
I picked those 2 heavy KMC chains up from amazon while they were on sale last year. Glad I got two of them. Looking at it, I think the rear part should attach just ahead of the seat collar so the chainstays are straight. I'll experiment a little after I go for a test ride tomorrrow. It's ready to go right now, but these aren't the seat or handlebars I'll wind up using in the end.
I took Patty out for a test ride this morning. Heavy. But the gear ratio is just right. I need to tweak the frame extension a little more like I thought I would. It needs to sit lower. But everything worked fine. The steering will take a little getting used to. The seat mount is just about ready to go, but I'll fix the frame extension first. Then I'll make a mockup of the handlebars using some bailing wire. I'll also have all the dimensions written down. Then when the stainless shop makes them up, there should be no confusion. The rear brakes are still in the planning stage.