Self-Build: 21st Century RandoFixed

What are you up to these days? Are u still in the industry?

No, I'm just starting a grown up office job. Had to go shirt shopping last week which is a first for me (the Charles Tyrwhitt google trick. IFYKY)

Haha yes I’m familiar with this. New job/new shirts has always been a bit of a tradition for me too.
All the best for the new role

Bought an accurate set of scales today to keep an eye on the weight of this.
Frame and fork are coming in at 2.54 kg
I think most of that is the paragon sliders which are pretty porky. The lack of back-wheel-weight on a fixed should balance that out a bit

Enjoying this - commenting to follow

Can't wait to see more, this is one of those builds I can see future me going in for when the pre curse finally bites the dust. Great work so far!

A bit of tech help needed here....
I bought a Superstar EC44/40 & ZS44 mix and match headset to run a tapered carbon fork in my 44 mm headtube.
The ZS44 aspect of things looks to be self-explanatory but the lower race is a bit confusing.....
At risk of being an ignorant prick, does this fork steerer have an integrated crown race or is it just a proprietary, massive steerer that won't work with an EC44/40...?

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When I stick a crown race onto it, there's clearly a problem...

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But if I remove the crown race and just use the rubber seal such that the bearing makes direct contact with the carbon steerer it looks close enough to normal.

I feel like a right dunce with all this madness - before we even get onto measuring thread pitch and taper angle on the thru-axle holes at the other end of the fork!!!

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So the question is:
can I use this fork with the carbon steerer in direct contact with the lower bearing race??

Or do I need a different fork worth a smaller taper so I can fit the aluminium crown race that came with the EC44/40 headset???

I feel your pain on this as this happened to me and meant that my Salsa fork with an integrated crown was incompatible with a CK headset as the bearing angles or whatever were different.

What fork is that? It looks like an integrated race to me. You’ll need to look up the specs on the fork and the headset to see if they match. I had to contact the manufacturers as they weren’t readily available on their websites.

yep, i blundered into this with an ebay chinese fork and had a not-ok gap where the lower bearings sat wrong on the fork, i resold the fork in ignorance of how to fix it

Yeah it's an integrated race. Check the angle of it and check that the headset requires the same bearing seat angle and you should be good to go as long as it spins ok.

And yes, Chris Kings use a proprietary crown race and are not compatible with anything else.

Thanks everyone. That’s good to know.
The fork is from a BMC Road machine. I liked it cos it takes 32mm tyres and guards and has some neatly concealed mudguard mounts so it'll be good to get it to work...
According to the internet, the bearings on the Roadmachine are MR019 which have contact Angle: 36°×45°, Height: 7.5mm, and ID/OD: 40.0mm/51.8mm.
My Superstar headset comes with a bearing of contact Angle: 45°×45°, Height: 7.0mm, and ID/OD: 40.0mm/52.0mm

Clearly, the issue I have here is that the fork wants an internal chamfer of 36° and the bearing in my headset has 45°

Looks to me like I'm going to need this: ACB 6808 CC Headset Bearing 40x52x6.5 36x45°

and then keep the superstar crown race and lower bearing in case I ever change the fork for something else.
The only dimensional issue here is the height - the stack on this 36° bearing is a 0.5 mm lower so hopefully the cup won't bottom out on the fork crown with the headset is pre-loaded....

Ahh, the good old 36° or 45° headset bearing angle question. In my case it was (I think) a mix of FSA and Cane Creek that wouldn't work together. Bastard 'standards'.

And to think we used to find the existence of a JIS headset annoying.

I know right!!
I'm glad I've just got a BSA threaded BB but I'm expecting a similar level of complexity when it comes to thru axles

I don't really follow build threads, but when I do follow them they are the best build threads in the world. Very exciting and excellent work!

Thanks, this means a lot from one of the forums fixed-audax-heroes!!!

Just used a precision engineering technique to measure my steerer taper angle and confirm that it is indeed a 36deg taper so I’ve bought a replacement bearing for the superstar headset

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I fitted the superstar headset with the 45 deg. Angular contact bearing and then whacked a stem in there to see how much spacer to build into the new stem design.
My estimate is that the 36deg bearing will increase the amount of spacer by ~3mm judging by the gap between crown and lower cup

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With the proposed stern design I get 12cm of saddle to bar drop which should be good for fast but comfy riding

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Really really good.