Current Projects chat and miscellany

Finished the sweet fixie.
I found out it was 1 of 80 frames made for a cycling club and used as rental bikes, this one is from 2008.
The frame doesn't have much 'chainring clearance' and the 46t ring was nearly toughing the chainstay. I use a Shimano ht2 BB on this and solved this by using a MTB BB of which the cups are 1mm narrower and using one spacer on the ds.

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Absolute class.

That's crazy-small chainring clearance for a track frame.

crazy-small chainring clearance for a track frame.

S300 Courier cranks have a narrow (40.5mm) chainline. Omniums are 42.5, which would solve the chainring clearance but the spider would crash the chainstay because Omniums.

Swapping to a normal road crank using the outer ring opens up loads of room. Obviously you then have to fuck with the sprocket chainline too, but it's worth it.

Ah cheers, yeah I like it too non-integrated. Considering routing cables through stem but then I need to sort a dcr handlebar as I don't fancy drilling my superleggeras!

Almost done 😅

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Rohloff and Bafang mid drive, you kept that quite... ;)

its combining all the best bits that where not being used in any other project. Still need to install and modify Aliexpressish frame bag, swap the front rotor for a 180 and a different (smaller) battery. Didn't hook up the speedbox yet as i need to rework the cable runs but i hand shifted it to 7 and rode it around the neighbourhood. 42x16 seems to be about right for it.

This needs a few air horns on the bars and mirrors:)

Exactly, has an obnoxious bell already. Im trying to fit in with all the old Austrian/German men touring. MAy need to swap the pedals to be more Birkenstock compatible.

Are Omniums worse for clearance than any other standard 144bcd track chainsets? I've only used them on modern frames.

Are Omniums worse for clearance than any other standard 144bcd track chainsets?

Yes, the spider is very thick at the bolt holes compared with other track cranks.

Thanks. Looks like I'm with Bauke Mollema again.

What Tester said. I had a set of Omniums for years and had to replace them because the spider didn't clear the chainstay on my Day One.

My Trek Multitrack hasn't seen much use lately.
Decided to move the Pelago Rasket from another bike, and I hope it will see some commuting use in this configuration!

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That's a lovely bike.

So after riding this thing it is now clear the fork is way too short. Handles bad at lowspeed espescially. So time time find a suspension fork. Needs an extra 50mm or so based on spec so mullet 27,5 up front wont do it.

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You can get this one from Soma at a few different AC lengths

Or a Salsa cromoto or Surly ecr fork

Yeahhhh i know. Problem is that this is supposed to be a "budget build" + stuff i had around. Fork would cost more then I have in "new" money invested in this build. I gues i could grabe something like this

I'm sure there are reasons so can someone with a better (better than non existent) understanding of engineering explain why you can't run spacers under a headtube in the same way that you can above it?

Well, you kind of can. Isaac used one mould for a track/TT frame and just stuck a spacer between the fork crown and the lower headset bearing to fix the difference in BB drop they thought necessary.

In practice, your main problem is that the steerer has a short oversized section at the bottom to fit the crown race, or with some carbon forks the bearing seat is moulded in place. Those are not insurmountable issues, but need custom parts made to interference fit tolerance levels, not just the generous clearance fit you have with normal spacers.

If you go more than a few mm, you have to start thinking about whether the steerer is really fit to take such cantilevered loads.

In the end, why would you even try? Forks can be readily obtained in a wide variety of axle to crown lengths, and if you want something that's not available off the shelf, they can be made by a frame builder.

Cheers!

Still not convinced Im a drop bar guy, tried a few builds but always find it a bit "meh".. Will give it a go as this is my best try so far.
Probably to add mudguards for the winter months as well, means finding a bit narrower tires as these 47mm (true 45) pushing the limits.. :)

Thanks for the answer, interesting!

It was all a long time ago so the pix are a bit tiny, but you should be able to make out the "standard" configuration with a low BB and the "track" configuration with offset track ends and fork crown spacer to give a higher BB

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It definitely looks a bit odd doesn't it?