how to build a mountain bike for speed
March 10, 2014 11:24 PM Subscribe
i ride a trail in melbourne called westerfolds. it is a 5km switchy trail, short climbs, short descents.
I am riding a scott spark dual suspension carbon fibre, which is a beautiful bike.
but my feeling is that something tailored for the ride would be quicker again.
so i want to build something that will do the trick.
extra note, i love climbing so i guess focus is on getting weight down for the final product.
this is an exercise in what is possible, as well as i just want to get quick.
please give me any technical suggestions? mostly i just want a front suspension with light wheels, but is there any other trick?
my guesses include the following:
- remove the front derailluer and 2 chain wheels, and run with some sort of chain guide
- use mavic cross max wheels or fulcrum red
- 26er not 29er
- find the smallest clip pedals possible
- tubeless tyres
- source light seat post, seat, and bars
my guesses include the following:
- remove the front derailluer and 2 chain wheels, and run with some sort of chain guide
- use mavic cross max wheels or fulcrum red
- 26er not 29er
- find the smallest clip pedals possible
- tubeless tyres
- source light seat post, seat, and bars
On a 5 km ascent just moving to a hard tail will make a huge difference in terms of ease of climbing.
Depending on grade I would hesitate to run 1/10 vs a more standard 3/9 or 3/8 - you might miss those front gears on ascent and I don't notice huge weight difference test riding the different configurations. On 26 vs 29er - they ride so differently that you should make that decision based on style preference over weight. The 29er is much more stable and forgiving.
If you are looking for light then first choose appropriate frame and fork, then brakes, then tires, then the rest. Depending on budget and conditions you might consider disk only over entry hydraulics.
Don't over think it though. I ride a stock 26" Cannondale hard tail mountain bike, basically the cheapest one they had with basic features (lock out fork, disk brakes, under handle shifters, one step up from entry derailleur), I bought new for $700 on sale. First day on the mountain I was riding comfortably up hill while the dual suspension riders pushed their bikes. Front only might be enough weight change to make the difference.
My husband rides a 29er and his bike is lighter than mine - he stepped up in price on frame and fork.
Of course the cheapest way to drop weight from a bike is for you to lose weight, but you knew that.
Go to your local bike shop and test ride bikes at different price points with the different feature configurations. This will help you make decisions.
posted by crazycanuck at 5:15 AM on March 11, 2014
Depending on grade I would hesitate to run 1/10 vs a more standard 3/9 or 3/8 - you might miss those front gears on ascent and I don't notice huge weight difference test riding the different configurations. On 26 vs 29er - they ride so differently that you should make that decision based on style preference over weight. The 29er is much more stable and forgiving.
If you are looking for light then first choose appropriate frame and fork, then brakes, then tires, then the rest. Depending on budget and conditions you might consider disk only over entry hydraulics.
Don't over think it though. I ride a stock 26" Cannondale hard tail mountain bike, basically the cheapest one they had with basic features (lock out fork, disk brakes, under handle shifters, one step up from entry derailleur), I bought new for $700 on sale. First day on the mountain I was riding comfortably up hill while the dual suspension riders pushed their bikes. Front only might be enough weight change to make the difference.
My husband rides a 29er and his bike is lighter than mine - he stepped up in price on frame and fork.
Of course the cheapest way to drop weight from a bike is for you to lose weight, but you knew that.
Go to your local bike shop and test ride bikes at different price points with the different feature configurations. This will help you make decisions.
posted by crazycanuck at 5:15 AM on March 11, 2014
Hardtail all the way. Rear suspension eats power.
posted by Ironmouth at 6:05 AM on March 11, 2014 [2 favorites]
posted by Ironmouth at 6:05 AM on March 11, 2014 [2 favorites]
Best answer: Do you want to upgrade your current bike or build new?
- Don't put 26 wheels on a 29. Do get lighter wheels and run tubeless. We just built a set of Stan's Crest to DT Swiss 240S with triple butted spokes and that was a nice wheel. If you're not too heavy that's what I'd go with. If you are heavy, get the Arch instead of the Crest.
- Get lighter bars and a lighter seatpost.
- Switch to a 1x drivetrain. You'll lose a little chain, the front derailleur, front cable and housing, and front shifter. Don't use a chain guard, instead buy a front chainwheel made for a 1x system. RaceFace has been making some now that work great (alternating thin/wide teeth). Kinda like a po' man's version of XX1 or X01.
- Don't find the smallest clipless pedals. Find the pedals that work well for you, and buy the Ti version of those if they make them, or just the premium lighter version. If you're on something like M520s now and like those, switch to M980s. Same pedal feel, lighter weight, slightly nicer bearings. This is diminishing returns.
- Tubeless definitely. You should run tubeless even if you aren't concerned about the weight. There is no downside to running tubeless significant enough to not do it.
- Lighter saddle. Yes, this will drop weight. It's literally your ass though. Up to you.
- Since you're going to be shortening your chain anyway, you could just replace it with a hollowpin chain and drop a few more grams.
- Replace your housing with Nokons. It's a pain in the ass to set up but it looks really nice once you're done. It's slightly lighter than traditional housing.
- What brakes are you running? The 985 brakes are pretty freaking sweet and come in a few grams under the 988s. If you're already running 988 and don't use the extra adjustability features, consider switching to 985 (again, diminishing returns).
- I wouldn't do stupid stuff like run 160s instead of 180/203. You still want to stop when you want to stop. Not worth the weight savings.
- Fork. What travel do you have now and what fork is it? Is it an OEM RockShox or OEM Fox? Consider upgrading to something that's lighter but still has the travel you need. This will not be inexpensive.
- You can retrofit just about every M4, M5, and M6 on your bike with Ti replacements. You'll need anti-seize compound and a torque wrench.
posted by spikeleemajortomdickandharryconnickjrmints at 6:25 AM on March 11, 2014 [1 favorite]
- Don't put 26 wheels on a 29. Do get lighter wheels and run tubeless. We just built a set of Stan's Crest to DT Swiss 240S with triple butted spokes and that was a nice wheel. If you're not too heavy that's what I'd go with. If you are heavy, get the Arch instead of the Crest.
- Get lighter bars and a lighter seatpost.
- Switch to a 1x drivetrain. You'll lose a little chain, the front derailleur, front cable and housing, and front shifter. Don't use a chain guard, instead buy a front chainwheel made for a 1x system. RaceFace has been making some now that work great (alternating thin/wide teeth). Kinda like a po' man's version of XX1 or X01.
- Don't find the smallest clipless pedals. Find the pedals that work well for you, and buy the Ti version of those if they make them, or just the premium lighter version. If you're on something like M520s now and like those, switch to M980s. Same pedal feel, lighter weight, slightly nicer bearings. This is diminishing returns.
- Tubeless definitely. You should run tubeless even if you aren't concerned about the weight. There is no downside to running tubeless significant enough to not do it.
- Lighter saddle. Yes, this will drop weight. It's literally your ass though. Up to you.
- Since you're going to be shortening your chain anyway, you could just replace it with a hollowpin chain and drop a few more grams.
- Replace your housing with Nokons. It's a pain in the ass to set up but it looks really nice once you're done. It's slightly lighter than traditional housing.
- What brakes are you running? The 985 brakes are pretty freaking sweet and come in a few grams under the 988s. If you're already running 988 and don't use the extra adjustability features, consider switching to 985 (again, diminishing returns).
- I wouldn't do stupid stuff like run 160s instead of 180/203. You still want to stop when you want to stop. Not worth the weight savings.
- Fork. What travel do you have now and what fork is it? Is it an OEM RockShox or OEM Fox? Consider upgrading to something that's lighter but still has the travel you need. This will not be inexpensive.
- You can retrofit just about every M4, M5, and M6 on your bike with Ti replacements. You'll need anti-seize compound and a torque wrench.
posted by spikeleemajortomdickandharryconnickjrmints at 6:25 AM on March 11, 2014 [1 favorite]
As the world-beating Lance Armstrong said, its not about the bike!
But seriously, with all things there is a temptation (which I've succumbed to often) of losing sight of the activity and focussing on the equipment.
Unless you're competing at a high level, tweaks such as size of SPDs, tubeless/not, and weight of components on what is presumably already a high-spec bike is not going to make a huge difference. Fitness and skill are the biggest factors.
However, I conceed that there is a joy in getting your bike just right. Maybe see what others familiar with your trail recommend?
Also, Weight Weenies is a good resource for the lightweight fanatic.
posted by Kiwi at 1:25 PM on March 11, 2014
But seriously, with all things there is a temptation (which I've succumbed to often) of losing sight of the activity and focussing on the equipment.
Unless you're competing at a high level, tweaks such as size of SPDs, tubeless/not, and weight of components on what is presumably already a high-spec bike is not going to make a huge difference. Fitness and skill are the biggest factors.
However, I conceed that there is a joy in getting your bike just right. Maybe see what others familiar with your trail recommend?
Also, Weight Weenies is a good resource for the lightweight fanatic.
posted by Kiwi at 1:25 PM on March 11, 2014
Response by poster: spike good tips,
my project is now inspired.
i might start with a simple scott fronty,
and see where i can take it.
posted by edtut at 4:18 PM on March 12, 2014
my project is now inspired.
i might start with a simple scott fronty,
and see where i can take it.
posted by edtut at 4:18 PM on March 12, 2014
This thread is closed to new comments.
Some general advice:
Usually upgrading your wheels are the best bang for your buck, it can get quite expensive, what with the new carbon fiber offerings. Tubeless is very nice: cuts down on rotational weight and goathead problems, but it's best point is being able to run a much lower pressure, which could help with controlling the bike.
Dualies are usually seen as inferior for climbing than a rigid frame, but the better the FS bike, the less this is a concern - depends on how well your rear sus. is set up, and if it's got a lockout, etc. Dualies are also very nice to descend with, so who knows: you may lose a lot of time on your descent when trying to optimize your ascents!
posted by alex_skazat at 11:47 PM on March 10, 2014