How much does luggage slow you down?

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tatanab
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Re: How much does luggage slow you down?

Post by tatanab »

quilkin wrote:I was attempting to estimate the effect on my time for a 1000-mile trip across France: i.e. can I do it comfortably (enjoying it) in two weeks?
70 miles a day average. I would not consider that a problem unless in very hot weather. I've been totally wiped out by heat after only 50 hilly miles before now. Me aged 63, touring machine weighs about 65lbs with camping kit, bidons etc. I admit that I slowed down a bit this year and only averaged 60 miles a day for 1000 miles, but then I've done little other riding this year. You can do your own km and kg conversions :)

I also find that I ride further and more easily on tour simply because the land is not familiar so I do not know that the next 10 miles are on a rotten roller of a road with an appalling surface. Ignorance is bliss - don't worry about it.
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Re: How much does luggage slow you down?

Post by Vorpal »

I'm not too worried about how much slower I am with extra weight. I am, however, somewhat worried about how much toll it takes on me, on a long day.

Yes, I go a bit slower on the hills. So what? It's leisure. I'll spend more time stopping to take pictures.

What I don't want is to end the day completely knackered after 50 or 60 miles, because that's what too much weight will do to me. If I haul camping gear, etc. behind the tandem with Littlest as stoker and Mini V on her own bike, it's just as well that we go at kid pace, because I can't cope with much faster. Yes, I can pedal faster, but I'll end the day too tired for a second day of cycling.
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ChrisF
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Re: How much does luggage slow you down?

Post by ChrisF »

Vorpal wrote:I'm not too worried about how much slower I am with extra weight. I am, however, somewhat worried about how much toll it takes on me, on a long day.

Ye, I too have the concern of the effect of luggage over a long day, which may somehow count more than an hour's ride (subjectively at least!). In theory, if one sticks to a 'easy' 120 watts all day it shouldn't make any difference, but I guess if you have a lot more extra weight (e.g. pulling a trailer and a child) then it becomes impossible to use as little as that when you need to climb (and every time you accelerate from a stop), so you're often having to use a lot more power - which ends up with you being knackered at the end of the day.
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Re: How much does luggage slow you down?

Post by phil parker »

My average, as calculated by my Garmin, is generally 2 - 3 mph slower when touring (camping, up to 17 Kgs) than when riding without luggage. Of course that accounts for other factors than additional weight alone, but it allows me to understand and plan my routes better!
David881
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Re: How much does luggage slow you down?

Post by David881 »

Does the weight of the rider make a difference? For example an extra 5k of luggage is proprtinally a much larger increase for a rider weighing 60k than one riding 80k, and therefore conceivably could have a different effect on performance
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Mick F
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Re: How much does luggage slow you down?

Post by Mick F »

Yes, it must.
I wonder if we should be talking about over-all weight to power ratio?
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Re: How much does luggage slow you down?

Post by Bmblbzzz »

I do think – though I certainly don't have any figures to demonstrate – that we should differentiate between rider weight and off-rider weight. So if two riders both develop 250W and have the same total (rider + bike + luggage) weight, A weighs 60kg, bike 15kg, luggage 20kg = 95kg; B weighs 80kg, bike 10kg, luggage 5kg = 95kg; rider A is going to be more affected by the weight he is propelling. So, yes, luggage weight should be considered in proportion to rider weight and power, but it's not a straight ratio.
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[XAP]Bob
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Re: How much does luggage slow you down?

Post by [XAP]Bob »

Bmblbzzz wrote:I do think – though I certainly don't have any figures to demonstrate – that we should differentiate between rider weight and off-rider weight. So if two riders both develop 250W and have the same total (rider + bike + luggage) weight, A weighs 60kg, bike 15kg, luggage 20kg = 95kg; B weighs 80kg, bike 10kg, luggage 5kg = 95kg; rider A is going to be more affected by the weight he is propelling. So, yes, luggage weight should be considered in proportion to rider weight and power, but it's not a straight ratio.

If both weights are the same and the power is the same, then the only difference is in aero and/or rolling resistances.

The thing is that the larger rider is probably able to push more power...
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Mick F
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Re: How much does luggage slow you down?

Post by Mick F »

We have two cars, a Renault Clio 1.6 16v @ 110bhp, and a Fiat 500 Twinair @ 85bhp.
The Clio is a heavy car due the high spec, but is quite nimble, though not "quick".
The Fiat is very light and very quick, and is wonderful fun to drive. :D

The Clio has a towbar, and yesterday I collected ten back of coal in the trailer. Clio managed very well, even with the horrendous hill up to our place.

The Fiat doesn't have a towbar (yet) though we may fit one in the future. However, I doubt very much that the car would cope so well with even eight bags of coal .......... or even seven. The Clio leaves it standing when it comes to plain "grunt" and pulling power.

It's not just power to weight ratio, it's more to do with the power curve and how the power is put down.
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hondated
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Re: How much does luggage slow you down?

Post by hondated »

Mick F wrote:Having towed a heavy trailer up and down this fair country of ours, I can say quite categorically that weight makes little difference to overall speed.

It's a surprising fact that it may slow you down on acceleration and up steep hills, but you gain going down the hills and on the flat it doesn't affect anything. Overall, it makes little difference at all.

Given this as been written by you Mick I cannot query it but I find that astonishing.
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horizon
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Re: How much does luggage slow you down?

Post by horizon »

David881 wrote:Does the weight of the rider make a difference? For example an extra 5k of luggage is proprtinally a much larger increase for a rider weighing 60k than one riding 80k, and therefore conceivably could have a different effect on performance


I would have thought it depends on how much of the weight of the heavier rider is muscle. A larger person has the build to move his/her own weight and more but that will vary with the person. How much of Mick F's Clio weight is engine and how much is just extra stuff? AIUI we always (reasonably) assume that the heavier/larger rider is proportionally the same as a lighter/smaller rider. But that obviously isn't always the case.
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horizon
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Re: How much does luggage slow you down?

Post by horizon »

hondated wrote:
Mick F wrote:Having towed a heavy trailer up and down this fair country of ours, I can say quite categorically that weight makes little difference to overall speed.

It's a surprising fact that it may slow you down on acceleration and up steep hills, but you gain going down the hills and on the flat it doesn't affect anything. Overall, it makes little difference at all.

Given this as been written by you Mick I cannot query it but I find that astonishing.


That may be the 10 kg rule in play: 10 kg is nothing to the average rider. 30 kg may be not be very much to a strong rider. He still had to haul himself and the bike up the hills so the extra weight may not be all it seems. I've got a 20 kg advantage on someone weighing 96 kg and his weight might be flab while mine is well obviously pure muscle. :wink:
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Mick F
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Re: How much does luggage slow you down?

Post by Mick F »

If the road is flat and you ignore wind resistance, weight means nothing to top speed or average speed. Acceleration is affected, but not speed.

If you are a strong rider, you can haul a load up a hill without too much stress and strain. You may not be fast, but you have power. The skill and ability will win the day.

Just watch a good rider climb a hill. I don't mean a racer, I mean a good experienced rider. He'll know exactly which gear to be in to best effect, and he'll know just how hard to turn the cranks. He'll also have good technique in movement and be able to use his power efficiently. He'll have big lungs and strong legs, he won't get fraught and upset with the prospect of the hill. He'll relax and take it in his stride, and he won't rush at it like a bull at a gate.

Now, watch an inexperienced rider. He'll fret and worry, he'll not be "at one" with his bike and he'll tire easily. He'll be in the wrong gear, hold back on the downhills, and try to go too fast on the flat. He'll sway this way and that, and his riding position will be inefficient.

I spent miles and miles over weeks on end towing a concrete block along the lanes of Devon and Cornwall in an effort to be able to absorb the extra weight. In the end, it became "easy" and natural, and I was well prepared for my forthcoming tour. I did the same with the Raleigh Chopper and TBH I found the JOGLE quite easy. It was the awful Chopper saddle that slowed me down! :lol:

Weight is weight. You cannot argue this point, but you can get used to it so you don't notice, and you can cope with it through technique and practice.
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Brucey
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Re: How much does luggage slow you down?

Post by Brucey »

Mick F wrote:If the road is flat and you ignore wind resistance, weight means nothing to top speed or average speed. Acceleration is affected, but not speed.


that ignores rolling resistance, which is always proportional to the total weight. For many riders this is a small portion of the whole, but it needn't be; CJ has pointed out in the past that the least powerful riders have the greatest proportion of their effort expended against rolling resistance, and are therefore arguably most affected by it.

It will vary with the rider but if you are doing around 10mph then it is likely that about 50% of your effort is going against rolling resistance. Thus if you increase the weight by 10% you increase overall resistance by around 5%, and the speed will drop similarly.

A more powerful rider (doing, say, 20mph) might only be expending about 20% of their effort against rolling resistance, so a 10% increase in that will only change the total drag by about 2% at that speed, and the actual speed change will be less than that.

So what I'm saying is that the effects of weight increase are certainly not the same for every rider and should not be assumed thus; they can in fact be very different indeed.

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Mick F
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Re: How much does luggage slow you down?

Post by Mick F »

Brucey wrote:It will vary with the rider but if you are doing around 10mph then it is likely that about 50% of your effort is going against rolling resistance.
50% sounds hugely high.

On a flat smooth road I reckon that at 10mph there is negligible rolling resistance (to me in my experience) ............. so long as you have suitable tyres.

Thick knoblies or soft wide tyres, I may agree with you.
Mick F. Cornwall
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