[Closed] Weight & physics

Probably- a light bike and heavy rider means the bike can 'move more' under you....
A heavy bike will require more energy to manoeuvre, I would say.

DrP

how ever if your riding any sort of distance you want to keep crap off your back and thus the bike is the best place for it.

never understood the facination with camelbacks - most folk here could do their rides off one bottle yet carry a full 3 litre camelback with the entire world in it - because they can.

just contributes to sore bums and backs

It will move your centre of gravity upwards slightly which is generally bad for stability. But I alaways use a camel back - I cant stand stuff hanging off the bike where it can bounce off, get damaged etc. It also adds more places for mud to collect which adds weight - is more difficult to clean - and reduces life. Also looks rubbish.

lower centre of gravity.

weight on the bike will make the bike less maneuoeueuoverable, but you more so. and vice versa, depends whether you mean the 'bike' or you and the bike.

yet carry a full 3 litre camelback

Who says you have to fill it up?
I rarely carry more than a litre - but its there if you need it.

so is my bottle...

and if its a long ride i might carry two 😉

Who says you have to fill it up?

Some people on here certainly seem to think they need 3l for riding around a trail centre. Though what's worse is that they also seem to think they need to take a full workshop tool kit with them.

I think bottle or camel back boils down to personal preference and riding type....but tools tubes pumps etc is really not going to last hanging off a bike in this country - especially if you leave it on the bike when you clean it. I have one of those under seat bags for the road bike but seems like a bad idea for anthing else.

...and what about your lunch? shove it all in one bag and then add water
simples - all in one place and protected

If it's on the bike then it's either unsprung mass, or less well sprung mass, which will cause the bike to be less smooth over the rough stuff and have less grip when cornerning or braking. But when climbing it's often more pleasant having the weight on the bike rather than on your back. What matters more to you? Uphill or downhill? Covering miles or shredding the gnarr? 😉

My stuff is a smaller percentage of my body weight than it is of the bike, so it goes on me.
As for the haters - some of us sweat like a fat lass in a chocolate factory and need way more hydration than fits on a bike frame.

In addition...

It's all down to your style of riding isn't it?
If you're going for a country bimble along mostly fire tracks, then stick all the weight on the bike.
If you're ducking and weaving the bike down roots and rocks and through trees, I'd want the bike as maneuverable as possible, and accept the weight on my back.

On the road bike I stick all I can on the bike - bottles and tools. Why - because I'm unlikely to be swinging that bike this way and that....

DrP

slight troll, with hint of seriousness:

dehydration is good for you.

you've got to lose a LOT (litres) of water before it reduces your performance by any measureable amount, and if you lose litres of water, you're lighter, so can afford a little loss in performance.

ahwiles

Agreed - Iv stopped taking water on my 22 mile commute to work to save weight as the distance is bordering on impracticle and need to save as much time as possible. I drink as much water as I can before setting off and then Im fine - dont get thirsty at all - just hungry. Its early morning and late afternoon so dont sweat much.

you've got to lose a LOT (litres) of water before it reduces your performance by any measureable amount, and if you lose litres of water, you're lighter, so can afford a little loss in performance.

Guff. Far too many variables in ride / conditions / fitness etc for you to say that so broadly.
My performance degrades badly on a day of cycling (or anything else) if I dehydrate. All experience (inc extended desert conditions with lots of others to observe) tells me hydrations is good. You do what you want but I've suffered extensive dehydration before and would rather manage to avoid that.

back to the OP. If you put the stuff in the camel bak then the bike becomes more manoeuvrable. But you get a bit top heavy.

On the whole I prefer putting stuff in the camel bak rather than on the bike. Main reason is I keep the camelbak in the house and I can be sure I've got the things I want in it before setting off. Another reason is I used to find stuff would rattle around or drop off the bike (pumps, bottles, seat wedge bags...).

On 3L of water and bottles and dehydration, use the water container you prefer and drink when you're thirsty. [url= http://www.bmj.com/content/345/bmj.e4737 ]This piece[/url] in the BMJ has a few things to say about sports drink myths. Unfortunately, it is a piece of 'pay to view' research so non-subscribers don't get the full story.

xtended desert conditions

If it's on the bike then it's either unsprung mass, or less well sprung mass

you've got to lose a LOT (litres) of water before it reduces your performance by any measureable amount, and if you lose litres of water, you're lighter, so can afford a little loss in performance.

Any evidence for this?
As there is plenty of evidence to the contrary i.e 5% loss in total water, (which for a 70kg male is likely to be only 2-3L) can have performance impact.

DrP

never understood the facination with camelbacks

For MTB I think your best with a backpack or camelback as you move the bike around under you much more (or should be). On a road bike my preference is to have everything on the bike.

cheers for all your feedback

ahwiles - Member

dehydration is good for you.

you've got to lose a LOT (litres) of water before it reduces your performance by any measureable amount, and if you lose litres of water, you're lighter, so can afford a little loss in performance.

Hydration is actually super important. A 2% drop, and over, in body weight (through dehydration) has a measurable effect on performance.

My bike is too rad to hold a bottle.

And it would get covered in cack almost instantly which I don't want to put in my mouth.

.

but tools tubes pumps etc is really not going to last hanging off a bike in this country - especially if you leave it on the bike when you clean it

Why? I often put a spare tube and co2 pump on the back of my seatpost, hose it off when I wash the bike, so it's clean again. Why wouldn't it last?!

This regarding bottle use ----->

And it would get covered in cack almost instantly which I don't want to put in my mouth

1) A lighter bike feels better, more responsive and gives a far mor enjoyable ride. That's what we do it for (and spend a fortune on lightweight parts)

2) A camelbak is a more convenient way to have a drink when you want to and will also carry your jacket when you get hot.

3) If you're going to mention physics you should refer to mass, not weight.

Who says you have to fill it up?

Regardless, an empty Mule weighs about the same as a full smallish bottle.

3) If you're going to mention physics you should refer to mass, not weight.

I think it's safe to assume the above is all on Earth.

empty Mule weighs about the same as a full smallish bottle.

Wow that would have to be a small bottle - yakult?

 

MULE = 590g
500ml + 100g bottle

You could take a full 7 pack of Yakult for about the same if that's what you're after though.

100 gram bottle. With 500ml water in.

Itll only be half full surely.

750ml bottle weighs between 50 and 80 grams and throw in about 25 grams for a cage

Job jobbed , i have fluids and you have an empty bag.

Also camelbak list the mule as being 860 grams.

never understood the facination with camelbacks

I'll field this one- it's because drinking from bottles covered in crap is rubbish. Carry more, in comfort, and cleanly, without weighing down your bike, or ever losing a bottle. What's hard to understand?

The thing about riding with the minimum of kit, is that sometimes it turns out not to be the minimum. You run short of water, or get one more puncture than you can deal with, or it rains and you have no jacket, or it doesn't rain and you have nowhere to put your jacket... Camelbaks remove a lot of the ways that rides go wrong. Random passing Northwinds with camelbaks fix problems for people who've come out without kit they later want.

Drinking on a ride isn't just about avoiding negative performance issues from dehydration- it's largely about not being thirsty. Hands up everyone here who only eats when they absolutely need to, rather than when they want to? Why drink differently?

It's only unsprung mass is it's mounted on the wheel side of the suspension or you're riding a rigid bike, in which case so is the rider. If it's a full susser and it's mounted on the frame side of the suspension then it's sprung mass, no matter where it's mounted, on rider or bike.

The longest travel and best suspension on any bike is the rider's arms and legs. Mass added to the rider's torso is far more effectively suspended than having that mass on the frame of a downhill bike, let alone on a shorter travel full sus, hardtail or rigid bike.

I've never lost my camelback on a rough descent.
Lost a few bottles though.

I've never lost my camelback on a rough descent.
Lost a few bottles though.

I regularly lose my bottle on a rough decent.

I've never lost my camelback on a rough descent.
Lost a few bottles though.

I've never bought a £60 water bottle.
Bought a .... etc 🙂

buzz-lightyear - Member
...And it would get covered in cack almost instantly which I don't want to put in my mouth.

You can get bottles with lids - the only sort I use.

But the best place for fluids is inside you. I fill up before I go.

I'll field this one- it's because drinking from bottles covered in crap is rubbish. Carry more, in comfort, and cleanly, without weighing down your bike, or ever losing a bottle. What's hard to understand

Good cage. Means ive never lost a bottle even on the roughest descents - kilbo path or spooky gnar wood ! - except my aero bottle on my tt bike - that was user error.

Bottle covered i crap . Do you aim for dog eggs ? - my mate did ride through once and covered his bike and the roof of his mouth in dog egg. Drinking from the bottle wS the least of his worrys.

I cant think what you might have in your bag that i might want on a ride . Do you care spare mechs or handle bars - i may bend or snap those on a ride. Everything else is repairable with my multi tool , pump and tube. Which all go in the pockets of my jersey.

But then i do notice on here that many folk are in the reactive maintainance camp so i can see why you would want to carry the kitchen sink on your back in that case.

Oh just minded - biggest revelation in drinkng bottles is camelback podiums. Pull it out , give it a squeeze and voila clean nozzle 🙂

I cant think what you might have in your bag that i might want on a ride ...multi tool , pump and tube

then you've got an extra clothing, short blasts in summer or consistently cold winter days not much need but changeable conditions eg night rides where it starts off warm then the temp drops, or those typical UK rainy/sunny/windy days you may need something. Racers seem to manage with just lycra but they are going hell for leather throughout the race generating a huge amount of body heat, average stwer is a damn sight slower and stops for chats/lunch etc

Bottle users get pretty adept at grab/swig/replace but it still doesn't beat having a bite valve a few inches from your mouth

But this is all personal choice, if you're never more than a couple of miles form your house/car minimal tools and a bottle sounds reasonable to me.

Bottle may be fine for you trail rat and not having a backpack on is certainly better ergonomics but lots of people like the versatility of packs and you can't argue with them on that point.

*will try to avoid hyperbole

it was 6am .... i was just being dificult 😉

I've never lost my camelback on a rough descent

"a second tube if its a long, middle of nowhere ride (flatting 2 tubeless tyres or destroying 2 tubes is pretty damn rare but it will leave you stranded),"

what if you flat three times ?

i once punctured 5 times in one 4 hour race in durham was horrendous. had to keep going as it was a multisports adventure race over 2 days and this was the last event. damn quarry stone and paper thin rocket rons - sliced through like hot butter knife through brie. BUT i never once lost my bottle - even on the steep stuff 😉

what if you flat three times ?

DrP - Member

" you've got to lose a LOT (litres) of water before it reduces your performance by any measureable amount, and if you lose litres of water, you're lighter, so can afford a little loss in performance."

Any evidence for this?
As there is plenty of evidence to the contrary i.e 5% loss in total water, (which for a 70kg male is likely to be only 2-3L) can have performance impact.

DrP

'only 2 to 3 litres' - "ONLY" **** me, that's a LOT of sweat.

chief9000 - Member

Hydration is actually super important. A 2% drop, and over, in body weight (through dehydration) has a measurable effect on performance.

so does carrying enough water to stay 'perfectly' hydrated.

like i said, i'm trolling a little, of course drinking is important, but you've got to sweat a lot before the impact on performance can be measured.

'only 2 to 3 litres' - "ONLY" **** me, that's a LOT of sweat.

[url= http://www.sciencelearn.org.nz/Contexts/Food-Function-and-Structure/Sci-Media/Images/Balancing-our-daily-water-needs ]First google hit[/url] suggests at rest we sweat .45L and exhale .35L a day.

trail_rat - Member

Everything else is repairable with my multi tool , pump and tube.

It is an excellent tube which repairs more than one flat, I should get one of those.

no its a "superior" branded tube 😉

You'll sweat less if you buy a road bike and get properly fit.

In the hills you can just drink from streams; it's far nicer than tap water.

Defo off the bike for singletrack stuff, on bike for distance. Ref the comments about carrying too much in a CB, it all depends on how far you a re going and who you a re with, me;

Topeak McGuyver
Leatherman
Drop out
Zip ties
Tape (electrical)
kitchen knive
tube
First field dressing
tourniquet
pump
6mm hex (spares)
4mm hex + stars (spares)
washers
patches
bladder
space blanket

so far in the last 3 months they've all been used to get others out of a pickle. (excpet FFD and TQ...thankfully)

First google hit suggests at rest we sweat .45L and exhale .35L a day

Right... so say you're out for 3 hours, that's 0.1l sweated and exhaled as 'normal'. So... near as dammit sod all!

If you breathe and sweat at your average rate while riding, sure.

First google hit suggests [b]at rest[/b] we sweat .45L and exhale .35L a day

no idea how much it is during exercise, I was just pointing out we exhale (and pee of course) water aswell, I was surprised how high the exhale figure was next to sweating, wonder if it's proportionally similar during exercise aswell or whether sweating becomes a much higher figure compared.

If you breathe and sweat at your average rate while riding, sure.

No no, you misunderstand. The point was "it's not about how much you sweat, just through the normal course of life you lose tonnes of sweat every second, therefore I need a 3 litre Camelbak to get me round one lap of the Twrch trail".

Just observing that's as near as dammit insignificant in the 'how much fluid did I lose whilst riding' debate.

ahwiles - Member

'only 2 to 3 litres' - "ONLY" **** me, that's a LOT of sweat.

chief9000 - Member
Hydration is actually super important. A 2% drop, and over, in body weight (through dehydration) has a measurable effect on performance.

so does carrying enough water to stay 'perfectly' hydrated.

like i said, i'm trolling a little, of course drinking is important, but you've got to sweat a lot before the impact on performance can be measured.

Well mr ahwiles, in the end its all down to you and your personal preferences. So you can choose whether you carry water or not and make your own decision. The generally accepted IOC issued guidelines for sport and recommend that you rehydrate with a litre of fluid per hour of sport.

Should you carry water? like I said up to you. If you are about for an hour, probably not that critical, however after 2 hours I would say that it would become important. You ask whether carrying the water would adversly affect your performance, of course there will be a trade off . However if you open your mind a little, I would say that ultimately carrying the water could provide you with an additional longer term advantage.

At the moment when you are your strongest, you are carrying more water and thus weight. This means pushing your muscles that much more beyond their limits (in other words training). Next time you are out you will be a shit load faster then you can go and tell your mum that you beat all your friends in the race at school. 😉

Bullseye!

Always keep everything on my back, not as if tools, spares and water are heavy. Usually got a litre or 2 (bottles, as in volvic or whatever) In my bag, rarely more.