Raleigh RX24 - 24" Kids Road/CX Bike Project

Constraints breed creativity.  Or so they say.  Well, my bike storage is quite constrained.  And there are these growing kids with bigger and bigger bikes -- and expectations that they get to share that limited space.  So, while being constrained to 3 bikes sounds an extravagance of 2 (or 3) bikes to most of the world, it has made me hone those choices to maximize the range of cycling activities I'm equipped to enjoy.  I still change things around every now and then, but I've pretty much figured out (and designed) exactly what I want.  And so, if changing my own bikes doesn't sound at all appealing, how do I find outlet for my desire to fritter away time and money researching and sourcing bike components for exciting and different bike builds?  The kids' bikes, of course!

My older son has been saying (or said at least once, which was all it really took to seed the plan) that he wanted a road bike.  And he's agreed to give the juniors cyclocross team a try when that becomes an option next year (we suggested that he needs to pick something one sport-like thing to do for extra-curriculars next year, and this was the least offensive to him).   We might be a year and a size of clothes away, but it's obviously time to start on that road/cx bike project!

The Field

There are a few road bikes for kids.  Specialized Allex, Felt F25, Scott Speedster 24.  But if this really is to do dual duty, it needs to be a CX bike (have clearance for 'cross tires).  And, so this rules out the road bikes.

In the world of 24" kids 'cross bikes, there are also a few options.  Most have rim-brakes, but there are a few disc-brake options.  (Disc brakes are pretty much a hard requirement for me on this bike, for reasons that will become clear.)  But standing out head-and-shoulders above the other options, value-wise, is the Raleigh RX24.  So - spoiler alert - that is what I bought.

(Here's a good survey of kids CX bike options: https://rascalrides.com/the-best-kids-cyclocross-bikes/)

Project Overview

So for most people -- smarter, less frivolous people -- adding the $340 RX24 to cart and having it arrive 2 days later (Amazon Prime), would be the end of the story.  The bike, after all, has a solid set of components spec'd; it doesn't really need to be changed at all.

That's boring.

Surely we can find something that "needs" changing.

The highlights of what I set out to change / improve:

1. The wheels -- and the wheel size.  Not only build something that will be better and lighter, but rethink the wheel dimensions to work better for a road-bike setup.
2. The brakes.  The stock brakes would probably be fine, but for smaller/weaker hands, I'd like to improve the braking performance.  Especially if thinking about road speeds.
3. The drivetrain.  Switch to a drop-free 1x setup.  Expand the gear range and top-end speed.

And a sidecar goal to these overhaul changes was also a desire to reduce weight.  At claimed 21lbs (actual 22lbs, w/o pedals) this bike isn't excessively heavy, but I think is a few lbs heavier than it should be.  And when that's 1/3 of your body weight, saving some weight makes a noticeable difference.

And of course to do this all as economically as possible.  It's coming out of my fun-money account, which means these things have to compete with other bike-related purchases.  Informally my goal is to get this to something that is comparable (in terms of features, maybe weight) with the Isla Luath 24 Pro Series, but costing significantly less.

The Wheels

A tangent on wheel size

So, there are actually two different, incompatible wheel sizes being used to refer to "24-inch" bicycles.   The definitive online reference on this is Sheldon Brown's page, but the short-version is that we have bikes like the Isla Luath 24 that are using the kids mountain-bike 507 ETRTO size and bikes like the Raleigh RX24 that are using the British youth 540 ETRTO size. ... Also shared by wheelchairs.

That 540 size is pretty tricky if you actually want to find tires.  Well, other than wheelchair tires.  And this difficulty provided inspiration for one of the key goals of this bike project.

Can we change the wheel size?

Since this is a disc-brake bike, there's nothing stopping you from running a smaller wheel (well, almost -- see below).   The ETRTO number refers to the diameter between the bead shelves on the rim.  A 540 (mm) ETRTO is obviously quite a bit larger than a 507mm ETRTO that is the more common size, so putting smaller wheels in this frame is certainly an option.   But frames are designed with bottom bracket drops/heights for a specific size wheel, so while it may work fine in theory, in practice it might increase the risk of pedal strike (pedal hitting the ground when turning) if you drop the bike by 16mm ((540-507)/2).

There's another option, which would be fitting larger wheels in the frame.  As it turns out, the very common 26" MTB wheel size is not that much larger -- its ETRTO is 559mm.  So 9.5mm increase in radius.  But for a road tire, that might actually work out perfectly.

The nominal size of the stock tires is 37-540  (37mm tires), which theoretically indicates an overall diameter of:

37 * 2 + 540 = 614

If I were to fit a set of 28mm road tires on 559 rims, the theoretical diameter would be:

28 * 2 + 559 = 615

That's pretty close.

In practice, though, nominal tire sizes and measured tire sizes are only loosely related, so this isn't quite as cut and dry as it looked on paper.  (Spoiler alert) In practice everything measured smaller than claimed, so the new wheels are maybe a few mm bigger -- but it all works out just fine.

The Wheel Build

I'm always looking for an excuse to build wheels, so this is certainly a fun part.  Sourcing parts for a 26" road wheel (esp. w/ quick-release dropouts) is actually really easy.  For one thing evolution of trends plays into this nicely: older MTB rims were quite narrow by modern (MTB) standards -- and looked much more like what are now being sold as road-width rims.  And the using QR for disc-brake wheels is definitely a thing of the past, so it's quite easy to find hubs on clearance, etc.

Most 26" (MTB) rims, though, do tend to be drilled for 32 spokes.  I really wanted a 24-spoke wheel.  This is a road bike, after all.    Luckily there were some lightweight rims drilled 24h and 28h for XC racing.  I picked up a set of 24-hole Sun UFO rims for $50 shipped; these are eyeleted rims which weigh around 370g each.  For hubs, I turned to BDOP cycling clearance bin and picked up a Novatec D612SB and D711SB hub for around $70 total.  I laced these up with Sapim Laser spokes.  At 1377g, they are certainly some of the lightest "normal-sized" wheels I have built.

So, that wheel build was very economical [by wheel-build standards, anyway!], I ended up going completely off the deep end when it came to tire choices.  To be fair, the options for road tires in this size are fairly limited (though vast in comparison to the stock wheel 540 size).  After looking at ~$50 prices for a Schwalbe Pro or Conti Grand Prix tire, I ended up buying $78 Compass Elk Pass tires, which are absolutely the nicest tires any 26" road wheel could have.   And completely excessive.  But I kinda love my Compass tires and I'm happy to support this smaller outfit.

On these rims, which measure 17mm internally, the 32-559 Elk Pass tires measure around 27-28mm high.

I also picked up a set of the Isla Greim 26 tires for when this swaps to 'cross season.  On these rims these 31-559 tires measured ~30mm wide and~29mm high.

Tire Clearance

As hinted at earlier, the nominal size of the stock tires (37-540) was larger than they measured (closer to 32mm), but in the end even the Isla CX tires fit fine  Here are a few clearance photos with the Compass tires:

10mm of side clearance in chainstays.

I used some 10mm-thick rubber tracks to provide a visual on clearance.

Demonstrating that ~10mm of extra clearance exist at seatstay.

Plenty of room in fork.

Demonstrating clearance at chainstays (bike is upside down).

And here are a few with the Isla/Greim tire:

~8mm of clearance to the seat tube.

~8mm clearance from chain stays.

Photo of chainstay clearance.

So, these both fit quite comfortably, which is great since they should address the complete set of purposes for this bike.

The Brakes

If money were no object, I would have replaced the SRAM brake/shifter levers with a full-hydraulic 1x setup.  But that would be a $400+ investment, and that seemed a bit much even for me.  Plus, even though they offer reach-adjust, the SRAM road hydraulic brake hoods are really big for someone with such small hands.

At first I considered TRP Spyre calipers, but in the end decided that these probably weren't going to offer much of an improvement in braking over the stock Promax 300R calipers. 

I then turned my attention the cable-actuated hydraulic calipers.  These should provide better bite than stock calipers but would work with the existing SRAM S500/Apex lever set.  The TRP Hy/Rd was an obvious choice, but upon further research discovered the Juin Tech R1, which was not only cheaper but also was quite a bit lighter (as light as TRP Spyres).

The Juin Tech R1 calipers are also rebranded as the Yokozuna Motoko -- and I found a set of these  domestically for $160, which was quite close enough to the $150 that the Juin Tech R1 cost -- plus they would include the notoriously good Yokozuna Reaction housing (which sells for $75 by itself).

I did order separate Avid HS1 rotors, though.  The Avid rotors offer excellent stopping power and they're inexpensive (I got them lightly used on ebay for $20 for the set, though Amazon also has them new for not much more).

I haven't actually ridden this bike, but from what I can tell these do a great job stopping the bicycle.  I gave my son instructions for bedding in the pads/rotors; I think he followed them.

(I should probably mention that the brakes added a little net weight to the bike.  The stock Promax 300R calipers were around 130g, compared to the 142g for the Motoko calipers.  But the point here wasn't to save weight, but to improve braking.)

The Drivetrain

The goal was to expand the gear range, move to a modern 1x system (drop the bash guards sandwiching the front ring), and reduce system weight.

The stock bike came with a 32t chainring and an 11-32t cassette.  I found a lightly used XG-1080 11-36t cassette on ebay for under $80, which is a lot for a cassette, but they aren't quite wear-and-tear parts on kids bikes.  I paired that with a Deckas 38t, narrow-wide chainring.

And swapped out the Apex WiFli rear derailleur (max 32t cog) for a used SRAM GX short-cage, clutch rear derailleur (max 36t cog).

So we moved from a 291% gear range to a 327% gear range, while lightening up the overall system and quieting it down (from chain slap).

Other Odds and Ends

I found some used Bontrager 38cm carbon XXX bars on ebay for $40, which weighed about half of the stock 36cm bars with compact drop/reach.

The 60mm Uno stem didn't save much weight, but I had it on hand, and I like them.  (I've actually ordered a 40mm Wren stem to pull the bar in a bit, so I'll swap that in when it arrives.)

I kept the stock cranks, but replaced the square-taper bottom bracket with a "Week Eight" titanium + alloy model available on ebay for $39.  Generic square-taper bottom brackets are ridiculously heavy.

For the saddle, I did some research and settled on the WTB SL8 as a good option to anatomically fit young riders (narrow and not too long).  At $90 this was one of the more expensive components, but it seemed like a decent investment.  The stock saddle on the RX24 is probably one of the worst parts of the stock spec.

The seatpost is a Hylix 27.2mm carbon post.  Quite inexpensive on ebay/aliexpress.

The Final Product

I'm really happy with how it turned out.  The wheel size upgrade is a huge win for tire options/versatility -- and the wheels are much lighter.  The brakes are a nice improvement (or so I'll just have to assume based on all reviews) while using the existing levers and the drivetrain is expanded and lightened up.

Ready in all his mountain-biking gear to test out this road bike!

In terms of the weight savings, we got the bike down from 22.0 lbs to 17.3 lbs (both weights w/o pedals).  My son helped me do some part weighing so we could see what were the biggest wins weight-wise.  This is obviously not comprehensive, but there were a few surprising items.  There are certainly many places to save further weight, if someone were so inclined (and less budget constrained) -- e.g. the crank arms.  Unfortunately, there's no option that I'm aware of for a 3rd party carbon fork at this size; that would likely save significant weight.

Part	Stock Part Weight (g)	New Part Weight (g)
Stem	115	91
Saddle	321	189
Seatpost	294	156
Bottom Bracket	305	135
Cassette	329	213
Rear Derailleur	208	266
Handlebars	356	181

This was a fun project.  I don't think there is anything at this point that I would do differently, though certainly if I wasn't trying to stay in any sort of budget, I would have found a way to do full hydraulic brakes.  As it is, my son still isn't comfortable using the brakes from the hoods; it's just not enough leverage to quickly stop the bike from there.  Hydraulics, if he could fit his hands around the larger hoods easily, would not have that problem.  But he is happy to use the drops and I've positioned the bars a bit higher / less-aggressive to make that more comfortable.

Waltly Titanium Disc-Brake Road (Race) Frame

A couple years after I built up my FM166 (described in posts one, two, three) carbon disc road bike, I decided to change things up once again and replace the frame with a titanium frame.  Yes, a frame that would weigh more, cost more, and probably be no more comfortable to ride.  I have really enjoyed this foray into carbon, but there is definitely something I really like about riding metal bikes.  I do love my [titanium] Habanero commuter "cx/touring" bike to death.  (Literally: it has died twice; I'm riding my 3rd frame, all wonderfully replaced under warranty.)  That is a fantastic multi-surface bike, but I also love my road (race) bike, which happens to be carbon.  Sometimes it's nice to ride something purpose-built for going fast on pavement.

While I love the handling of my road bike, something about the carbon frames has never fully made peace with me.  I don't know if it's the hollow plastic sound when road debris hits the bike or just a personal aesthetic preference for the simplicity of welded tubes.  I take a lot of pleasure with the tangible, mechanical nature of the bicycle as it contrasts with sitting in front of a computer all day, so I suspect this is more about the constructed aesthetics than anything else.  I guess I'm a little bit hipster like that.

So, I set out to build (have built) a titanium frame that would synthesize modern frame features with a more classic frame aesthetic, and with road-race geometry.  Disc brakes, new dropout standards, round straight tubing, 73.5/73.5 angles, short-ish chainstays, etc.

Choosing a builder

I decided early on that I'd have this built by one of the mainland Chinese titanium builders.  I can't bring myself to spend more than $1k on a frame, so that was really my only option if I wanted a custom titanium frame.  There are a few players in this arena that will deal direct to customers, most notable are XACD, Titan Product, and Waltly Titanium. 

The key to helping me decide which builder to use (and really the key to getting into this project at all) was Andrew's www.spanner.org.uk blog.  I traded a number of emails with Andrew both while choosing factory/fabricator and then for comments on designs and to share final result.  (Thanks, Andrew!)  Update: Andrew just published his own account of this build.

After getting initial quotes from XACD, Titan, and Waltly, I ultimately decided to go with Waltly.  Waltly was not the cheapest option (that would have been Titan), but they left me with the most confidence in their ability to produce the frame I wanted.  Of the three only XACD was willing to work with butted tubing (for additional cost), and while that was originally something on my list I decided that it wasn't a requirement to save a couple hundred grams (and my Lemond Victoire that had butted tubing did have a few dents in the tubes, so straight tubing seems like a more robust answer).  I would consider using XACD in the future, though their sales rep, Porter, is quote notorious and they way they charge extra for every frame feature would have made this frame a fair bit more expensive.

What to build?

At a high level I knew I wanted a titanium road disc frame with a race-oriented geometry.  I provided a basic set of features I was looking for to get the original quotes (since some builders charge extra for some of these features).  But I was also open to changing specs depending on what the builders could offer for dropout design, cable routing, etc.

Frame Features / Design

My basic requirements:

• Disc brakes (of course!)
• ... but newer flat-mount disc brake road standard
• 142x12 rear dropouts
• 44mm head tube for tapered fork
• 27.2mm seatpost
• Threaded (BSA) bottom bracket

And my high-level design goals were pretty basic:

• round tubes
• straight tubes, clean lines (so some internal cable routing, probably)

Geometry

One upside to changing my road bike frame every year or couple years is that I've had a lot of experience riding different frames.  And I've had a bike fitting which basically confirmed that experience.  For sake of simplicity, I knew that my current carbon frame is configured with a good stack/reach setup for me.  I then used the excellent Stack and Reach Calculator spreadsheet to plug in my current frame and stem/spacers setup and then find measurements that would work well for the new frame (a slightly steeper seat tube angle fits me better, so that needed to be factored in too).

CALCULATE BASED ON GEOMETRY
GEOMETRY	FM166-58	Ti	DIFFERENCE
TOP TUBE LENGTH (EFF)	581	580	1.00
HEAD TUBE LENGTH	175	175	0.00
HEAD TUBE ANGLE	73.5	73.5	0.00
SEAT TUBE ANGLE	73	73.5	-0.50
BB DROP	68	68	0.00
FORK LENGTH	369	369	0.00
FORK RAKE	43	43	0.00
STEM LENGTH	110	110	0.00
STEM ANGLE	-6	-6	0.00
SPACERS + HEADSET + STEM STACK*0.5	39	43.26	-4.26
STACK	576.36	576.36	0.00
REACH	404.79	409.27	-4.49
STACK WITH SPACERS	613.76	617.84	-4.08
REACH WITH SPACERS	393.71	396.99	-3.28
STACK WITH SPACERS + STEM	633.80	637.89	-4.08
REACH WITH SPACERS + STEM	501.87	505.14	-3.28

After providing the various frame measurements, I also indicated that I'd be using a Whisky No. 9 fork with a 367mm axle-to-crown length. I wanted to call out that I'd need the head tube angle/length to compensate for the fact that I'd have an extra 14mm lower stack height on account of the external (Hope) headset lower bearing.

Lower bearing stack height matters.

Adjusting so that the effective angle would be correct despite additional stack height under the head tube wasn't something that I had fully appreciated when starting this project.  But as you can quickly tell using the bikegeo.muha.cc calculator, adding 15mm to the effective axle-to-crown measurement of a fork makes a significant difference in the effective head tube angle.

Other geometry dimensions (BB drop, chainstay length, etc.) were based on my current frame.

The Process

My sales rep at Waltly was Amy Lv.  She was very courteous and communicated very well and very promptly (obviously there was a timezone difference, so typically email exchanges would take 24 hours).  There wasn't a language barrier per se, but I did learn that it was most efficient to be as clear as possible (and use standard/non-idiomatic vocabulary and phrasing) and include example photos or drawings to save back-and-forth emails.

But there were still a lot of emails, even when there was no misunderstanding.  Around a hundred, last I counted.   My own indecision was in no small part to blame there.  Also, an important thing that Andrew (spanner.org.uk) relayed early on was that these builders are more fabricators than designers.  They will happily make small design decisions to fill in unspecified gaps, but typically they will implement whatever they are told to implement -- even if it is a bad design.  This is probably the biggest risk with building a Chinese custom ti frame.  So I spent a ridiculous amount of time looking at other frames for ideas and reading the endless debates over the structural value of chain stay and seat stay bridges, etc.  This all made me decide that someday I'd like to build my own frame -- probably with steel.

So first step was to work with Amy to specify as exactly as I could what I was looking for.  I ended up also sharing with her a requirements/specification document to help me keep that growing list of specs organized.  It was also a useful way to embed photos/diagrams and seemed to work pretty well as a means of enhancing email communications.  Once we had specified everything, it went off to design department.  Within a couple  of days I had the first design back.

Version 1

So that looked like a good start.  There were a couple of things that had gotten lost from requirements, though, and a couple of things that I had requested but were impossible with my design.  And I was talked out of such a small gauge down tube by Andrew -- and then this was reiterated by Amy. (At first I suggested that the 31.8mm downtube on my Habanero was just fine, but this argument was blunted a bit by the fact that my Habanero down tube cracked after 25k miles...)   So changes to this design included:

1. Straight 44mm head tube (not a tapered head tube).
2. Larger 40mm down tube.
3. Straighten those chain stays! -- which meant lengthening to 415mm and decreasing tire clearance.

This came back quite promptly in the second design iteration:

Version 2

This looked much better, though I started worrying about the internal routing -- and specifically the gaping hole to accommodate 3 cables (housing) exiting near the BB.  This didn't seem wise and I wasn't entirely sure that they had run any sort of structural integrity calculations on this.  So after many different design iterations routing internally through various tubes and moving around caliper mounting etc. (mostly just iterating to myself, luckily), I settled on the obvious option to run the brake housing/hose externally using zip-tie mounts and internal routing for just the derailleur cables.  In the back of my mind was the idea that if I drop my FD at some point I'll just route the brake internally making it a bit cleaner.

So after that was worked out I had the final version:

Version 3 (Final Verison)

I also requested a sandblasted logo (on the otherwise brushed ti frame).  I didn't actually have a design, but in an effort to have my frames be more forthcoming about their origins, I asked them to "paint" the Waltly logo on the head tube and the company name in Chinese characters (that you can see in the design document) on the front of seat tube.  They were a bit suspicious as to why I wanted their name on the frame, but I explained that to me it just made sense since they were the ones building it.  Of course, later I saw that for bike shows they have a standard branding they use on their frames; I would have just requested that had I known it existed.  Adding the sandblasted logos added $30.

A rough attempt to communicate desired logo placement (on a generic frame)

Once all that sas settled, I approved the design and paid the 50% deposit (so a bit over $500) and it entered the production pipeline from which it was estimated it would emerge after 35-45 days.

Result

After just a bit longer than estimated time (frame was finished but logo sandblasting added a bit of time), I received a bunch of photos of the finished product, all staged against a beautiful shrubbery. 

Obviously one can only tell so much from photos (e.g. was it built to spec? any issues with head tube or BB threads?), but it looked good to me so I paid the remaining 50% of balance and received the frame 5-7 business days later (shipped via EMS).

Despite knowing this would not be a weight-weenie build, I still of course had to weight it immediately upon receipt. Our kitchen scale has weighed many more bike components than food products.

Well, that was heavier than I had expected -- I think the original estimate (but before we had really nailed down lengths and dimensions) was 1300-1500g.  So for a big frame with relatively large, unbutted tubes and flat mount, 44mm HT, etc. I guess this is probably just how it is.  This is ~750g heavier than my carbon frame.  Which is about the weight of one full bottle.  So now I know at least how much weight I need to lose before I can complain that the bike is slowing down my hill climbs.

I had accumulated all the little bits I would need to move parts over from my current road frame (e.g. headset, FD clamp, flat-mount to post-mount adapters, new cables/housing).  So it was a pretty quick job to swap it over.

Most importantly, though, the frame built up perfectly -- no issues with ovalized head tube (had read horror stories, but not with Waltly), no issues with BB shell, rear dropout, or caliper alignment. No seatpost slipping.  And the final bike is exactly what I wanted.  I did not try to take my own measurements of the tubes or angles, but everything seems to be correct (and fit was exactly right, compared to other bike).  Waltly did an excellent job building out exactly what the final design indicated.

One of the first rides.

(I was actually riding on the road adjacent to this trail.)

And a few detail closeups:

142x12 thru-axle dropouts

Internal cables exiting (and un-crossing) near BB.

Internal cables entering near head tube and externally routed brake cable.

The logo effect is subtle (and hard to capture in photo), but I think looks great.

Ridden

So having now ridden it for a few hundred miles, I can say that I'm definitely enjoying it.  At first I noticed that it was heavier than the carbon bike, but now that I have nothing to compare it to, I don't notice that anymore.  It's plenty stiff in the bottom bracket.  I did not notice any flexibility, though I'm sure that if I jumped on a stiff carbon bike I could tell the difference.  I love the way the metal frames ride over the road, though; it feels very solid, which is great.  The rear thru axle is really nice.  Not sure I can tell a difference in stiffness, but being able to mount the wheel while in the stand (without needing to recenter it in dropouts while on the ground) is a nice perk.  No creaks anywhere is nice too.  I hope this frame will last for a long time.  Andrew had (has) some concerns about the internal routing (adding holes to highly-stressed areas of a frame); I guess time will tell.  This is an area (one of many) where I wish I understood the physics at work here better.

Lessons Learned

I don't have any regrets with this frame.  Sure, a titanium bike is heavier than carbon, but to me it feels like so much more of a bicycle.  And Waltly did a first-rate job building to match the drawings.

There was, however, something I overlooked in the final drawing; I had intended to have the rear derailleur cable stops under the chain stay be simply zip-tie stops instead of traditional cable stops -- primarily because I wanted to run full-length housing.  This was always "wrong" in the drawings and I only noticed it after that part of the frame was complete, so it's no one's fault but mine.  That said, I think I prefer the traditional stops in the end anyway -- and this isn't my rain bike, so having the full-length housing is a bit unnecessary.  I was thinking that zip-tie stops would look better when someday I move to eTap and get rid of the cable .... but that's probably a long, long time away (and I can always dremel off the cable stops if it bugs me).  So the lesson there is just to check every single detail of the design multiple times.  It boggles me that I missed that on 3 designs, but then it's a pretty subtle drawing difference between the zip-tie stop and the traditional full cable stop.

One "lesson" that did come out of this is that I should have been clearer initially with regard to chainstay spacing and not talk about the more indirect measurement of tire clearance. I originally requested clearance for 30mm tires (with intent of having option of running a 28mm tire on a wide rim).  The v1 drawings indicated 46mm of spacing which seemed to be way more clearance than I needed (especially with no fender mounts); I was expecting maybe 5mm of diameter wiggle room (above requested tire clearance size) since there are no fender mounts on this frame.  When I backed that down and just asked for 26mm clearance, I still have a frame with 42mm spacing, so I suspect I could comfortably fit a 32mm tire in there if I were so inclined.  While right now the idea of even 28s seems a little redundant with my commuter/cx/gravel/adventure bike, it's nice to have the option.  So clearly there was a very large (16mm) markup when translating "tire clearance" into "chainstay spacing".

Next Steps

Next up, the groupset is getting an upgrade to hydro disc -- and flat-mount calipers.  I'll probably try a new Hongfu flat-mount 12x100 fork I have.  And I'm currently planning to switch to a 1x system (50t ring with 11-40t cassette), though I keep wondering if that is really the right move for this more purpose-built bike.

If (when) my Habanero adventure bike breaks next, I will strongly consider getting another Waltly frame to replace it.  I have loved my Habanero frames, but I really want the versatility to use a tapered fork (the vast majority of disc-brake cx forks are tapered) and if the next break is also at the down tube then I think I'll have enough data points to suggest that a larger down tube would suit my riding style better.  I might also design that frame around a different fork spec (e.g. a suspension-corrected 26" MTB axle-to-crown length) so that I could have flexibility to run 2.1" or larger 27.5" tires.  Hmmm ... sounds like I have already started my next project :-)

Update

A little while after writing this, I switched over to a new flat-mount fork from Hongfu:

HongFu FK-079-F 12mm thru-axle road fork.

And, more significantly, Force1/Force22 hdyro brakes/shifter.  The new fork is really nice.

I have been enjoying this new bike immensely.  It still feels heavy when I pick it up, but I enjoy the ride.  It is plenty stiff but plenty comfortable.

I did decide to replace my commuter/gravel/cx frame!  The requirements took a bit of a twist, but I'll write up a blog post on that shortly.  (I'm working on the build now!)