Folding Bikes - Another rebuilt R20 hits the road

It’s finally done, well mostly done, but at least it is rideable at this point. Actually, I don’t want it to be done. I’ve enjoyed the whole process too damn much to see it just end.

I bought the bike from a former LBS owner in Oakland, CA. It was in decent condition and rode fairly well, if a bit stiffly. BTW, this guy had a large storage unit filled to the roof with bikes he had taken in on trade over a twenty year period. Some very interesting stuff in there.

I began this project last fall at just about the same time that I lost my job. Since this meant that I would need to be more cost-conscious I ended up incorporating parts that I will eventually upgrade. I found things at garage sales, CL, eBay, online bike shops and I even bought an item or two from the LBS. A tighter budget made the hunt more fun and creative.

I would like to offer a hats-off to Bicycle Outfitters in Los Altos, CA for their experience and expertise. At critical junctures they helped disassemble, modify and reassemble key components. I’d still have a pile of parts if not for them. Most amazingly, they didn’t look at me like I was nuts when I walked in with half of the frame in my hand. They actually became enthused about helping out.

I had decided to upgrade everything. Here is a parts list of what I ended up using:
-SA 8 spd hub from AEBike laced into used alloy BMX wheel, 36 spoke, Kenda tire from the front wheel of my DT IX
-New 100mm, alloy, basic front wheel from local wheel builder, 36 spoke, Schwalbe Marathon from CL(BF member, BTW)
-Tektro V-pull brake and lever on front from garage sale
-Nashbar caliper brake on rear with a drop bolt ala Sheldon Brown
-A used MTB rear brake lever from a fellow in the South Bay with about 2-300 junk bikes on his property. Just like a pick and pull auto junk yard, I wandered around till I found something usable, of which there wasn’t much.
-New Jagwire brake cables and housings
-New Nashbar 350mm seat post
-Foam/gel saddle from my old MTB, at least ten years old, but still comfy, if tattered
-RST Capa suspension fork from Bike Stop w/ 265mm threaded steerer, Cane Creek S2 headset
-Zoom adj. angle stem from LBS
-Flat bars from DT IX
-UN72 BB with Shimano cups 68x113 from eBay, Sugino 48T chainring and cranks from eBay, chain from LBS
-Hunter Green and Gloss Black paint from hardware store(OSH), DuPont Nason clear acrylic sealer from auto parts store(?)
-DecoColor paint pens from crafts supply store(Michaels)
-Testor’s decal paper from local hobby store(?)

What follows are some of the details about this build. It’s long but hopefully interesting. Read it at your own peril!

The bike came apart fairly easily, even the BB. The LBS pressed out the cotter pins and loosened the BB cups for me without any struggles. The threads inside the bb shell were in great shape, clean and well defined. Disassembling everything else was very straightforward.

As an experiment to see how well this would work, I cleaned up the frame and sanded it to rattlecan paint it. I chose Hunter Green, Gloss Black and Straw highlights to match the colors used on Fords from the late 20’s. I love that color combo on those old pickups. I did the painting outdoors in December and January, not the best time to paint. I even let the paint dry indoors for 3 days. But when I put on the clear coat, the paint crazed in spots. Actually, it would have been more interesting if all of the paint had crazed, it was a cool effect.

I found these paint pens that worked well for detailing at a local crafts megastore . They actually have real paint in them. They are available with different size tips and a lot of colors. Highly recommended.

The UN72 BB I bought on eBay was used. When I started threading the adjustable cup into the BB shell it went in about ½ way and stopped. I backed it out and cleaned and lubed the threads at least 3 or 4 times, but it still did not work. I finally took everything to a machinist who figured out that the cup wasn’t 26 TPI, but 24 TPI. He recut the threads on the cup to 26 TPI and it worked. I even tried the suggestion from one of the R20 sites of grinding the ridge off the fixed cup to give some adjustment on that side, like the Phil Wood cups, but when I installed them I still couldn’t get it to screw in any deeper.

The fork and steerer were a challenge. RST repeatedly promised to send me a threadless steerer, but after 1½ months of waiting I gave up and used the threaded steer with the already installed threadless headset cups. This worked quite well. It’s held in place with the nuts from a Ritchey threaded headset plus a few spacers. The fork, however, is way too springy. Even when braking the front end nosedives. I think a rigid replacement is in order here. It would certainly be much lighter.

The Sugino crank fit well with plenty of clearance from the chain stay. When I first assembled the drive train, the chainline was way off. First I realized I had the rear sprocket reversed. Getting that right helped a lot. But to get it even closer I had to mount the chainring on the inside of the spider arms. Luckily the arms seemed designed for this. Now it’s really close to being straight.

I printed a single “TWENTY” decal using the artwork provided by LitttlePixel. I printed one, applied it and it disappeared against the green paint. I printed another, running it through he printer five times to get more color depth. It still doesn’t really stand out, but that’s OK. It looks good just the same.

I want to thank everyone on the forum that has ever posted anything about the R20. I’ve read it all many times. This bike would not have happened, and I would not have learned nearly so much, without all the freely given advice and info. Thank you all very much.

If you have any questions, please ask.

Here is a link to photos on Flickr.

http://www.flickr.com/photos/paulcstaley/sets/72157604011405932/

That is a might fine looking Twenty...I understand the feeling of finishing something and wishing you could just keep going.

Thankfully... my Twenty still has quite a number of changes I would like to make and I am already looking at building another in a fixed gear version.

Lovely! The colour is just lovely... Great to see you used the decals :) ; I guess that paper is designed for use on top of light paper. One could always get some vinyl cut ones at a later date but the transparent effect has come out pretty nice.

I totally understand the 'wishing it wasn't finished' thing. I think it's the addiction of tinkering that you've been bitten with. My Twenty is sort of finished but there's always something new you can do - or - like me - you can always get another frame and spend spare moments dreaming about what you're going to do with that one.

I had to mount my chainring on the inner too - I think it's a fairly common thing as the BB on a twenty is pretty wide compared to the rear hub.

I wanted to ask how the rear brakes are holding up - I've read and seen about the Sheldon bridge extension before but always wondered if there would be maybe just a bit to much flex in setup to make it useable? I guess the extension bit has to be fairly thick to counter this - what kind of steel have you used? Or is it billet Alloy?

Here is a 'tip' (which you may think unecessary):

I see you have the RST suspension forks on it. So do I. But I thought the geometry is badly affected by the much longer forks compared to the originals. So I actually cut the stanchions shorter. I carefully checked the amount of travel, made sure the crown wouldn't end up too low to it would hit the mudguard at full compression, and calculated that the result is fairly close to original:

Jur, When you say "stanchions" are you referring to the two inner or outer legs of the fork? Then you welded things back together? TI agree, the handling with these forks is definitely not right. The springs in the Capa forks I have are supposedly adjustable, but turning the knob makes no difference. Have you amy experience with this?

Two really nice looking R-20's !

Now I'm not sure our forks are identical... my fork crown has 3 sets of clamp screws in it, one set for the steerer tube and 2 sets for the stanchions (the chromed inners). I was able to loosen the stanchion clamp screws, remove the crown, cut the stanchions and put the crown back on. But I don't see the screws on your pics. You can see them on mine especially the 1st pic.

My forks are not adjustable. They are fairly soft, but I have grown to like them as is. Very plush.

there good looking bikes.

those forks on the first bike look like they are pressed together in the factory and are not able to dissasemble.

Sixty Fiver and LittlePixel - I love having a "good" excuse to spend my money! I still peruse Craigslist on a regular basis looking for parts. The S F Bay Area is very bike savvy with lots of high priced bikes about. So, decent parts show up fairly regularly, but the prices can be all over the map. This project was also a very good thing to have while unemployed. Between searches and interviews I had something positive and challenging to look forward to.

Jur and AlecW - The stanchions on the fork I have are pressed in, so no easy fix there. I will need to ride it for a bit to see if I can live with the funny steering and the ride.

LittlePixel - I used 2 pieces of 1/8" Aluminum separated by appropriately sized nylon spacers to make the drop bolts. I haven't ridden it a lot so I can't address the issue of longevity, but the brakes sure work well. These are inexpensive, good looking, functional brakes. I seem to remember ordering "long reach" brakes, but even at full extension on the pads the brakes barely clear the wheel. The new Tektro R556 brakes with really long reach would be a better choice now. I have ordered a set for another build and will post photos when they arrive.

I have added two detail photos of the rear brakes to my Flickr account, link below.

http://www.flickr.com/photos/paulcstaley/sets/72157604011405932/

I just had a look at aebike's forks, looks like the one I have with the 3 sets of pinch bolts has been discontinued. Pity - shortening the stanchions is a valuable improvement. Perhaps the same can be achieved from the opposite end?

For the Wasp I used Sheldon's idea of the drop bolt for the rear brakes when using Shimano 105 brake calipers, but it does look sort of junky, so when I finish the other R20 for the missus, I'll pull the Wasp apart and mig weld a proper brake bridge in place for the 451 wheels. While that's happening I'll mount the front Derailluer, have 44/48 chainring configuration, then mig a rear hanger on the drop out for a chain tensioner, then try and make the Wasp a 2 x 8 spd SA hub. Change the front stem to a swan type, use MTB flat bar with Origin 8 drops bar ends so I can easily mount the SA 8 spd shifter on the right and a 2 spd shifter on the left, that should complete stage 3 on the rebuilds.......now to start dreaming of the Rohloff hub in stage 4.;)