Relationship - weight of bike vs. weight of rider?

[rsosborn]

I know this has been hit a few times. I'm looking to justify dropping weight on my bike. Many of have made different points on it. I'd like to throw another angle in. I'm sub-160lbs. Also, I'd like to throw a rule of thumb from motorcross into it and see what comes out.

It's been said the weight of the bike is not all-important. It can be a factor. My contention with a friend was that we are both sub-160lbs riders. Riding a sub-30lbs bike for us will be alot more noticable, than it would be for a rider of 230lbs.

People also always say "work on the engine". In motocross, the rule is that 5 lbs on the bike equals 2-3 horsepower on the engine. Given that each pound on our bikes is closer to our own body weight, dropping 1 lbs on the bike will make us that much faster, without any changes our "engines".

Fact? Fiction?

[tuba_transport]

It has been said a thousand times on every forum on the Internet(s), but it is still true.

Lightweight tires on lightweight wheels makes a world of difference. Rotational mass is where it is at much moreso than lighter frames. Lighter shoes, pedals, and cranks are the other sources of rotational mass.

[DaveG]

It has been said a thousand times on every forum on the Internet(s), but it is still true.

Lightweight tires on lightweight wheels makes a world of difference. Rotational mass is where it is at much moreso than lighter frames. Lighter shoes, pedals, and cranks are the other sources of rotational mass.

But it's not really true. Rotational mass makes a little more difference than weight on your frame, but rolling resistance makes MUCH more of a difference. I can go from a 700 gram tire that rolls well to a 600 gram tire w/ sticky rubber and I feel like I'm riding in tar.

Flip your bike over. Give the front wheel a tiny flick w/ a finger. Unless your disc brake is rubbing that wheel is going to spin for a while, all from a little finger flick. Now compare that to what your legs can put out.

Losing weight on a bike does help, but NOTHING helps as much as just getting stronger.

You can crunch the numbers on web sites like http://www.analyticcycling.com/ and it will show you that losing a couple of pounds doesn't make THAT much of a difference when going up hill.

Of course, if you lose those pounds by riding the heck out of your bike, you probably will be tons faster up hill, but it's not primarily because of the weight loss.

Dave

[CRAIG2]

Bike color is more important than weight. Buy a black, red, or blue bike if you really want to go faster. Buy an orange bike just to make those who own black, red, or blue bikes jealous. Ride a unicycle in an ice storm if you want to be like Pete. :p

[Jeep]

I think the biggest impact is on the agility and quickness of the bike. On a light bike the bunny hops are easier.

For maneuvers like pushing your bike forward to go over an obstacle, lifting the rear wheel etc... it makes a big difference.

I know I enjoy my rides a lot more on a light bike even though I don't necessarily go faster. (that's why I'm still riding a hardtail)

[DaveG]

Bike color is more important than weight. Buy a black, red, or blue bike if you really want to go faster. Buy an orange bike just to make those who own black, red, or blue bikes jealous. Ride a unicycle in an ice storm if you want to be like Pete. :p


Yellow bikes are CLEARLY the fastest.

[beerMe]

I'd rather lift beer bottles until they lighten up than a bike with my heavy assss which isn't getting any lighter from the beer.
Light bikes are easier to load onto the car...

[DaveG]

Bike color is more important than weight. Buy a black, red, or blue bike if you really want to go faster. Buy an orange bike just to make those who own black, red, or blue bikes jealous. Ride a unicycle in an ice storm if you want to be like Pete. :p


Yellow bikes are CLEARLY the fastest. The proof is that I own NO yellow bikes. It's definitely what's holding me back.

[Dirt]

The weight of your bicycle is directly related to the riders self esteem. ;)

[DaveG]

The weight of your bicycle is directly related to the riders self esteem. ;)

Perhaps. I'm going to go put my 23 pound FS bike in the back of my Hummer now if you don't mind.

[saxman]

I've found that dropping one pound on a bicycle can make a significant difference. My FS came off the bike shop floor at 32 pounds. With a new fork, wheels and tires, the weight is around 28 - 29 pounds, and it has made a huge difference.

Unfortunately, as my bike weight dropped, my body weight increased. When I first joined MORE, I was a lightweight around 135 pounds and could scoot up just about any hill on my 25 pound HT. Now I'm around 155 pounds, and I can definitely feel how much tougher it is to get those extra 20 pounds up hills...even on my road bike.

I figure once the weather gets warmer and I'm riding both longer and more often I'll be able to knock off around 5 - 10 pounds.

[eloach]

I know this has been hit a few times. I'm looking to justify dropping weight on my bike. Many of have made different points on it. I'd like to throw another angle in. I'm sub-160lbs. Also, I'd like to throw a rule of thumb from motorcross into it and see what comes out.

It's been said the weight of the bike is not all-important. It can be a factor. My contention with a friend was that we are both sub-160lbs riders. Riding a sub-30lbs bike for us will be alot more noticable, than it would be for a rider of 230lbs.

People also always say "work on the engine". In motocross, the rule is that 5 lbs on the bike equals 2-3 horsepower on the engine. Given that each pound on our bikes is closer to our own body weight, dropping 1 lbs on the bike will make us that much faster, without any changes our "engines".

Fact? Fiction?

Mmmm...... in this case, is there a benefit for "light headed"? ;)

My advice is to make the bike a pound lighter and your wallet $500-$1000 lighter and see what you think. Of course you will go faster... but, where are you going? Are you planning on making a living as a pro rider?

If you want a fast light weight bike with 5" of travel you can buy a Scott LTD that weighs ~20 pounds for $9000. Is it worth it? I think you should pick your price point and stay with it. You can get a pretty darn good 25-27 pound bike for ~$3000 these days.

Another BIG point here is MTB vs road. For me, I can make my Giant Reign (my heaviest bike) at 33 pounds go faster on most ST around here than I can keep it on the trail at. Now, yeah, I'd rather ride something else UPHILL, especially on a fire road (like a cross bike), but for an MTB race on single track... well you get my point. On an MTB it's really the SKILL of the rider in addition to the fitness that allows the rider to maintain high speed. On the road, I really feel it's more an issue of fitness, bike weight and aero. So for MTBing, I feel a skilled rider with a $2000 30 pound bike is going to beat the crap out of a not so skilled rider on a 20 pound bike.

Want to hammer the point home? Get Dan to ride WF or something easy with you that you might THINK you would hang with him on based on fitness and see how fast you're dropped. Then try the same thing on the road. It's all about the skillz... and I wish I had some!

[rciracing]

Tires and light weight tubes are easy and affordable ways to lose weight. Wheels are a more expensive approach. But when it comes to wheels, I think it is more important to go hand built by an experienced builder. Properly tensioned wheels are a tough sell to most folks until you ride them for the first time.