How to Lighten my bike?

[Goodbadugly]

Get another scale or set it at -1kg before weighing the bike. That way it will weigh 8kg. Or even better. Set it at -2kg. 

[GoLefty!!]

Kieran,

 

get your EA right from your EC

 

EA = Well priced value

EC = Over priced carbon bling bling

 

[GoLefty!!]

PS JAmes,

 

heres a tip, even though you can feel the extra rotational weight of wheels, it actually makes feck all difference to your time around a course.

 

Yes I did the experiment.

 

also, even a difference of 1 kg on the bike, makes feck all difference to your time around a course.

 

Most road bikes are as light as they nee to be to be competitive on for 99% of riders in the world.

 

 

[javadude]

But a light bike does help when after a really hard training session you have to hang it back up on the bike rack in the garage. I've got an old steel frame and jeepers creepers is my back taking strain.

[Gasping]

Get another scale or set it at -1kg before weighing the bike. That way it will weigh 8kg. Or even better. Set it at -2kg. 

 

 

Great advice - especially for those of us that are budget conscious!

 

 

But a light bike does help when after a really hard training session you have to hang it back up on the bike rack in the garage. I've got an old steel frame and jeepers creepers is my back taking strain.

 

Best reason to go lighter. Dunno how this will tie in with the best advice given by Goodbadugly. I need something in between.

 

[Sterad]

Flit letica wheels, around 1300 grams, about R3500 on the net. what do you weigh though?

 

gp4000 tyres and lightweight tubes.

[bikemonster]

Going back to the wheels thing...I did some googling yesterday evening, but didn't find anything that would change my mind. So, this morning, while riding my bike, I came up with a thought experiment. Get comfy...

 

 

 

Let's put a cyclist on a set of rollers. That way there is no straight line acceleration at play, only the rotational acceleration of the wheels (and cranks and the rest of the drivetrain). Now, let's give the bike super-heavy wheels. It's only a thought experiment, so we can make the wheels as heavy as we like. Let's say 500kg each. Now, we ask the cyclist to pedal up to an indicated 30km/h on his bike computer. Remember, he's on rollers, so the bike itself is not accelerating. Basically we're asking the guy to spin up two heavy flywheels. It'll take a while.

 

 

 

Now part 2 of the experiment. Replace the super-heavy wheels with super-light wheels. Let's give these wheels a weight of 500 grams each. Does anybody seriously think that the 500 gram wheels will take as long to spin up as the 500kg wheels?

 

 

 

Now let's return to what passes for reality in your postcode. When a cyclist accelerates - and lightweight anything is only valuable for acceleration - he has to accelerate the whole package of bike plus rider from a lower speed to a higher speed. But he also has to spin up the wheels, and that is where the flywheel effect comes in. Of course in the real world, we do not go from 500kg wheels to 500g wheels but the effect is nevertheless real. Whether it will make a difference to your life depends on whether you are saving 500 grams, 50 grams or 5 grams.

 

 

 

We can debate the size of the flywheel effect, and I agree that over a course (hi GoLefty!!) it will make feck all difference, but for acceleration it will make a difference. Remember this thread is about making a bike lighter, and again, over a course, the ability to ride cleverly, taking advantage of other peoples' draft and so on is way more important than scraping 200g off your bike here and there.

 

 

 

For a very long time I was deeply sceptical of this whole notion (rotational inertia). Then I happened to change tyres from some heavy-ass sh!t that I'd bought solely because it matched the colour of my bike to Conti GP's. Suddenly climbing (a special case of acceleration) and acceleration were very different. Yes, I know, sample size of one and anecdotal evidence.

 

 

 

Finally, and I promise it is finally, somebody suggested changing the saddle. Change a saddle to get comfortable. Change a saddle to save weight and long rides could start to feel like a traditional prison welcome.

[Ha Ha Kieran]

Not so true BM... I had a San Marco saddle on my bike when I got it and changed to a SLR saving me around 150g model to model but my comfort level has increased. I agree with you though its not a cast in stone option, but is one none-the-less

[GoLefty!!]

bikemonster,

 

in your experiment you will only have proved that super heavy wheels take long to accelerate.

 

In the real world where the difference between a heavy wheel and light wheel is around 300gr, it will make feck all difference to the riders performance.

 

fit a super light XC wheel and replace with a DH wheel and you will see differences.

But for road bike wheels, the differences are really very small even though the marketers will tell you otherwise.

 

Johan's point is not that there is a difference, but the delta from one wheel to another is so small,it is not a real consideration when purchasing wheels,especially at the expense of strength.

 

Aerodynamics of wheels is my pet marketing dislike since most proven test data is gathered in a wind tunnel under ideal conditions. In the real world the  only really aero wheels are wheels that do not have a rider and bike frame anywhere near them.

 

So buy the wheels because they look nice and be done with it. its the same vanity that finds a market for aftermarket rims and tyres of Honda Civics.

 

[Eldron]

I can't understand the weight weenie issue. Money and bling over common sense.....

 

The bike weighs 9kg and the rider weighs 80kg - thats a total of 89kg.

 

To save 1kg will cost a wad of cash.

1kg of the total is only 1.12%...

 

Added to that the fact that lower weight only helps you on the uphills (and actually aids you on the downhills). So say in a race you climb 33% of the time (the other 66% we'll say are downhills and flats.

 

A whack load of money to save you 1.12% on one third of the race (and slowing you down on one third). Hardly sounds like a lot does it?

 

If your bike weighed >12kg I'd say you might even notive the difference. 1%? I think not.

 

Don't waste the money...

 

 

[Marius]

I agree, I use to believe my Easton Tempest II 1200g Carbon deep sections tubbies was so fast, a year later I've switched to my American Classics 420

s with PowerTap SL hub coming in at 1750g - I actually feel faster on the Classics. So save you money/

 

[Eldron]

I agree' date=' I use to believe my Easton Tempest II 1200g Carbon deep sections tubbies was so fast, a year later I've switched to my American Classics 420
s with PowerTap SL hub coming in at 1750g - I actually feel faster on the Classics. So save you money/
[/quote']

 

Ahhh carbon wheels are my other favourite bug bear....

 

Unless you're buying a carbon tubby wheel there is a good chance that they're more expensive AND heavier than a mid range alu wheel.

 

The reason is that unless you buy some top end carbon stuff the rim will still be alu - all you're really buying is a normal alu wheel with a carbon aerofoil.

 

If you're buying it as bling and don't mind the extra weight and huge price then good for you but chances are you're paying loads of cash for a heavier wheel.

[gummibear]

Go to gym and do some leg presses.will make you stronger and save you money.

[AndreZA]

Eldron, what about spending R400 plus on a carbon bottle cage just to save 10gr.

[GoLefty!!]

I am actually looking a precuring a slightly heavier bike because;

 

- it is more comfortable (ti)

- it is more crash worthy (ti vs carbon)

- it costs less to insure!

 

weight difference = 300gr which is nothing compared to the total weight of rider, water bottles, spare tube, bombs combined.

 

[NotSoBigBen]

Eldron' date=' what about spending R400 plus on a carbon bottle cage just to save 10gr.[/quote']

 

I go back to my point 'wear just one sock' 400 ZA Ronds saved ....