I’d say that lighter is better, as it is with most unis. I either ride 150s without brake or 137s with a brake which I find perfect, it’s fast and out of control What size of wheel do you have? I ride 24"x3", 137mm cranks and a brake, I find this setup pretty much perfect except that my uni is really heavy.
I’d say lighter is better. I don’t see how more weight would help you. As far as stability, the weight isn’t keeping you balanced, your muscles are. And your muscles have to work harder to move more weight.
I suppose in theory a wheel that weighed nothing would not provide any gyroscopic forces. But I’m not sure how much those forces are really doing, and we don’t really have to worry about the nonexistent weightless wheel.
It makes sense to me that every gram of weight removed from your ride should save you energy, allowing you to ride longer, and increase the limits of what you can possibly do. But if losing a gram off your uni only allows you to add 1 mm to a 10km ride, is it worth the cost and effort? How much distance/effort does each gram save you? Maybe some other variables could have been tweaked to get the same increased performance: endurance training, improving technique, nutrition, a bowel movement :p, etc.
Short cranks offer your legs less leverage to climb hills, and likewise, to keep yourself from rolling downhill.
I’d get longer cranks. I think 150’s are arguably the all-around size for multi-purpose muni. So I’d consider greater than 150’s if I was focusing on extreme downhill.
Without a brake, your legs do all the braking. A brake can take a lot of this work away from your legs. And it may give you finer braking control than your legs can.
The need for a brake also relates to your crank length.
The shorter your cranks, the less leverage your legs have, the more force they’ll need to provide, the more fatigued they’ll get, the more a brake becomes helpful.
I define an extreme downhill as one that will seriously injure you if you fall and can’t stop from sliding/tumbling. Even if only 1 out of 100 hills you ride are extreme, you don’t want to lose control on that one hill, because it only takes one to take you out.
So I’d get a brake if I were going to ride any extreme downhill.
@ Jaco Flans:OK i have a 24x3 KH07-10 and I ride only DH (no uphill or XC) with it!
@ everybody: So you say lighter is better :d
and a brake is necessary if you ride all hills, so i go buy one
but what about the cranks are 137mm with a brake still OK enough for all hills? or should i go longer and what size than 140/145/150/160/165 or even longer?
If I was you, I’d stay with the 137s and get a brake since you only do DH. The brake really helps in DH, but it’s also possible with 150s and no brake (it’s really hard on the legs though). You can also try longer cranks, some riders like longer cranks, I like shorter cranks because it gives more speed
The reason you don’t ride uphill is probably because you can’t do much climbing with such short cranks
Seriously, 137’s are for a trials uni, not muni.
Get some longer cranks, they’ll give you more power and control, in a sense making you stronger in a way that makes the muni “seem” less heavy.
If you are not doing huge drops, I suggest dumping the heavy KH Moments cranks and picking ups some lightweight QuAx cranks in a 150mm. If you are doing drops, then a light and strongish crank is the Nimbus Venture 150mm.
If you really wanna climb like the wind, try some Koxx K1 160’s That’s what my son rides and he knows how to climb! These are about as long as should go on a 24, otherwise you’ll start having a lot of pedal strike (on rocks, roots, etc…)
I’d hold off on the brake, longer cranks will increase your braking and you may find that you don’t/need want a brake. Also, dropping weight with cranks while adding a brake, this is not the way to lose weight
You already have a light muni, KH is about as light as you can get. A Ti hub would shave some weight, but they’re fragile. Get some nylon pedals like the Odyssey Twisted PC, loss a few ounces that way. Try cutting your seat post down. Adding a carbon fiber seat base would shave a few ounces. Of course your biggest weight penalty is that 3" tire, but then DH does work best with a fat tire
If you think you can climb fine with 137’s, then by all means, though I’m thinking you must have much flatter hills than where I live
So if it’s just weight you wanna lose, then dump those Moments cuz they’re heavy, go with my other suggestions.
For sure consider a lighter tire, esp if you’re downhill is a speedy one, which suggests a trail with fewer significant obstacles and drops. You can probably run a narrower MTB tire and save 800-1000gms!
A brake might be worthwhile, but only to slow you down because you can’t slow yourself with those short cranks.
As a sidenote, I am always curious to see what Kris likes to ride, though knowing his skills, he is obviously going to steer toward gear that is less suitable to “normal” riders, of which I am one
I ride a Larry 3.8 on a Surly, run a brake and push 170mm cranks. There is no way I can do what I do on 137’s, dang, I upgraded from 165’s and a Duro 3" just to do what I do