citybike · guv'nor · sturmey archer

The City Bike

Awhile back my wife and I went to Universal Cycles in Portland, and while there saw the Pashley Guv’nor. It’s a stunning black bike modeled after a path racer, which was a track bike first made in the late 1800s. They kindly let us test ride it and it was a lot of fun charging around the neighborhood on it.

Pashley Guv’nor
No head visible but she is smiling widely.
This bike has a Sturmey Archer 3 speed hub, with an old style trigger shifter and drum brakes. Big cream colored 29er tires (700c), a north road handlebar turned upside down, and a Brooks titanium railed saddle. The angles of the frame are relaxed and the bottom bracket is high (12″). Its a pretty simple bike, just get on it and go. The frame is Renoylds 531 tubing, I assume main tubes only and not butted. The seat stays are bolted on, strangely enough. 
It is a loose interpretation of a path racer. It does have the high bottom bracket, slack frame angles, and the handlebars resemble the type found on these bikes over a century ago. However it is not a track bike of course (the path racer is a fixed gear bike); but with its gearing and brakes it’s a lot more useful for getting around town. However, lacking racks, fenders, and lights, this was just the start of a bike I would find useful. It’s like a trophy bike, and I wouldn’t feel right starting to hang lots of accessories on it that it wasn’t designed for.
My wife was ready to lay down the cash ($1700), and I think it would have been a fun bike to own, but I told her I would build her a new one instead, using some of the parts from her old one.
Finished and painted with Canadian geese in the background

I have yet to make the enclosed chaicase, but it will have one. Rear rack is cantilevered off back to avoid heel strike when bags are there.

without front basket. 

The bike was powdercoated by Class Act in Portland. Frame, fork, racks, fender struts, and handlebar stem, all for only $200. Quality work at a great price.

Here is the work in progress before paint. Still needs rear rack and chainguard. That Brooks basket was meant for this bike. It is strapped on the front rack instead of using the handlebar mount it came with.

A few hundred miles or so were put on this bike before we were ready to have it painted.  It takes time to work out the kinks.

I took the elements of the things we liked about the Guv’nor and built them into this one. The flipped over north road bars, Brooks saddle, wide tires (but 26 inch instead), Sturmey hub gearing and drum brakes.

Then I incorporated the lights, racks/basket and fenders. The racks I make to fit out of cromo steel aircraft tubing. Chose the 5 speed Sturmey hub over the 3 that was on the guv’nor because she may need the extra gears. Got it an awesome Civia kickstand and I designed and made a device that holds the front wheel straight when not ridden (see below). Her old bike which she rarely rode is now retired. I hope this one promotes a renewed motivation to ride.

Design considerations
I ordered the frame tubes from henryjames.com  All basic cromo road bike 9/6/9 stuff. The toptube is a 1 1/8 downtube though, and I used mt bike chainstays for the extra clearance. The fork crown would be segmented (just 2 1″ .058 tubes on either side of the steerer) and the dropouts would be what would work best with with sturmey archer drum brakes and hub gears. Frame angles 72 parallel. Top tube sloping down towards seat a little. Fork offset 50mm; this results in a lowish trail making it appropriate for carrying weight at the front of the bike. Bottom bracket height 10.75″ with 559-50mm tires. If I want to use 40mm tires, the BB height is still adequate, but I see no reason to downsize. Running Schwalbe supreme 559-50 tires works great for this bike. A 700c wheel could present a challenge with toe clip overlap, and there is less variety of wider tires available.
The 5 speed Sturmey Archer eliminates derailleurs and makes an enclosed chainguard possible.These complicated gearcases are not as robust as derailleurs but once properly set up I expect a low maintenance and reliable unit. I wouldn’t stomp hard up a hill with this thing though; there are little pieces inside that could break. That is just a fact of life with internally geared hubs (Rohloff excepted).  I found the gearing to be adequate for just about everything. A 36 tooth chainrings pulls the stock 18 tooth cog.
 This drawing in pencil is life size and on a piece of drywall. All the frame elements are all here.The angles and lengths are accurate, although the “ground” is 9 inches below. I can hold the frame tubes against it to check angle and lengths.

Thats a Brooks Hoxton basket. The wood slats are fixed to it with triple chainring bolts. It comes with a carrying handle (which I removed) and a quick release attachment that clamps to the handlebar (that I am not using). Using the quick release limits the load to about 15lbs. I just mounted on top of the rack instead with zipties. The Brooks grips clamp onto the Nitto north road handlebars.

Home-made front rack and fenders. The fenders are made out of 3 thin layers of cedar, glued up with gorilla glue, strapped over a wheel while the glue set. Fork was raked with help from Aherne cycles. Thanks Joseph!

This brass roller for the 5 speed gear cable came from an old roller-cam brake. It moves with the cable and is bolted to a braze-on.

The Sturmey Archer 5 speed internal gear hub (XRD5W)
There are a number of internal gear hubs out there; but after riding the Guv’nor I wanted the new SunRace sturmey archer with drum brakes. The brakes have a smooth progressive feel to them with a lot of modulation. The need for maintenance is practically nonexistent. It is unlikely the brake shoes will ever wear out. They seem to rarely squeak and the weather does not affect them. They are simply awesome.
The gears on the 5 speed however are a different story. I read mixed reviews on the gear performance of these hubs, and figured that I would probably have to learn how to take it apart for repair. The google group on internal hubs had many helpful posts about this. After reading some posts I decided to convert it from its greased lubrication to an oil bath lubrication soon after I got it.
It comes with lots of different accessories that can be used depending on how one would like to set it up. You can have the chain pull exposed, or covered (with an unattractive piece of plastic). Run full brake and gear cable housing, or cut it for cable stops.
I built it up into a wheel and assembled it into the bike. The initial adjustment using the indicator chain visual was not enough to keep it from skipping in some gears. After several tweaks with the adjusting barrel all the gears seemed to work pretty well. But as the cables settled in and I took the wheel off and on, the finicky adjustment intermittently became an issue. If the adjustment was just a hair off, gear 4 would slip now and then. And no matter what I did, the adjustment always seemed to be a hair off…. Sometimes I could get a few miles without a skip or click from the hub, and I thought it may be that I just have to get used to this happening now and then.
After a couple of hundred miles of inconsistent performance, I took it apart. I used the PDF from sturmey and Aaron’s bike repair had a useful page on it as well (look about half way down). A cone wrench was needed to unscrew the right cone. A hook spanner loosened the ball ring rather easily. I made a tool for gripping the notches on the adjustment cone on the left, by grinding an old plier. That plus an adjustable wrench and I had the hub in pieces on a white towel on a table in my backyard in about 20 minutes. Finally, I needed circlip pliers to remove the planet cage assembly. What I saw surprised me; the axel and gear keys were dry as a bone. Its black coating had worn off to a shiny silver surface, but there was no gouging, or any damage to the shifter keys I saw. The planet cage and everything else was well greased though. I don’t think lubing these hubs with grease is a good idea. So I cleaned it up, greased the bearings, covered the gear assembly with Phil tenacious oil, and put it back together. I was careful to adjust the proper length of axel exposure (21mm on the left side).  Then I found that third gear was the same as second gear! Took awhile to figure it out. I left the clutch sleeve spring out. Rolled away somehow. I got on my hands and knees looking for it on the gravel patio. Half hour later I gave up and took a break; only to feel my foot crushing the spring as I stood up.
I straightened it out as best I could and installed it properly. Now I am getting fast at stripping this hub down and putting it back together. The oil bath made it quieter. There were some skritchy sounds from the hub in gear 2 and 3 from the bent spring, but it worked as before. I ordered a new spring from my LBS. It arrived in a week and cost $3. I have to hand it to sturmey archer; you can get the spare parts.

The internals of the hub

The problem of skipping in 4th gear remained, so I ordered a 3 speed drum hub to replace this one. I emailed the US rep for sturmey archer about the issue. He promptly sent me some parts on warranty to fix it. I am very impressed with the support Sturmey provides.
The 3 speed hub has been running like a champ though, and we will keep using it for now. Since it is narrower, I placed the anti-torque washers on the inside of the dropouts. We don’t miss the extra gears much, and the simplicity of 3 gears is nice.

Dropouts are from Paulcomp. Steel, adjustable, and the wheel will never move out of place. The brake torque arm clamp is a nice chromed piece of hardware; no need to make a special braze-on to bolt to.

Fork crown is a cromo tube, 1″ .058. a coin is brazed on either side. The blades are simply mitered and fillet brazed to the bottom of the tubes. This is reminiscent of how the old Raleigh bike forks were designed.




fork end opens forward, to resist braking forces that would try to force the wheel out of a fork with conventional dropouts. These are made by Paragon.


The front wheel will not move side to side with this experimental thing engaged against the downtube. Made out of cromo wire. It is moved into position in a second. The bike can be leaned against anything and the front wheel stays straight. Makes it easy to load or unload the handlebar basket. If I had to choose between a kickstand and this, I would do without the kickstand. But they work very well together.
Here it is disengaged. It pivots on its attachments to the fork crown. Warped washers and bolts with nyloc nuts provide the friction that keeps it where I put it.
That front wheel holder is probably the most interesting thing about the bike. It is reminiscent of the flickstand, but will not keep the front wheel from rolling. However, it can (and should) be used with a fender. I have no idea if this concept is in use on other bikes, but I have never seen anything like this available commercially.

I tried to make a pair of rear dropouts specifically for the sturmey hub. The SA axel just fits in the narrow slot of this, and will not turn. Anti-rotation washers would not be necessary, however other bike hubs would not fit in the narrower slot, so I would be committed to the SA hubs.
 Tragedy struck when the tap broke off when I was tapping the fore/aft adjustment bolt hole. It was impossible to get out without ruining the dropout. A lot of work for naught.  
Here is another failed experiment, wooden chain guard. The glue job on the wraparound pieces is no good.  I plan to make a chain guard out of steel wire and fabric (check this page in a month or 2 for update!).

THE END




 
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