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Discussion Starter · #1 ·
I am not riding the lightest bike in the world but I was just wondering how much it really matters. It isn't a pig by any means. I know i need lighter wheels, but what about the rest.

What weight overall on the bike should i be shooting for without breaking the bank?

Thanks,
 

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There are several factors to consider here... What type of bike? What style of riding? And what's your budget?

I'd love to help answer your questions, but tell me a little more about your riding style and bike first.

A good rule of thumb is that a bike is a little like a bottle of wine - The difference between a $3 bottle and $15 bottle is tremendous. However, only serious wine enthusiasts can actually appreciate the difference between, say, a $15 bottle and a $500 bottle.

I personally think many people get too hung up on weight, but it certainly does make a difference on the performance of the bike, and it really depends on rider preference.
 

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Discussion Starter · #4 ·
Component list:

Zion 4130 Frame
RockShox 100mm Reba
Race Face Dues X cranks
Race Face Dues Riser Bar and Stem
Thomson Seat post.
WTB Saddle Cant remember the version but it has Ti rails and carbon.
Crank Brothers Pedals
WTB SpeedDisc Wheels.
X-9 Rear Der.
X-7 Front
XO 11-34 Cassette
 

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Personally? I wouldn't touch it. Upgrading a couple components to shave a few grams will be hardly noticeable, and very expensive. You already have great parts on there. Like I said I personally feel too much emphasis is placed on weight alone. I say save your money and someday buy a new bike. Or, if anything, upgrade the fork for better performance. But for a hard tail, it sounds like you have a pretty good set-up.

Remember, heavier weight also means more momentum (downhill and on flat sections). I ride an all-mountain bike and specifically chose the aluminum frame over the carbon because I wanted a bit more weight.

Shaving grams can be like a crack addiction: Do it once, and from that point going forward you are never satisfied...
 

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mutaullyassuredsuffering
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Weight

SurfSailRide said:
Shaving grams can be like a crack addiction: Do it once, and from that point going forward you are never satisfied...
After a couple years of the obsession I went on a 12 step program and am backing off of weight weenie-dom. While not heavy, I'm putting heavier parts on my bike as time goes on. There is a point where you do sacrifice durability and add a bunch of time and risk.

Jeff, In regards to your bike, I wouldn't worry so much about weight. If your wheels aren't tubeless, I'd do that just for all of the other reasons. You can save some rotating weight there, but rolling resistance will have an even greater (and better effect).

As far as non-rotating... The classic formula says that each kilo can reduce pure climbing time by around 1.5% If you go nuts and take 1 lb off of your bike, then that nasty climb at snowmass will be 5 or 6 seconds shorter for you...Not really enough to make a difference, especially when you can make up for that 6 seconds in just giving a fuzz more effort to hang with another racer. Looking at your setup, you can save a few grams here and there, but it's not going to add up to much.
 

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Jam Econo
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That's a pretty decent build. Those Zion frames are supposed to actually be pretty light for chromoly.
If you can swing it, you might try and pick up a lighter wheelset (Speed Disc are 2000 grams). Without too much trouble you could reduce rotating mass by 300-400 grams.
I'll second going tubeless (if you haven't already); the reduction in rolling resistance, flat reduction, and increased traction are well worth the price of admission, or any hassle.
What do run for tires?
Kenda Karmas are light and sticky.
 

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Discussion Starter · #12 ·
CB2 said:
That's a pretty decent build. Those Zion frames are supposed to actually be pretty light for chromoly.
If you can swing it, you might try and pick up a lighter wheelset (Speed Disc are 2000 grams). Without too much trouble you could reduce rotating mass by 300-400 grams.
I'll second going tubeless (if you haven't already); the reduction in rolling resistance, flat reduction, and increased traction are well worth the price of admission, or any hassle.
What do run for tires?
Kenda Karmas are light and sticky.
I do run Karma's. i think that is going to be what i invest in this year. Wheels.
 

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There's weight and there's weight.

I spent some time reading the Weight Weenies Forum over a several week period. What I gleaned overall was that a light weigh bike was a matter of considering each and every piece of the bike as it was being built. With that perspective lightening up a bike from a current "heavy" disposition made little sense. The expense to manage a reduction in one area didn't yield much benefit.

My son raced a 31 lb. Rockhopper, finishing in the top handful for the season. He was bested by better riders. I just built him a sub 23 lb. HT. Most of the weight was in the frame, but 1.5 lbs in the shock, .5 lbs in the seat and seat post, .5 lbs in the crank/bb, nearly 2 lbs in tires/wheels.

I noticed how much lighter the whole bike seemed from the feet forward. The frame had been used with slicks as a road SS and it was always quick-steering but now seemed quicker. Not jittery mind you, just more responsive. I also felt I could flick the bike about more and maybe that is a good thing, who knows.

As far as faster? He weighs 135 and and 31 lb bike vs a 22 lb bike is a 5% weight savings. My guess is that it will make a difference. Now if you have a "heavy" bike how much are you going to have to spend to make it a lighter one? A lot, and you still have the basic frame weight. So my call is what I usually tell folks about UPGRADITIS; replace parts as they break with better parts. Bank money that burns a hole in your pocket. No really, put it in the bank. Meanwhile dream about your next bike.

And wheels/tires/tubes? Same answer.
 

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Berkeley Mike said:
I spent some time reading the Weight Weenies Forum over a several week period. What I gleaned overall was that a light weigh bike was a matter of considering each and every piece of the bike as it was being built. With that perspective lightening up a bike from a current "heavy" disposition made little sense. The expense to manage a reduction in one area didn't yield much benefit.

My son raced a 31 lb. Rockhopper, finishing in the top handful for the season. He was bested by better riders. I just built him a sub 23 lb. HT. Most of the weight was in the frame, but 1.5 lbs in the shock, .5 lbs in the seat and seat post, .5 lbs in the crank/bb, nearly 2 lbs in tires/wheels.

I noticed how much lighter the whole bike seemed from the feet forward. The frame had been used with slicks as a road SS and it was always quick-steering but now seemed quicker. Not jittery mind you, just more responsive. I also felt I could flick the bike about more and maybe that is a good thing, who knows.

As far as faster? He weighs 135 and and 31 lb bike vs a 22 lb bike is a 5% weight savings. My guess is that it will make a difference. Now if you have a "heavy" bike how much are you going to have to spend to make it a lighter one? A lot, and you still have the basic frame weight. So my call is what I usually tell folks about UPGRADITIS; replace parts as they break with better parts. Bank money that burns a hole in your pocket. No really, put it in the bank. Meanwhile dream about your next bike.

And wheels/tires/tubes? Same answer.
Well articulated. Great Advice.
 

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While climbing at a constant power output, weight reduction has a linear effect on your VAM (vertical rate of ascension in meters/hr).

In other words, weight reduction has a very real and measurable effect when you're going uphill. Technical ability aside, it changes your speed by altering your watts per kilogram ratio. Same watts, less kilograms = greater rate of ascension.

I weigh 64kg. My bike currently weighs 11.5kg. Shoes, socks, skinsuit, and helmet are another kilo. Half a kilo for a water bottle. Total system weight is 77kg.

Let's say I'm facing a climb that is 15min in length. It's a race, and I want to make that lead group heading into the downhill singletrack.

At 360w, that puts my total system watts per kilo at 4.67. If I drop 2kg from my bike, that puts me at 75kg, and 4.8w/kg. That's a difference of almost 3%. If you're doing a race in the mountains, most of your time will be spent going uphill. Let's say it's all up or downhill. Fireroad climb and technical singletrack descent (to make it as close to 50/50 as possible). Even then, you're probably descending 3x as fast as you can go uphill. Call it a 3:1 relationship. If your race is going to take 2hrs, that's 1hr 30min spent climbing. 3% off that is 2min 42s. That's real.

You can train till the cows come home, but if you're riding your brother's AM bike, you'll be miles behind people who have trained in the same manner.
 

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Ladies and gentlemen, this is what happens when you you mix nerdy physics with fun sports... I think I just lost all interest in biking!

I'm kidding of course; that was really an excellent explanation. And your points is duly noted.

However, the point that BerkeleyMike made holds very true - "The expense to manage a reduction in one area [doesn't] yield much benefit." As Duke of Kent points out, a significantly lighter bike will make a difference in very competitive situations, but for the majority of us who A) cannot afford a $4000 - $8500 rig and B) aren't training for competitions of exceedingly high caliber, it is wise not to get overly caught up in the "gram game."

I say stick to Mike's plan: Replace parts (as needed) with better, lighter parts, and bank the rest of your money. When you can afford it, if you're still seriously competitive and need an extra edge, buy a new carbon (or lighter) rig. All the light components in the world won't add up enough shaved grams to make a significant difference on a Chromoly frame, and since you like the frame, stick to what you've got (and go tubeless, of course).

(Duke of Kent, no hard feelings I hope - that really was a good explanation, I was just joking around). :thumbsup:
 

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SurfSailRide said:
(Duke of Kent, no hard feelings I hope - that really was a good explanation, I was just joking around). :thumbsup:
None taken.

And, I'm also a firm believer in the "replace it as it wears out" philosophy, actually. Aside from my new race wheels, a free Dura Ace 12-27 cassette, a different length/angle stem, and a proper saddle, my bike is completely stock.

The stock Shimano M532 crankset is just begging to be replaced, too. I'm surprised that pile of crap doesn't come with all of the rings riveted together.
 

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mutaullyassuredsuffering
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Well Said

You guys hit it on the head. When the time comes to build a new machine, carefully analyze which parts go on the bike and build a nice package together. Swapping out perfectly good parts to save a few grams doesn't make much sense. I'm a fan of always building a bike from the frameset with the components I like, rather than buying stock and wasting time and money swapping parts.
 

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Totally valid, but I would add in that you should do a cost per second gained analysis, which would then tell you if you think its worth it given your financial situation. If you spend $1000 to gain 2 minutes, that's $500/minute. If you have the cash (or the sponsor), rock on.....otherwise, it comes down to how important those 2 minutes are to you.

To some its money well spent, to others its not. Its all up to you.
 
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