Karate Monkey: an MTB experiment

I love the idea of the KM, a bike you can build up any which way. I bought this as a bit of the spur of the moment thing late last year, off someone I know (a bit).

It was a good price, and came with both flat bars & brakes and Salsa Woodchipper drops.

It was described as being in good condition, but with a loose front hub. Well, the last bit was true, as far as it went! Pretty much everything needed taking apart and servicing, the paint is ratty and worn through in places, etc etc etc. And what is it about the transfer of ownership of a bike that makes the BB and headset disintegrate?

I've enjoyed knocking about on it as a single-speed. Then I decided for a laugh I'd enter an event called The Crossing, which is a three-day race (in that each day is timed) across the UK this summer. I ride road and cross mostly, although I used to MTB a fair bit.

The objective is to build a reliable, low hassle & capable cross-country bike. Imagine if a CX bike had a fumble with a Monster Truck. That.

I'm collecting the parts at the moment. The central bits of the spec are an Alfine 8 speed hub, a Jtek bar-end shifter, and a RockShox 30 Gold TK fork.

The one oversight on the frame is that there are no cable bosses on the chainstay and DT, which feels like the natural routing for the shift cable.

Brazing some extra bosses on is the first step in the overhaul. After 10 minutes of controlled violence it now looks like this:

I'll try to get into the workshop to braze the additional cable bosses on this weekend, then it'll be off for powder coating. I don't want it grey, I quite fancy something brighter.

Makes no sense adding bosses when they're already drawn along the TT/Seatstay. Any particular reason?

I was going to do that initially, but there's a bit of a problem when you combine Alfine hub and the seat stay routing on the KM.

To get the chain line right you have to flip the sprocket (which is dished to allow for adjustment), pushing the chain line outwards. What that means is that the chain runs very close to the cable and the shifter stop. The slightly ghetto solution is to bend the problematic part of the hub attachment, but I don't like that.

I could just zip tie the cable run to the chain stay and DT, but as it's getting repainted it's an opportunity to do it neatly.

Ah, missed the Alfine part. Makes sense now.

Paint it orange.

Bright orange is always good.

Will you be removing the v-brake bosses as well?

Orange was definitely an option, the other colours under consideration are a shade of Violet, possibly metallic, and Snot Green.

The last one was suggested by the missus, who's normally the Spirit of Subtlety when it comes to colours.

The bosses are two-part jobs, and can actually be unscrewed from the frame. I may take them off, but I won't debraze the mounts they screw into.

What do you reckon you'll be using this bike for mostly? Other than the 3 day of course. I've been thinking about converting an old MTB and im wondering wether theyre decent as a runabout bike on road? probably

^ a friend of mine has a KM, the same size and year as this one converted to fixed and he has used it on TT courses

really cool setup, whats the frame size?

^ a friend of mine has a KM, the same size and year as this one converted to fixed and he has used it on TT courses

Cheers for that, also +1 for bright orange.

What do you reckon you'll be using this bike for mostly? Other than the 3 day of course. I've been thinking about converting an old MTB and im wondering wether theyre decent as a runabout bike on road? probably the wrong thread i know

Mostly I plan on using it for a bit of bikepacking and just general off-road meandering. This is the 2011 KM, so it's bossed for a rear rack.

MTBs can make good runabouts, the longer top tube means that you have to be careful if you start doing things like running drop bars as you'll be very stretched. Having said that, I find this bike with a stem 30mm shorter than I normally use plus the woodchipper bars is comfy.

Oh, and this is the 18" model, so a medium by most people's reckoning.

Managed to do the brazing this morning. Sanded off the powder coat with 80 grit, quick buff with 120 and then silver brazed the extra cable attachment points in place.

All ready for the powder coaters. Orange seems the popular choice.

Mostly I plan on using it for a bit of bikepacking and just general off-road meandering. This is the 2011 KM, so it's bossed for a rear rack.

MTBs can make good runabouts, the longer top tube means that you have to be careful if you start doing things like running drop bars as you'll be very stretched. Having said that, I find this bike with a stem 30mm shorter than I normally use plus the woodchipper bars is comfy.

Oh, and this is the 18" model, so a medium by most people's reckoning.

Thanks for the info. If that project ever happens i'll definitely keep the risers. Much prefer them for if i ever have to go off road on trips with the family etc..
Your project looks like its going to turn out awesome and good luck with 'The Crossing'

Cheers for that, also +1 for bright orange.

bright orange?

Very smart brazing, watching this with interest.

Bit of workshop envy on my part too!

bright orange?

Fluoro fadez innit?
Just joking, should have been just *orange.

Bright orange or yellow gets my vote.

Nice work, looking forward to seeing this built up!

I love my steamroller. Now I want a KM. Convince me I don't want one as I live in West London where there is no off road or mountains or beaches.

^everyone wants one, everyone needs one.

I love my steamroller. Now I want a KM. Convince me I don't want one as I live in West London where there is no off road or mountains or beaches.

Towpath.

It's gone for paint this morning. RAL 2009, Traffic Orange.

Hard to judge the shade online, but basically, it's this.

Anything happening with this? Been a while...