Tester's Tandem

Can I borrow it to pose with on the T3?

130mm PCD, won't fit your cranks.

Ah of course. Would fit the Pompino though...

Not really tandem related, but the CentreLock hub interface will work with sprockets down to 12T. 1R8 chain will hit the lock ring or hub shell, but KMC X101 will fit in the gap. Chainline 35.5mm (40.5mm with a Boost110 hub) with the hub in its normal position, but most hubs benefit from a shift to the right to place the rim half way between the flanges, so 40-42mm should work out nicely.

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Does this mean custom sprockets?

Does this mean custom sprockets?

Custom sprockets and a custom hub to build into a disc, ideally :-) There is approximately zero possibility that anybody has the necessary broaching tools to make the parts.

Just thinking aloud and proving that my parametric sprocket model works for values of Z from 12 to 72, at least.

I thought if the mill was going to be cutting 72 teeth, it wouldn't be much more effort to remove some aluminium from the middle and then add some crabon stiffeners on the outer faces :-)

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But this is what I really fired up the CAD to look at, never been entirely convinced by the original 1" fork. Looks like a job for @coldharbour

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I got you Jorj, looks like a fun project.

Two steerer tubes?

Two steerer tubes?

Yes, one for turning left and one for turning right :-)

1" tube inside the head tube, 1⅛" out front for stem attachment. There will be drawings showing everything as I progress, but basically a dog-bone clamp joining the two tubes above the headset where the normal stem would be, then a very short stem below that (in front of the head tube) for the bars, which gets everything low enough to have the fit closer to what I have on my solo bike.

Cool. And then one big-ass spacer under the stem?

Have you thought about yoga?

Unsane

Wow, those forks look great. Do want!

still want a go on this, i know is a bit small for @umop3pisdn, but how small?!

Probably like a 56 on the rear?

if the seat goes low enough that seems doable for a 10 for me....

long and low....

Many assumptions taking place here.

1. Are you using fusion 360? (if so isn't it great? Serious cat umongst the pigeons programme)

2. Going from the grabs, it looks like you envisage straight legs leading to a bent aerofoil crown? If so how do see that crown coming about? I'd have thought machining or casting to cost prohibitive for such a niche item, so if bending, why not bend the leg rather than having a crown and plug? Bending that profile tube would be problematic, but far from impossible...

Are you using fusion 360? (if so isn't it great? Serious cat umongst the pigeons programme)

Yes, yes and yes. NYCCNC on Youtube led me to it.

Going from the grabs, it looks like you envisage straight legs leading to a bent aerofoil crown?

No, its designed as a Unicrown fork, so the legs would be curved. At the moment the bend radius is about 10 times the minor axis of the fork leg, but I'm flexible about that. The idea is to get the legs as far from the wheel as possible as it's likely to be used with a Hed3 at least some of the time.

Oh how I love the erroniously named NYCCNC.

Good, glad it is just me misreading the drawings. Me and Tom still grappling with the functionality of Fusion360, and seem to go completely different routes to get to the same place at the moment. Still a great bit of kit.

erroniously named NYCCNC.

He was properly named when he started off in his bedroom. Next you'll be telling me 22plinkster shouldn't upload 500 S&W shoots to his channel :-)

seem to go completely different routes to get to the same place at the moment

Yeah, Press/Pull seems to be completely interchangeable with Extrude :-)

Until you pan, and that awesome fork you designed looks like a 2d rendition of my fart face.

My forum name is the location of my first workshop. I have no credibility moaning about such things. Fortunately this is the internet, so I will just carry on moaning about it.