A 057

[0435235]

I always loved the idea of mountainbiking but never really got into it until a teacher offered to take a few guys out biking for the last few days before summer holidays last year. I loved it. From then I began taking my bike (a Trek Fuel 90 from 2004 or so) out more often. The only problem I had was that the frame is 15.5" and even though I'm only 173cm ~ 5ft8in it is too small. So the search for a bike began.

This chiner story begins with a BKXC video.
Someone rode quite well and got asked what his bike was. He said it was a "350$ chinese carbon frame from Alibaba". Since I wanted to get a new bike ... I WAS HOOKED

My parents and friends tried to convince me to just buy a bike, but since I finished school last month I was in desperate need of a project anyways. Also if the frame is only ~450€ shipped I could get a carbon frame with either the same or even better components than a name brand alu bike for the same money.
While doing research on frames and parts I found this forum and honestly, all the builds and answered questions were an amazing help. I read that Peter is a trustworthy guy and so I gave it a shot.
The 057 frame amazingly arrived in germany two days after I ordered it. The less amazing part was dealing with german customs ...

My build:

057 UD Matte BSA 17.5"
NECO headset
Rockshox Reba RL 2018 120mm
Mavic Crossride Quest Tubeless wheelset
Shimano XT Upgrade kit (Cassette, R.Derailleur, Chain, Shifter)
Shimano XT BB
Shimano SLX Cranks
Magura MT5 front w/ 160mm
Magura MT4 back w/160mm
Seatpost - cheap offer on Chainreactioncycles
Handlebars 720mm Easton Alloy riserbars
Truvativ Descendant 40mm stem
Nukeproof Grips
The saddle from my old bike
The pedals (flats) from my old bike (whoever put them on must have been a monster. At first it was impossible to remove them but after using aggressive rust remover to combat possible seizing and standing on the wrench they eventually came off)

Pics coming soon.

[0435235]

Please excuse my username, I just didn't want to bother with finding a name when I registered.

[adbl]

Good luck with the build, you'll love the bike! I've had mine for a year and a half and love it 

[0435235]

Thank you. I'm pretty excited

[0435235]

Is it normal that the seatpost in a 057 can only be inserted about 15cm deep? There seems to be a thick piece of material around the inside of the screws of the rear bottle cage mount.
Also: Would it be an issue if I cut my seatpost to slide around this plate inside the seattube?

[325racer]

Pretty sure mine stops at the bottle cage screws.  Best would probably be to just shorten the seaport.  Usually there's more issue with a post being to short and not having enough material in the frame.

[adbl]

Yes, that is normal. They are threaded inserts that are essentially glued into the frame so there will be a build up of material around the cage mounts. I would suggest not cutting a slot in the seatpost rather cut the whole stem to a length that clears the cage mounts for your appropriate length needed.

[0435235]

Thank you both. I guess I'll just shorten the seattube, as you recommended.

[RS VR6]

Instead of getting the MT5 and 4...why not just get the MT Trail Sport(non carbon version of the MT Trail). It comes with the dual piston of the MT5 and single of the MT4. Plus you get the new HC lever.

[0435235]

My decision was based on cost. MT Trail Sports are 185€ to 200€ with the main advantage over the MT5+MT4 being better levers. The MT5+MT4 combo was 129€ when I ordered it. It was more convenient to stay a little below my max. budget (my parents allowed me a budget of 1900€ of my own money) so I'd have a little spare money in case of a "bike building emergency".

[RS VR6]

Nothing wrong with that.

Oh...curious why you chose a dual piston caliper for the front. I have the MT Trail Sport on my trail bike and it has a lot of braking power. Seems like a lot of power for an XC bike.

[0435235]

Why wouldn't you?
What it comes down to is: You may not necessarily need all the braking power all the time, but there will (probably) be occasions on which you'll be sorry if you don't have it.

There is (almost) no worse feeling than having not enough braking power and realising you're up for some "not so fun" time. Maybe it's just too high speed on a new trail and a corner you misjudged. Or ... Last year I was almost run over on my way to a friend's house because a driver didn't pay much attention at an exit . I slammed my brakes but still touched the car and went down. If the brakes had been a little stronger I could've avoided the car by a few centimeters. Luckily just road rash, but still annoying.

Do you have any bad experience with too strong brakes?

[RS VR6]

A dual piston caliper seems like a lot of power on a 160mm rotor. I would imagine that it would build up a lot of heat on a smaller rotor if you were to do a long descent. Its typically used on bikes with larger rotors that are used for large descents with longer travel bikes. Just be careful when you grab that front brake hard for the first time. I'm using Shimano XT brakes on my 062 and it has more than enough power to throw me off the bike.

These are nothing more than my own thoughts. It's just not that common to see such a large caliper on a XC bike. If it's what you choose...then more power to you.

[gohloum]

A dual piston caliper seems like a lot of power on a 160mm rotor

I have to agree on this.  I think it could potentially create a more dangerous situation than safety.  I'm running Hope X2 single piston on the front and it will put me over my handlebars.  You are probably better off swapping out your front rotor for one with a little more surface area if you want more braking power.  I originally had a rotor that had more surface area like the Shimano Ice rotors.  It was just too much.  Too easy to lock up the wheel and not enough modulation.  I switched to a lighter XC design which has bigger holes and much less surface area.  Now I have very controlled braking with great modulation, but still enough to lock up the wheels.

[0435235]

Did a quick first ride today, time for some impressions:

- It's huge but steering is great.
- It feels extremely light (especially) on roads.
- The back end is quite bouncy on roots and small to medium stones.

Also to anyone on a strict budget without bike-building experience who might read this ... Stay a little below your budget, you never know which special tool you might be missing until you really need it. In my case it was a cable cutter. Let's just say it's a bad idea to try cutting shifter cable housing without one, let alone brake lines.
 
Parts:
Reba: The 120mm Reba comes without any tokens and feels very linear. It almost uses full travel when riding down stairs, so tokens will be added.
Cassette: 11-46 is most likely overkill for what I'm riding. The steepest climb here is a street with around 14% gradient and I didn't need the 46t cog to climb it.
Stem: 40mm is very short. It's nice if you love having a short stem for descending and snappy steering, but I see why many people (especially racers) choose to run long stems.
Tyres: Mavic Crossride Tubeless Quest don't feel great ... my back wheel lost grip in a regular turn without any braking going on.

Brakes:
I read your concerns and went at it slowly. A few things surprised me:
- The bitepoint on the MT4 and MT5 is very different from each other. The MT4 grabs earlier while the MT5 starts braking with the same force with the lever about a centimeter closer to the bar.
  (Is this normal or could there be air in the system?)
- The MT4 can brake quite strong.
- Maybe the brake pads are not broken in enough yet, but atm. they grab soft enough to provide smooth braking even from high speeds (I hope they don't become more grabby).
- The MT5 seems to be not much stronger than the MT4 (if at all). BUT it feels like it offers (way) wider modulation over the MT4.
All in all I really like them and honestly, my mechanical disc brakes felt way more dangerous because they didn't offer as much modulation which lead to easier lock-ups. I will probably follow your advice and get a 180mm rotor in the front in the future just in case I get to ride some long descents with hard braking.