Author Topic: MTB conversion to Disc Road bike  (Read 4271 times)

SportingGoods

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MTB conversion to Disc Road bike
« on: July 06, 2016, 03:17:46 AM »
Hi everyone!
This is more a teaser then anything else for now :)

I'm going to upgrade my current MTB soon to Full Suspension. I used to temporarily convert this 29" hardtail into a road bike in the winter (going down to sub-8kg). I was swapping fork (26" MTB carbon rigid fork), wheels (ZTR Crest equipped with Durano 28mm), dropper post (Carbon post) and doing a bit of change in the chain ring.
That was too much work!

So I have decided to permanently convert this hardtail into a disc road bike. I plan to do it properly  8). I have already decided that I'll order:
- a carbon dropbar (B6 from Peter), for a real road bike look!
- Tubular rims, (RM30T-23 from Carbon Speed as well). My wheel sub-plan is the following:
    * take the very light Novatec D711/D712 regular hubs from my current MTB wheelset (converting those to Boost hubs)
    * Add the super light tubular rims
    * Use superlight DT Swiss Aerolight spokes
The wheelset will end up under 1.3kg, which is nice for carbon rims. If you add the gain of tubular vs. tire+tube, I loose over 700g in the wheels compared to my current road setup. That's MASSIVE difference at the most critical place.

I've not placed any order yet but I'll keep this post updated with thoughts and decisions :)

As I'll be transferring most of the equipment to the full-sus frame I will also need to buy:
Drivetrain + brake: unsure if I go with cable or hydraulic brakes. It will be a real road group for sure. Mechanical disc would allow to buy a complete group, which is usually cheaper then buying separate. I would just have to add the mechanical calipers.

EDIT: After looking into some other posts related to disc road bike I think I will go mechanic disc brake instead of hydraulic. The reason is that hydraulic now uses a different mount system (flat mount). I plan on selecting Ultegra drivetrain (Dura-Ace is over what I want to spend). After looking at the weight of these components, I'm heading to a bike below 7.1kg (w/o pedals) for a cost around €1000.00 (parts to buy only, not including parts that are my MTB for now).
It's probably as good as I need!!
« Last Edit: July 12, 2016, 02:22:06 AM by SportingGoods »



carbonazza

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Re: MTB conversion to Disk Road bike
« Reply #1 on: July 06, 2016, 04:23:25 PM »
I'm very interested to see how it goes :)

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #2 on: July 13, 2016, 08:42:09 AM »
I just got a "bike fever"  8) I have started to acquire parts for this road disc bike.

And talking about disc, I have finally selected the disc brake. No! better then that, I have selected the best disc brakes. I decided to not go with hydaulic brakes for multiple reasons (high cost, weight, flat mount). I was about to buy Spyre calipers, the best mechanical one, but ultimately ran into this beauty:




http://www.edgesportsuk.com/store/juin-tech-r1-hydraulic-cable-pull-disc-brake-set-cyclocross.html
They are now my precious and should be with me in the next 2 weeks. Those are cable actuated hydro calipers. They offer both the power and modulation of hydro with the simplicity of cable shifters. They are very light too, 142g/caliper. Not too expensive either.

I have also found a good deal on an Ultegra 6800 11sp Group. 579€. And I will resell the rim brake (probably 80€). I have selected a compact 50/34 crankset with a 11-28 cassette (my main usage will be riding mountains - I'm 40 km from the famous Alpes d'Huez, and right at the foot of another very difficult mountain).
So, I will end up with a high level disc group for about 680€. Not too bad (Ultegra shifter/hydro brake is 600€ the pair, just the shifter and calipers, not the complete group!).

Oh, and I have also ordered my tubulars. They should look beautiful with a red accent. Vittoria corsa evo CX III. 80€ the pair.



http://www.alltricks.fr/F-11936-pneus/P-83456-vittoria_boyau_corsa_evo_cx_iii_700x23_noir_rouge

Still waiting on feedback from Peter to proceed with my order for the rims and dropbar.
« Last Edit: July 13, 2016, 10:35:35 AM by SportingGoods »

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #3 on: July 18, 2016, 06:03:49 AM »
Hi guys!

Earlier then I thought, parts start to come in. I've received my brake calipers from UK today. They are just as described:
- Comes with all you need. 2x adapters (I don't need it, my fork/frame are already set for 160 mm), long and short bolts, 2x 160 mm discs (119g each), bolts for discs.
- Calipers weight 143g each.



Mounted on my rigid carbon fork, so far so good!



And I have processed my order to CarbonSpeed for a B6 dropbar and 30 mm deep tubular rims (all-around rims, not too small, not too heavy). Peter is really nice, he understood what I was doing so asked me if I want the basalt brake surface. I confirmed I don't need any. You would not expect such a high level of service from many people.

carbonazza

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Re: MTB conversion to Disc Road bike
« Reply #4 on: July 18, 2016, 03:21:23 PM »
I never thought cable disc brake could be any good.
I just replaced them on a kid's Trek by some cheap Shimano hydro, and my kid is very happy of the effortless braking.

You say cost and weight, but another advantage could be to have much more compatible cable brake levers/shifters available.

I'm curious about their modularity and how they perform in your roads.
A friend just came back from the Alps, and told me he spent most of his descending time braking to stay below a safe 60km/h
Great brakes seem vital there :)

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #5 on: July 19, 2016, 02:16:46 AM »
My first disc brake were Hayes mechanical. Not good! Only one piston (so either the disc rubs against the fixed one or is bent when braking). Not much power nor modulation. Really not good.
As you mention, my first motivation to go with cable is that it's a lot more standard (I could buy high-end levers for a very decent cost - Ultegra ; the mount is similar to MTB calipers - when hydro road calipers have a strange flat mount).

Then, these hydro/cable calipers have a very good review
http://www.bikeradar.com/road/gear/category/components/brake-calipers/product/review-juin-tech-r1-brakes-50248/

Unfortunately I won't be able to provide any feedback before September. I'll be traveling to Missouri next week and will be on vacation most of August. But I should be more then fine as I will be using them with 160 mm rotors (the standard for my frame and fork, no adapter needed) when road standard is 140 mm.
« Last Edit: July 19, 2016, 02:51:16 AM by SportingGoods »

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #6 on: July 19, 2016, 12:57:48 PM »
Another big delivery today! Actually 2.

Ultegra group is now at home. The good thing is that it is awesome, so nice looking and light. Some components are even lighter then planned (like an 87g front derailleur  :o). See some pictures of me weighting each component (I don't post all pictures :) ).

50/34 compact crankset

11/28 cassette

Beautiful levers (weighted with shifting cables)


The sad thing is that I had missed one obvious part in my component listing. The brake cables/housing were not included in any weight recorded. They were part of the Ultegra group though... and they weight a lot. About 180g. I'm now heading to 7.2 kg total bike (w/o pedals). Still not bad!

The second box was my tubs. 520g the pair, 20g heavier then announced, still pretty light and nice looking.



PS I also had a SRAM GX 11 speed shifter in this box that I am returning to the shop as I have ordered my Eagle group for my MTB.

carbonazza

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Re: MTB conversion to Disc Road bike
« Reply #7 on: July 19, 2016, 06:25:10 PM »
11/28 cassette
That is quite brave, to ride in the Alps.

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #8 on: July 20, 2016, 03:21:52 AM »
Well, not really brave. I took a long time to think about it and discuss with friends, read forum. The conclusion is that almost no one uses both a compact chainring (50/34) and a long range cassette 11/32 for the Alps. Here is what people do (as I understand):
- Most people don't use a compact, because they don't live in the mountain and don't need it.
- Most people who do have a compact use it with a very short range cassette. This way they benefit from a well staged cassette but don't have to push too hard on the hills (with 34 chainring)
- People who visit the Alps change either their cassette (for a 11-32), or the chainring (not always as low as 34). Not both.

So, as I live in the Alps I thought I had to go with a compact (I'll use the 34 very often), but 11-32 cassette would be an overkill (in France we call it "ceinture-bretelle" :D that's wearing both a belt and suspenders :) ). But I will only know if it was the right decision after my first climb!
And it's an important decision because the RD that comes with the 11-32 cassette group is a medium cage when the one of the 11-28 group comes in short cage.

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #9 on: August 03, 2016, 08:33:55 AM »
The last delivery before my vacation! The rest (frame, dropbar) will be at the end of August.
So, this came from Smud-Carbon. Very nice looking parts. Not cheap, but still a very good cost/quality ratio.

Saddle is just amazing. Nice looking (custom painted) and crazy light.


Then, 2 parts for a full 3K/Glossy finish. The braze-on clamp (my frame is a MTB frame, not equipped) will look like it's part of the frame. The top-cap with a red bolt to match the design of the bike.



Just 2 comments about Smud-Carbon. No rush order! It takes weeks to order, get the parts made and shipped. And I was surprised to see the parts come into a bubblewrap envelop. This looks risky to me, but no damage with my parts. I just wonder what would have happen if the saddle had been damaged. Problems for sure...

carbonazza

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Re: MTB conversion to Disc Road bike
« Reply #10 on: August 03, 2016, 01:26:54 PM »
Smud makes really nice parts. But as you said, communication is quite hard(I tried for a longer seatpost), maybe they are overwhelmed by demands.
72g for a saddle... wow, that is very light



SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #11 on: August 30, 2016, 09:35:49 AM »
I have received 2 boxes from Peter. One was my MTB Frame and hubs, but I also got some interesting things for my road bike...

B6 Bar. 190g. Really well made, with grippy section for the stem and levers, with a nice aero profile and routing for cables under the bar. Size is 42 cm. I already love it!!


Rims. 303g each. 30 mm deep, for tubular. I will fit those on my Novatec hubs currently on the MTB. I plan on DT aerolight spokes. See how nice the surface is, w/o brake surface.



My plan for the wheels is to start with my MTB 29" ZTR, currently mounted with Durano 28 mm. This way I will still have one pair of wheels while I'll be building 4 wheels (these tubular and my boost MTB wheels)...  :o
I will keep those for "gravel" type of rides. I'll use the Carbon tubular for real road ride (mountain).

SportingGoods

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Re: MTB conversion to Disc Road bike
« Reply #12 on: September 05, 2016, 03:43:30 AM »
Progress Update:

I have just been enrolled (by a friend) into a 120 km road race! September 25th  :o Better hurry!!
So I have started to put the bike together (before I get into the MTB):


Big bummer, I never realized that road bike crank axle are a lot shorter then MTB... Ultegra cranks are already on "Leboncoin" (the french Craigslist).

The plan now is to keep my XT cranks on the road bike and just buy chainrings (middle 34 and outer 48 teeth).  I'll first run a test with 32-44 chainrings, then I'll buy the 34 and 48! With that... I'll have to buy a crankset for the MTB :)

As you see, those are my 29" wheels. No time yet to put together the carbon Tubular wheels.

EDITS: I forgot 2 important points for those who plan to do something similar (MTB frame used as road bike):
- Road Front derailleur are bottom pull. Most MTB frames are top pull. Won't work. My Ultegra FD is on "Leboncoin" as well... I use my MTB FD, that was going to be useless on the 1x MTB anyway.
- Hubs  >:(. I've spent quite some time this week end to modify my free wheel (I'll have to do it again on the tubular wheels). MTB free wheel are all cross-compatible unless you use SRAM Xd driver, that's 9-10-11 speed. It's not true for road driver. 11 speed is wider then 9-10 speed. As there is no 11sp driver compatible with my hub I pulled out the file, and filed away 1.5 mm of each spline. I worked out a setup with my power tools, but it didn't work well, not precise enough. The file  (the right one) is all you need, easy enough to remain straight and remove the same quantity of each spline.
« Last Edit: September 05, 2016, 09:04:12 AM by SportingGoods »

Sitar_Ned

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Re: MTB conversion to Disc Road bike
« Reply #13 on: September 05, 2016, 12:31:31 PM »
I've been considering doing something similar with my 057 if I ever decide to get a 29+ frame. I'm still just not sure about the drop bars though. I had a road bike for a couple of months that I ended up selling because the positioning was just too aggressive for me and I contributed/associated that with the drop bars but knowing more about bikes now, it was in large part simply due to the very aggressive geometry of the road bike, in general.. I've been thinking that maybe drop bars fitted to my 057 would be a bit more of a relaxed road cruiser type bike rather than an ass in the air road bike like the one I sold. Hmm.

 Definitely sucks about the Ultegra cranks! Would've been nice to get them on. Maybe just getting some nice road rims and tires for my 057 would be the best route.

Interesting thread, thanks for sharing. Interested to hear your thoughts on how it rides.

carbonazza

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Re: MTB conversion to Disc Road bike
« Reply #14 on: September 05, 2016, 01:52:45 PM »
The file  (the right one) is all you need, easy enough to remain straight and remove the same quantity of each spline.
Wow... that is a very brave, no fear, activity!