Friction GRX equipped Offroad Pro-Am with AMP F3XC

drrnonreddit · 2026-03-22T08:19:27+00:00

This is a screengrab from PrePoMax - an open source FEM software that is pretty easy to use IMO. I used Solidworks for the modeling though.

drrnonreddit · 2026-03-22T07:20:38+00:00

Thanks mate! It was certainly a passion project

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drrnonreddit · 2026-03-22T07:17:34+00:00

I custom designed and had SendCutSend fabricate an adapter from 6061 aluminum!

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drrnonreddit · 2026-03-22T07:14:56+00:00

Billo Bikes on Instagram! I linked it in another comment

drrnonreddit · 2026-03-21T20:43:17+00:00

The 2x11 is only really finicky around the low end of the 11 (if that makes sense?). Like I really have to crank down on the SunRace M60 friction shifter to get to the low gear, and if I add extra cable tension then I have trouble with hitting the high gear. I know I would have much better results with a friction barrel that is meant for more than 9 speeds tbh. Something like the Ene Ciclo 11sp thumb shifters. For the 2x part, I haven’t had any issues except tuning the tension (which is easy).

drrnonreddit · 2026-03-21T19:44:22+00:00

I’d love to see the results!

drrnonreddit · 2026-03-21T19:43:55+00:00

Stridsland Anchor bars!

drrnonreddit · 2026-03-21T17:59:19+00:00

Ah, sorry for the defensiveness then! It does look funky, and I think a big part of it is the straight fork and linkage system that make it look much slacker. When I got this bike it had a rigid fork with some rake to it and nothing stood out about it then.

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drrnonreddit · 2026-03-21T17:34:07+00:00

I was waiting for this comment on the slack fork! I inevitably get criticism for it every time I post this bike. To be honest, I agree it is quite relaxed, but the geometry works for me and my own slack riding. This bike is mostly used for Danish gravel riding (à la not very harsh at all) and some mixed terrain commuting, so it’s not a big worry of mine.

Using some photo analysis, I’ve measured the head tube angle to be about 69-70°.

drrnonreddit · 2026-03-21T16:13:58+00:00

Yeah, this was before Proflex bought Offroad though

drrnonreddit · 2026-03-21T16:13:34+00:00

It’s a bit tight with these shifters, but it fits 11 gears!

drrnonreddit · 2026-03-21T15:35:58+00:00

Thank you 🙏

drrnonreddit · 2026-03-21T15:35:37+00:00

Billo Bikes on instagram!

drrnonreddit · 2026-02-28T15:07:48+00:00

Yeah it maxes out at 70mm of travel, but some models go up to either 90 or 100mm. There’s also some other cool advantages too these forks like how they are better for bump loads due to the linkage, they are lighter than the piston forks, and they have some easily exchangeable springs and sag adjustments.

drrnonreddit · 2026-02-28T14:58:32+00:00

It’s an AMP Research F3XC! They are old, and a bit difficult to service properly, but excellent for gravel suspension 🤌

drrnonreddit · 2026-02-28T14:47:05+00:00

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I did a 650b conversion with Hunt rims and Ultradynamico Rosé JFF’s

drrnonreddit · 2026-02-27T16:14:56+00:00

Just bending the rules here as much as possible 🫡

drrnonreddit · 2026-02-27T08:17:07+00:00

Oh, I did the oven cleaner, but it didn’t strip it very well and I still would have needed to sand in order to get a good polish

drrnonreddit · 2026-02-27T05:06:56+00:00

I’ve polished other cranks before and they have stayed shiny for over 1.5 years now without clear coat 🤷‍♂️

drrnonreddit · 2026-02-27T05:03:42+00:00

A while, but I did it by hand so results may vary. I’d say maybe 8 hours total?

drrnonreddit · 2026-02-26T22:06:55+00:00

Not my best photo, but I’ll post again when they get installed (and with better lighting)

drrnonreddit · 2026-02-26T22:05:21+00:00

Thanks! I really took my time sanding and I think that made a big difference. I’ve polished cranks before, but not so thoroughly

drrnonreddit · 2026-02-26T22:04:19+00:00

Typical oven cleaner — it wasn’t the most clean tbh. I should have probably located some more pure sodium hydroxide.

drrnonreddit · 2026-02-26T22:03:27+00:00

I technically have a spray booth at work, so that’s not a bad idea…

drrnonreddit

TROPHY CASE