ThermionicScott 

So, I had planned to reveal the complete set of updates before RAGBRAI, but ran out of time. Having about 250 miles of shakedown riding first turned out to be a good thing. (I didn't do the whole week this year.)

In a nutshell, my weight-weenie/integration project continues! Mark @gugie brazed centerpull mounts and polished up a set of Mafac Raids for the fork he had already made for me, which allowed the mounting of a superlight custom rack and handlebar bag system that he and Dave Cain (Waxworks Bags) came up with. I can't recommend either of their work highly enough! The new rack and bag shave nearly 1/2 lb off the system weight, and lower the center of gravity of the payload, both pluses for the handling. Here are a few pictures:





Check out the snazzy red accent strips! Velcro strips on the bottom of the bag wrap around the rack tubes to secure it while riding. It's solid!



The handlebar bag is very minimal; it's the wedge shape that Peter Weigle and Dave Cain collaborated on, and this one has no pockets apart from the map pocket on top. It's enough to store a minimal tool kit and tubes at the bottom, a few light articles of clothing, and some snacks. (I like being forced to carry only what is necessary!)



I think Mark suggested brazing a fender support into the front rack, as done by several of the famous constructeurs, but stupidly I said no. So I ended up fabricating a little fender holder out of a wire hold-down clamp. It also helps keep the front end of the fender from shifting out of alignment. If it looks crude, it's umm, a prototype.



I also drilled a hole in the headtube/downtube lug for an internal wire to the taillight. I hemmed and hawed about this step for a while, but figured that it was a pretty strong place to put a hole. I deburred the hole as best I could, and painted it to prevent rust, before inserting that cut-down grommet to protect the wire. I drilled and deburred a corresponding hole through the seat post, and fed the wire in from that direction. BTW, I used a regular audio cable for the wire. It took some doing to feed it all the way through the frame and out the hole in the downtube lug!

I'm pretty pleased with the B&M TopLight Line Small taillight. Once charged up, the standlight lasts a long time. It's fantastic to just be able to pedal and have lights, and not worry about how much time I have left in my batteries -- that was a source of stress on Paris-Brest-Paris I didn't need!



With the changes listed, my bike comes in at 25 lbs as you see it in the first picture complete with fenders, lights, rack, handlebar bag, pump, and the set of tools below! I think that's pretty decent for a 57cm steel frame with no carbon fiber or titanium parts -- I derive a lot of joy when someone picks up my bike and says "your bike is way lighter than it looks."



To be continued...

ThermionicScott 

Some of the weight savings are due to this jewel, and the 215g 107mm Velo-Orange bottom bracket inside. During the spring of last year, I crunched some numbers and bought the Rene Herse crank I'd been dreaming about. In Technical Trials-inspired fashion, I chose small 42/28 chainrings that make good use of the small BCD.



Most sensible people would use a crank like this to get super-low gears, but not I!



This crankset paired with a 7-speed 13-14-15-16-17-19-21 "J" cassette provides very closely-spaced gears in the range from 35" up to 84", with 68" in the middle of the big ring. Perfect. I've gone back and forth on having higher gears than 85", but I really don't think I need them on this bike, and having them tempts me to mash and hurt my knees. Velocio himself supposedly recommended 35-85", and that's been in the back of my mind this whole project: https://www.randonneurs.bc.ca/histor...rd-graves.html

Getting even more into the weeds, Jean Dejeans's bike for the 1948 Paris-Brest-Paris featured a 48/32 crankset with a 16-24T freewheel. My gearing fills the gap in the middle of the freewheel and adds one gear on top. Still, Dejeans finished PBP in under 54 hours, so the lack of tall gears certainly wasn't a problem!



Thanks to @stronglight for his album of info about Jean Dejean's PBP bike! https://www.flickr.com/photos/strong...57618749510933

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So I mentioned that RAGBRAI served as a shakedown for this bike. A couple of days in, I noticed that one of the taillight wires had snapped.



Thankfully I caught this during the day, and bought a battery-powered taillight in the next town just in case I did any riding in the dark for the rest of my trip. What happened is that the center wire in this cable doesn't have nearly as many strands as the outer, and flexing caused it to snap. In retrospect, I should have anticipated that. I cut back the wire and soldered on new connectors. This time, I paired the connectors together to support each other and added heat shrink tubing over them to act as strain relief. Turning the handlebars back and forth, I'm a lot more confident that the wiring will hold up.




(You can tell by the darkening of the clear tubing that I'm not using a professional heat gun for this! )

Another mechanical: on Wednesday, the last day I planned to ride this year, the front brake straddle cable began to pull out of the nutted end. For three days prior, it had done all the braking I asked of it, so this was mysterious. None of us had the required wrenches to tighten it back down, so I decided to end my ride there. Upon getting home, I realized that I didn't even have the necessary wrenches there either! So after a quick order from Amazon for two 9mm wrenches, I was finally set. Good reminder to check every bolt (and have every tool you need) before embarking on a long hilly ride!

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One other note: I am now sold on the concept of wrapping handlebars starting at the brake levers and working outward in both directions. It's more fiddly than starting at one end, but the tape will not curl from riding in any position! The trick is to find some way to secure the tape at the starting point. I used a silicone bracelet and twisted it enough to hold tension on the tape while I worked:



If you've gotten this far, thanks for reading! This bike continues to be a fun project, and I love riding it more and more.

52telecaster

I love your build and on gearing let me say I am not any kind of athlete but have limited my top gears to 90 inches or less for years. I do not need nor understand 100+ gears that folks use. I will say that while mid 30s is my usual bottom in practice I do have much lower bailouts available.
once again, amazing build!

gugie 

MAFAC used some odd sized wrenches BITD. The closed end, thin wrenches that came with their toolkit are perfect for brake adjustment and repair. You can find people selling them online at the usual URL's.

noglider 

Fantastic! So much thought and work went into this.

clubman 

Nice build!

ThermionicScott 

Thanks, Tom! I really feel like the arc of this thread/project shows that "Good judgment comes from experience. Experience comes from bad judgment."

lonesomesteve

I love everything about this bike! Nice job!

And I bet it's the only bike in the world with a Suntour ARX front derailleur combined with a Rene Herse crankset.

ThermionicScott 

Thanks, Steve! You're probably right.

mountaindave 

Man, there are all kinds of interesting ratios in this chart that you managed to duplicate; chainrings are 2:3; the overlap gears are also 2:3; the lowest gears for both setups is 3:4; Jean’s highest gear and your [almost] highest gear are 1:3. You must have had a lot of fun working this gearing out.

Of course it’s 7-speed.

ThermionicScott 

I really enjoy using that page (Bicycle Gear Calculator) to dink around with gearing setups. I also considered a 44/30 crank with a 13-14-15-17-19-21-23 "I" cassette for a smidgen more range in each direction, but ultimately went with "smaller, lighter, and tighter" for now.

At the time I bought the crank, Rene Herse recommended a 110-113mm bottom bracket for double cranks, but by choosing a 107mm, I can use the 42T big ring with the whole cassette as a "1x + granny" setup. The 52"-84" range on the big ring is great for all but steep and/or long climbs.

It's amusing to put that gearing next to any modern bike's, like the new All City Space Horse we just bought for my wife:

Speaking of which, her size (49cm) is usually equipped with 700C wheels, but I asked the guys at the shop if we could swap to 650B wheels for fatter tires and to lower the whole bike slightly. Does that qualify as a 650B conversion?

mountaindave 

Hmmm, not sure disc brake wheel swaps count.

Personally, I don’t see why gravel cassettes start at 11 with a double chainring. Nothing bigger than 13t is needed - 11t wears out so fast and isn’t even round. Can you do a 42/26?

As far as I can tell, the only reason to have an 11t is in a 1X system. I challenge any average person to push a 46x11 on the flats outside of a peloton or a 10mph tailwind. I have a 45x13 high gear on my gravel bike and only use it on downhill sections - and that’s rare.

I could go on and on about the lunacy of modern cassettes. No wonder I prefer my half-step+granny drivetrains (5-speed freewheels BTW )

Retrogrouch-rant over.

ThermionicScott 

Tell me about it! I think 46T is already the smallest big ring you can get for this crank (FSA Super-Mega-Exo-Omega-Something-Or-Other), so I've idly checked to see what other cassettes are out there in the supply chain. If it were my bike, I'd probably snag a 12-25 or 12-28 right away, but we'll see how Tara gets on with this gearing before shelling out the $70...

mountaindave 

The supply chain sucks right now. Combine that with the meager cassette offerings in anything other than a 11t small sprocket and... eBay? At the bike shop, we've resorted to telling customers to source their own parts and we'll install them - we just can't get what they need.