got some more tubes fitted up, and 3d printed a dream crankset for test fitting chainstays. starting to look like the drawing, except in the drawing it seems obvious which end is the front…
6 Likes
I’ve made some more progress here.
I committed to a handlebar/basebar position, its /very/ long and at a pretty forgiving height for me, so there’s a little bit of a “build it and they (the fit) will come” situation going on there depending on the bb height/crank length, but i’m at peace with it. its within the realm of other bikes i’ve ridden or currently ride , and i’m tolerant of pretty wild bar position changes, likely because of my ridiculously long torso, and mid-foot cleat position.
headset seems to work seamlessly. chalking that up as a win, bearing life TBC.
everything is now fitted up and 90% welded out. i’ve had to pause to await an argon delivery. before finishing off all the little tube end caps and bits and bobs. then there’s a few pre-finishing jobs involving a bit of grinding the headset housings to shape, trimming/slotting dropouts etc, before paint.
there is a “direct-mount” aerobar solution going on here which involves a pair of notched in “cups” in the “bar” pictured, with an 8mm through hole. so aerobar position will be adjustable, but involve some ever so slightly proprietary mounting hardware. ill share some images of that arrangement when I have a system to look at, not just some divots and holes.
“THE SLUG” bb heatsink worked well, (solid 68mm aluminium plug) and im feeling very confident about it having stayed round and true enough to give me a decent chance at it working as intended.
8 Likes
also, I’ve finished modelling an appropriately silly crankset and sent a file and drawing for a test part off to have made. this should be a good check if my bb30 drawing (and the machinists work) is good enough. ill report back in my bb30 splines standard thread when I have an update there.
1 Like
tripple post because im pretty excited about how well this worked.
rough because second hand Bushnell, and mystery metal aluminium block, and the bb shell hasn’t been faced yet, but this is feeling pretty awesome; both parts rotate freely without play, and doing that tensioning bolt up binds them tight from my hands with minimal torque.
no way to test yet if its sturdy enough for use, but it feels like it will be, the tension bolt is fine pitch and has heaps of thread left.
im thinking ill drill some holes in the secondary insert and make a pair of pin spanners for counter rotating the two eccentric bits, yet to consider how best to design the witness marks but pondering if they can mostly/partly be on the spanners?
3 Likes
Super cool build
1 Like
a little bit of thread crossover going on here, but the first test crank arm for this bike has “finished” being machined. ironically the splines, which I thought were going to be a sticking point, seem to have passed muster. but the threads opposite ( for the extractor cap ) have been bungled (twice) and the part needs remaking.
before anyone gets in with comments about how the part was placed in the stock, or not tapping the pedal holes in the same setup… I know.
a) It wasn’t me ( im shopping this out to a contractor with whom I have a fairly major language/cultural barrier) and
b) it’s hopefully been addressed for next time.
hoping for a followup part by the end of the week. and all going well, a matching arm for the other side shortly thereafter. but this is Egypt so maybe double or triple that timeline 
also the frame is at the painter.
…and inspired by Em at WZRD and her ludicrous/fantastic wheel choices,I bought a matching set of Zipp disc wheels…
9 Likes
thanks!
frame building in Egypt can feel frustrating and pretty isolated so its nice to have some people following along, and even nicer when they appreciate my efforts!
2 Likes
not really much of an update except;
I almost don’t believe i’m seeing this…
initial eyeball on the spindle and extractor cap interfaces all look as expected, im waiting for some pedal taps; should be in hand early next week. (ill make a guide, and/or start them in a machine tool)
frame is 3/4 painted
everything else is in hand.
maybe (now that its 99% actually in my hands) expect a BAAW in about a week?
5 Likes
I have nothing really productive to say since this bike is so far away from what I am doing… But I absolutely admire your ingenuity to build this almost extra-terrestrial bicycle 
Can’t wait to see it finished!
4 Likes
well,
a rare and unexpected opportunity to get on the track here in cairo arose at short notice so I threw the bike together with the functioning bits i had and went for a rip.
bike definitely goes.
as pictured it doesn’t have the prototype crankset because I couldn’t find a bb to install it in time. but it was super fun to ride, feels great; reassuringly quiet, fast, responsive, stoked. no niggles, no wiggles.
I tried it in anger in both high bb mode, and low bb mode, and it REALLY canged the language. I then wanted to gear-up, and the chain from my old bike was too short, so Ironically, I ended up with the “tweeBB” in middle-back mode, to get the chain to reach .
Im really looking forward to experimenting further with this, Ive approached the Egyptian federation about having more opportunities to access the track and it seems like this might go somehwere… but we will see.
here’s me on the bike
since then, I got hands on a bb, made some decals (the vinyl I could get is terrible quality and is coming off) and put the fancy wheels on, though i’m waiting now on a delivery of tubular glue.
anyway.
here’s some pics of it as it sits. the disc axles are interchangeable and here ive managed to get the front and rear wheels in the wrong places, and the front wheel inside out so the decals don’t line up anyway, but hell.
NB: bb30 spline details over on the BB30 spline thread
19 Likes
It’s a polka dot machine! But what a machine it is! Now, when is it going to attack the 1hr record?
3 Likes
so good…
alright, so a small update;
long story short I was left unsatisfied with the aero-bar attachment system I designed for the bike above; but it was definitely time to get the bike finished, and so i’m glad I did. however, the bike above will stay in drop bar mode, I love it like that, and ill race it in sprint and likely mass start events.
I’ve decided I’d like to be able to actually train some decent volume on a tt bike, and really get the chance to refine and become settled in a position, and then be able to transition it to “track mode” for the season, so…
Im going to take a second pass at a “full time aerobar bike”; this time giving it a more normal carbon fork (one that has a steerer tube) and stem/basebar/aerobar arrangement, because being able to tinker with position using normal parts that other people make (as systems), i’m deciding, is still worth it, also, mounting a front brake simply etc.
i’ll go back to the 130 “track dropouts with a bolt on hanger” rear end, and can make up some little plates that bolt in for 120mm mode. the dropouts I use in steel bikes are only 5mm wide, so the extra 10mm of spacers will be fine on a bolt up track axle.
sram now sells full wireless blips, so thats easy. (by easy I mean i’m going to hell for my battery consumption)
ill almost definitely use an off the shelf TT fork that has a (rim) brake hole.
planning to make another set of cranks/bb the same at this, the bb is an easy win, but cranks-wise, ill take this set for a decent pedal before pressing go on the crank arms. then machining a 144bcd-single-oval-road-narrow-wide-chainring seems like a no-brainer; I wont be doing any hilly tt rides.
ultimately, once its it “track” mode, swapping the aerobar setup for a 200mm, +17’ stem (yolo) to get my sprint position would be a 2 min job, so it could serve double duty on the track if I needed it to, which could be great for travelling to carnivals and not needing to take an extra bike.
expect a very similar arrangement for the frame, except headtube, and I might shave a bit of weight off that downtube…
5 Likes
ok so,
the thinking above led me to put this frame together,
it has no cable provisions, but provisions for a front and rear brake as-well as a removable derailleur hangar. ill put some removable/ unobtrusive cable guides on once i’ve settled on an arrangement.
it has “track-fork-end” dropouts spaced at 130mm (and I have road and track 130mm axles for the disc in the photos) but the idea is I can put some normal rim brake road wheels on it to train with (when in normal circumstances).
still has the multi-length cranks and the same adjustable bb height as the previous arrangement, seems good so far, but still no full-gas experience.
seen here is a 144bcd ‘special’ chainring I made to try and get away with non-round chainrings on the track; I rode it for two race meets, won all 8 races straight across all disciplines, and then I retired it because I was fucking terrified of the noise it made). turned it down to fit an 11s chain and we’ll see how it goes…
so im still /basically/ on the pathway of a full time, track-swappable aerobar bike, but, I had an opportunity to ship some bikes home to New Zealand (sea freight) , and took it. which means they will be there when I arrive back later in the year; lesening my air freight burden (and freeing up some room in our house)
but I have been left with no indoor-trainer-capable bike and thats my training option 6 days a week here ( and I really need to crack on with tsome training) , so this is being pressed into service temporarily as a trainer based “road” bike, please excuse the mish-mash of borderline appropriate parts, (and yes the position is a bit mental, I imagine ill adjust that a bit but thought to try first…) its all temporary measures.
I love the look of this thing, and though the tube selection is pretty out the gate for a road bike, its making me think about a similar setup for a full time road frame; having rebuild my fully internal hydraulic disc 2x12 road bike lately, i’m almost ready to sell it and move back to an external-rim-brake-dedicated-1x11-only-QR offering…
anyway.
new personal CX race bike is next (watch out huttcross M1 midpack operators 2026) , and for me that means 135 QR rear axle, so once thats done, IT can go on the trainer and I can get this thing setup for aerobars and make a decision about cables or wireless (still slow as-fuck-shifting innaproprite for winning road sprints IMCO, also, kinda fuck batteries), and paint it etc.
as stumble across the needed parts ill rig this up with some aerobars and start tinkering with position.
edits, because I can’t help it with the subordinate clauses.
OH, and;
with the tweeBB in the “centre” ( so spindle able to move +/- 13mm up/down, or left/right, or some sinusoidal combination of the each) ) were talking 470mm reach, 488mm stack.
4 Likes
booking flights home to NZ for sometime late October…
first on the block is our club pursuit record, (or more just a personal vendetta between me and a certain round number i’ve never been able to hit) and then all going well, an hour attempt late/mid season (Christmas being mid-summer-season).
2 Likes
well.
again its been a little while, egypt, life, etc, got in the way.
however.
I have
a) finished a couple of other bikes that mean this can stop being pressed into road-bike-trainer duty, its accumulated some sweat rust, but nothing problematic.
b) landed and test fitted a tri-rig aerobrake for clearance in the rear and its a success. its a pretty tight little corner with the minimised chain stay length, 42mm track chainline, and bb over shell thats MUCH larger than usual. I wasn’t really sure what the solution was going to be if it didn’t work, so thats a bit of a win.
c) today soldered on the one extra braze on needed for cable routing for the rear brake, so its time to get this thing painted!
then, it’ll basically time to get this built up in tt mode and start getting comfy.
as a small aside, ive been doing a bit of experimenting with the different crank length options ( on the indoor trainer, with the “road” setup above,) and really feeling like that whole escapade of designing and building the crank/bb system was worthwhile, there are definitely notable differences, and they definitely need further, likely in-situ testing.
footnote.
im still tossing up if having a tt etap setup is worthwhile, anyone got one and have feelings?
5 Likes
I have minimal proper first-hand TT riding with etap/AXS, but having used it extensively on road and gravel I see no downsides except battery levels. Shifting is perhaps not in the uppermost echelons of quality, but it’s pretty good IMHO. Set-up on TT bikes is a piece of cake with wireless blips - tinker with your position all you like and the shifters won’t even notice. Having to buy new blips when they die is a drag, but there are hacks for replacing batteries.
1 Like