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Thursday, February 19, 2009

100th Post, Kickstand, Chain Guide

So this is the 100th post on this blog, since September 3rd, 2007, roughly a year and a half-ish. It seems as if I've learned an awful lot since I started out, from being just an average cyclist to something of a bike mechanic. The project itself has progressed and even mutated a bit along the way, branching out from simply adding a motor assist to my existing bike, but actually creating a new bike to handle all the various needs I've pretty much always had, but only in the last couple of years really done anything serious about.

Even cargo pods and trailers are new since starting this project, as I had made cargo pods of various things before, but really only the basket type worked out very well for any length of time, and I had rarely seriously thought about lockable weatherproof pods. Trailers are something I'd wanted now and then, but never enough to do anything about it, until this project--it became necessary to have one to haul larger scrap finds, especially multiple bikes. After finding Freecycle, I really had to have one (and I need a bigger one that can be used as a flatbed style).

It's been an interesting start to the journey of the ultimate electric-assisted bicycle-class human-powered vehicle. I'm sure it will continue for a long time to come.

I built a kickstand today, started before the last rain the other night, but had to stop due to a drizzle suddenly starting. Not safe to be welding in the rain. ;-)

It's simply made from the forward part of the chainstays of the little kid's bike I made the forward tube and headstock of the original recumbent out of, plus a really hard-metal gate hinge salvaged from a wooden-and-chicken-wire gate someone dumped in the alley a few years ago. It's one of those hinges that has the long triangular tab starting about 1.25" wide at it's base, tapering to a narrow rounded end around 5" away (used to attach the gate), and the post-side hinge a 1.5" or so wide plate about 3.5" to 4" tall.

The chainstay was already a very short one (I think it was only a 12" wheel bike, but it didn't have any wheels on it by the time it got to me), and I had cut the dropouts off of it for some other purpose I've now forgotten (might've been for the 24"-to-20" shock fork conversion). The remainder was the part from just behind the Bottom Bracket tube to just in front of where the dropout tabs would have been welded in, just long enough to reach from the new bike's Schwinn Sprint frame's kickstand mount plate to the ground and leave the rear wheel about 1" off the ground, if the stand was left nearly vertical, or to simply hold the bike upright with both wheels still on the ground if allowed to cant forwards a lot more.

The chainstay piece was fairly narrow at it's forward end, and since I don't want it rubbing on the tire when it's retracted (as it will fold up and back to sit against the bottom edge of the bike's actual chainstays), I spread the stay tubes apart at the former seatpost end. This makes it wider than the actual bike chainstays at the rear/bottom end, but about the same at the front/top end, for good clearance on the tire. I used a spring from the junkbox (no idea what it was from) to keep it retracted when not in use. It's simply hooked over one of the hose clamp screws for the seat mount at the top, for now, with the bottom end on the kickstand itself, bolted to it via the threaded hole in the back of the mounting plate that was already part of that chainstay piece.

Since drilling a new large bolthole in the hinge would leave it weak, as it already has the three screwholes in it to begin with, I decided to weld it to the bottom of the kickstand mount plate, first flattening the mount plate's anti-swivel tabs, as they would have been in the way of this large flat hinge, and aren't needed if I'm welding this on. The first step was to clamp the old short chainstay piece in the vise, and clamp the hinge's post-side to the chainstay's BB end, flat against this chainstay's kickstand mounting plate (which I only removed the front-edge anti-swivel tab from), then weld the hinge to the chainstays.

I took some scrap metal bits and welded them as flat plates across the BB ends of the chainstay piece, to give a sturdier end for the bike's weight to lean on, rather than just the bare tube ends. Then I clamped the whole assembly to the kickstand mount plate on the Sprint frame and welded it onto the plate only, but with the long triangular end still on it and bent a little downward to rest against the BB of the Sprint, giving it a bit more anti-leverage against being twisted by the force of the bike's weight (and sometimes mine) when it's down and the rear wheel is off the ground. I also left the end there because the last screwhole on that tab is potentially useful for mounting something (don't know what yet).

After it's all secured, I found a little bit of sideways wiggle in the hinge when it's extended, so I welded on the edges of them just a bit where they fold up against the Sprint's chainstays during use, to make a pair of bump-stops that prevent any wiggle.

The former dropout ends of the kickstand were still open tubing, and really needed to be a bit wider and flat to keep the bike from wobbling about or tipping when on soft surfaces like dirt/grass, though it was nice and stable on concrete or asphalt already. I picked a bit of angle-steel out of the scrap bin; it used to be part of a rackmount ear for something, but had been bent and broken (must've been a LOT of force) and was probably why I'd found it in a junkheap someplace way back when. It was just long enough to reach all the way across the entire kickstand and leave about 3/4" on either side of it, and wide enough to leave the same front and back, so that after welding it on and cutting the center section out (to clear the tire when stowed), I was left with a square pad on each kickstand leg, with a rear-facing softer corner going upward with the angle-bracket edge (this makes it easier to get it to catch on something while parking it, without digging into the surface so it doesn't destroy the surface, especially on tile, carpet, etc, when it must be stored inside like here at home or at work).

Now the kickstand tests fine, and while I did some adjustment work on the derailers and handlebar positions, etc, I sat in the seat directly over the kickstand, on the soft dirt in the yard, and it did not tip over or wobble, and it kept the rear wheel off the ground even when I leaned back in the seat. That is good, because it allows me to test pedal it without riding it anywhere. I verified this works a bit later, when testing out the partly-finished chain guide.

Since I don't yet have the throttle electronics built, there's no need for the chain guide to pivot yet, so I'd intended to just thread the entirety of the former skate axle and tighten it down to hold the skate wheel as rigidly as possible, and also pin the plates together so it wouldn't pivot (basically leaving out all the washers that would have allowed it to move).

I ran into some trouble, though, because it turns out the axle metal is about as hard as the cheap tap & die set I have, so I can't properly thread it. Until I find another shorter axle or bolt that will also fit thru the skate bearing's center tube, that means I can't use the skate wheel as the guide roller.

Junk bin to the rescue again. :-) I found this roller left from the dead treadmill that gave me the motor this bike will use. I don't remember for sure, but I think it had been used to guide the unfolding upright bars and handle/rails on the treadmill, when pulling it out of it's stowed position to it's in-use position. I also think there is another one, but it's not in this junk box, so I probably considered it for use in a project somewhere, and it's still in that project's box. ;-)

It's a heavy-duty but slightly resilient roller, probably nylon, with a VERY hard steel axle bolt that is short enough to mount it on my pivot plates as I'd intended to do with the skate wheel axle (but couldn't since it's threads didn't go far enough down). I verified where the chain will ride on it, and then notched the roller about 1/8" deep for the chain to ride in, using the lathe. Bolted it in so it just clears the bottom half of the chainline, and tested it by sitting in the seat and pedalling in the highest gear combination. It doesn't move or allow chain slippage, so I'd say it'll do as a replacement for the skate wheel at least for now. I don't know if it'll wear any faster than the skate wheel, as it shows no sign of wear after about 20 minutes of pedalling in various gears as I rechecked the derailer adjustments, and just generally played with riding positions and whatnot, while still on the kickstand.

The steering I'm still working on right now, but I did get the bottom tab fully welded to the bottom of the steering tube the handlebars are on. Previously it had had a lot of play because I had tried to thread it on, and nothing I could do would keep it from swivelling, so welding was required to fix it.

Now I have to finish filing out the inner edges of the eyes in the steering tie rod, so the skate bearings will fit inside them, and allow better and more precise steering control, without any play in the connect points.

I've also been painting some of the bike accessory parts, such as the mirror housing and the lighting modules from the Honda, since it was sunny enough yesterday and today to let them dry outside. So they're nice DayGlo Orange now.

I don't have enough DayGlo type paint to completely repaint the whole bike in Orange and Yellow, so it's going to be a really ugly mishmash of colors for a long while, with Orange, Red-Orange, Pink, and Green.

But no one who could actually get a motor vehicle license legally will be able to say they didn't see me coming. ;-)

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