Donohue 559 low-trail conversion

I'm slowly rebuilding the bike. Rattle canned over the grey primer patches, not pretty but I think it's an improvement. Mudguards mostly done. First time tubeless conversion almost worked. Front wheel appears to be good, but rear may not have sealed properly. No obvious leaks, but pressure drops considerably in an hour. Still need to order a smaller outer chainring.

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Didya hear about Compass new tyres??

I did, but 58mm would be extremely tight fit at best.

What fork is it you used on that? (too lazy to find the original thread)

It was built together with the rack by Piotr Lisiecki, see for example https://instagram.com/pilisiecki/ .

Bear in mind that the tyres are a lots thinner and doesn't have thread sticking out.

You were running 2.1 MTB tyres whose thread stick out like a sour thumb close enough to touch the stay, without the thread, I reckon there's ample room.

I can come up with other excuses, too. But seriously, having another option isn't a bad thing - though at those prices I'd need to be certain that the tyre would fit. I seem to recall that the carcass of the 2.1 racing ralph was only around 50mm, with not a huge amount of space directly to the sides. Anyway, I think tubeless Kojaks might be the next stop after I get fed up running knobbly tyres on road.

That's fair enough, I wax lyrical on riding high quality huge volume tyres on my 650b, hence the suggestion.

Compass also release the 650b in 48mm too, which would have been a better size for you had they come in 26".

Oops, thanks. I failed to realise this is the original thread, due to the title change. Ace bike, will be changing my old MTB back to a similar format soon.

Ah ok, I did wonder about the original thread bit. I though the amended version was more descriptive.

will be changing my old MTB back to a similar format soon

This one? Cool frame & builds, I remember seeing that before. I find it amusing that in a way I'm building a vintage MTB drop bar conversion look-alike out of a road bike.

Also, looks like the rear wheel/tyre sealed properly after all, so once I receive the 46t chainring I should be all set.

I'm pretty much done, finally. I did a short test ride, well chuffed. Simply fun to ride. The tyres feel surprisingly smooth even on paved roads, not in any hurry to change to anything else. I'm still gonna swap out the cheap bottle cages for King Cage Irises, these feel pretty flimsy.

One (or pretty much the single) annoyance was rattling from pebbles being thrown inside the steel mudguards when riding on gravel. I'm thinking of trying some "heli tape" inside the mudguards.

I used some wire to anchor the tip of the front mudguard, seems to work well.

Nice innovation.

This bike looks huge fun and very purposeful.

Yep that's it. I have everything now except some v brake noodles with adjusters, and some time to do it.

@edscoble are they the McClure's? I'm pretty sure the Halo's I'm using aren't worth their weight in shit.

Frikking love this bike. Donohue + 559 monsteur joy

This is inspiring. I like the chainstay surgery.
G.Berth. guards look great, did you add the flaps yrself?

Thanks for the kind comments. The progress has been frustratingly slow at times, but I'm very happy with how the bike turned out in the end.

@adrevporn Ha, surgery with a blunt instrument 😁. Yeah, I cut the mudflaps from 2mm rubber sheet. The material feels stiff enough not to flap about too much.

Looks great!

Yeah this is fantastic, it seems like you've done everything to make the bike exactly what you want

Or you could have bought a thorn ...

Sure, you can look at it like that, although I fail to see the resemblance to Thorn specifically. The geometry isn't really something you can readily find in OTP frames. I've thought of this a bit like an Elephant NFE on a budget, and now there's the Rawland Ravn that's available for pre-order.

Edit. ...unless #gotcha

I needed some extra space, mainly for a sleeping bag. I was meaning to use a tapered alpkit drybag, but attaching it turned out to be fiddly, and thigh rub was annoying. So I reverted to a regular drybag on rear rack. I hacked off bits from a cheap alu rack I had lying around, thinking that a) the original item was overkill for just a few kgs, and b) if this holds up in use, anything will.

Weight including bolts etc. ended up at 350g, so even with a drybag that shouldn't be too much more than a decent bikepacking saddle bag (for example the quoted weight for Revelate Viscacha is a little under 400g).

Couple of snaps from along the way:

Or you could have bought a thorn ...

Thorn don't do low trail geometry.

Lovely, well done!

Bits for new wheels with wider rims (24mm vs. 17mm internal width). With the current wheels I've found the rear in particular gets too squirmy when close to 2 bars, and I've had good experiences with similar tyre widths on wider rims.

The rims are Ambrosio AK30's, 600 grams a piece, so weight increase per rim is closer to 200g. Still, not a huge amount of choice for wide & rim brake, and these were among the lightest I could find. I did consider using single wall trial bike front rims, some of which are under 500g for 30mm+ width.

Weird surprise with one rim: all eyelets were missing. I would have though mfg QC or the shop should have spotted that.

I've been tempted to try the Compass Rat Trap Pass tyres, but I think with 55mm width rear clearances would be impractically tight.

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