# Bike weights.....



## RegG (6 Apr 2016)

Ok, I know this is going to open loads of cans of worms but, having just bought a digital luggage scale for our hols, I thought I would try it out on my bike, just out of interest.......

My 2015 Giant Defy 0 (now with Ultegra crankset, cassette and brakes, plus Vittoria Session wheels/Rubino tyres, Selle Italia G2 saddle, and Topeak aero wedge bag) weighed in at 9.6kg.

Who else has weighed their bike and what was the result?


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## RoubaixCube (6 Apr 2016)

Ive been thinking about doing this but i have no idea where my digital scales are.


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## Rooster1 (6 Apr 2016)

Would love to weigh my 2008 Defy 2, I've tried to lighten it up with a few upgrades but I reckon its heavy still.


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## Crackle (6 Apr 2016)

My road bike, a steel frame 631 is 10.5kg
My mountain bike, alu, a Kinesis FF29 is 11kg
My Marin bear valley chromo is 14kg


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## Unimaginative (6 Apr 2016)

Weighed my Rose recently; I've got the 2015 version of https://www.rosebikes.co.uk/bike/rose-xeon-team-cgf-3000-818234/aid:818294 - Ultegra 6800, Compact, 11-28, Ritchey WCS Seatpost, Handlebars and Stem, Con GP4000SII 25mm tyres but I've replaced the saddle with a Specialized Romin Evo Expert Gel, added M540 (SPD) pedals, two bottle cages and a topeak aero medium wedge containing a Topeak Hexus 2, two spare inner tubes, park tools glueless patches and a quick link. 

All together, this comes to 7.9Kg


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## mjr (6 Apr 2016)

I posted all the ones I've weighed to https://www.cyclechat.net/threads/bike-weight.191695/


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## T.M.H.N.E.T (6 Apr 2016)

Disc braked road bike 7.6kg


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## Dave7 (6 Apr 2016)

My Defy 1 carbon seems heavy compared to these weights @ 79 Kg.
Am I supposed to be sitting on it ??


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## si_c (6 Apr 2016)

Steel road bike with Mudguards, Saddlebag etc, 13kg, without 10.5kg. Fat lump on the saddle 100kg.


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## mjr (6 Apr 2016)

si_c said:


> Steel road bike with Mudguards, Saddlebag etc, 13kg, without 10.5kg. Fat lump on the saddle 100kg.


Enjoyment from riding it, priceless?


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## si_c (6 Apr 2016)

mjray said:


> Enjoyment from riding it, priceless?



Pretty much


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## Smokin Joe (6 Apr 2016)

Recumbent trike, about eighteen kilos.


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## winjim (6 Apr 2016)

CdF 15kg
Titanium superbike 9kg

Measured on a spring balance with no great precision and no means of calibration other than the knowledge that I wasn't charged for excess baggage last time I took a flight.


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## NorthernDave (6 Apr 2016)

Road bike - with lights, mudguards, saddlebag, etc 12.5kg (9.9kg without all that lot)

Hybrid - with lights, mudguards, saddlebag, etc 16.5kg (13.5kg without)

The real problem is the 95kg of lardass I then balance on top...


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## winjim (6 Apr 2016)

winjim said:


> Titanium superbike 9kg


Quick calculation on the back of a fag packet using mainly claimed weights:

Frame 1375g
Fork 350g
Wheels 1757g
Tyres & tubes 600g
Skewers (estimate) 150g
Groupset 2096g
Pedals 266g
Saddle 230g
Seatpost 135g
Seatclamp 28g
Headset 108g
Stem 225g
Bars (estimate) 200g
Bar tape negligible
Bottle cage negligible
Stack spacers negligible
Gives a total of 7.5kg. Add 10% for inaccuracies / wishful thinking in manufacturers claimed weight, so call it 8ish kg. Precision of spring balance and my weighing technique +/- at least half a kilo so that could be about right.

Rider 65kg


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## Shut Up Legs (6 Apr 2016)

The total weight of mine is about 87kg. That's typically what I'm dragging up the hills, and includes the bike, attachments and myself. Any other weight measurement is pointless.


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## Crandoggler (6 Apr 2016)

About 120kg all said and done. Poor wheels.


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## Tim Hall (6 Apr 2016)

Dave7 said:


> My Defy 1 carbon seems heavy compared to these weights @ 79 Kg.
> Am I supposed to be sitting on it ??


Try standing and report back.


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## Pale Rider (7 Apr 2016)

I'd like to weigh my Rose trekking ebike, but the local weighbridge would charge me to do it.


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## Elybazza61 (7 Apr 2016)

Planet X XLS in 1X10 mode with 'guards and lights on is 9.3kgs on the works shipping scales.

Ridley Icarus(ally frame) is approx 9.0kgs

Weigh steel ss is about 10kgs

Ridley Helium sl hasn't been weighed yet in with the Hunt wheels but was 6.8kgs with the Zondas.


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## huwsparky (7 Apr 2016)

martint235 said:


> No it's not. Climbing has little to do with weight and more to do with power-weight ratio. I weigh in at 104kg but I'm fairly handy at going up hills.


Buy what's that got to do with the weight of your bike?


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## martint235 (7 Apr 2016)

huwsparky said:


> Buy what's that got to do with the weight of your bike?


Not a lot but then I don't think the weight of a bike has that much to do with anything. It's a small percentage of the total weight.

The weight of the rims and the tyres is probably quite important though cos there's all complicated maths to do with inertia etc that involves multiplications and things.


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## huwsparky (7 Apr 2016)

martint235 said:


> Not a lot but then I don't think the weight of a bike has that much to do with anything. It's a small percentage of the total weight.
> 
> The weight of the rims and the tyres is probably quite important though cos there's all complicated maths to do with inertia etc that involves multiplications and things.


True, and I agree with you (but let's not forget the title of the thread!) The weight of the bike is largely irrelevant. However, a lighter bike does feel different, but that doesn't necessarily mean it's all that much faster. I'm sure I read somewhere that weight saved on wheels and tyres is worth 4 times that of the rider/bike weight saving.

Having just bought a new bike which is 2kg's roughly lighter than my old one I can say that it does 'feel' more responsive on steep hills. Around 400g of that 2kg's has come directly off the wheel/tyre combo which I'm guessing is the main difference in feel.


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## Ajax Bay (7 Apr 2016)

huwsparky said:


> I read somewhere that weight saved on wheels and tyres is worth 4 times that of the rider/bike weight saving.


Do you believe this (ie what you say you've read somewhere) and if so, please explain what 'worth 4 times' means in reality, and how that 'worth' presents itself when riding?
If you lost 2kg of weight off your body weight, would you expect your older (2kg heavier) bike similarly to 'feel more responsive'?


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## Illaveago (7 Apr 2016)

I have just weighed my 1970's Holdsworth Record, 531 plain gauge tubing, Brooks leather saddle, 27by 11/8 tyres and tubes, GB stem and bars, Weinmann centre pull brakes and levers, Campag Record rear derailleur, Ta Stronglight double clanger, pedals and rat traps and SS short mud guards.
Total weight 10.2 KGS.


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## si_c (7 Apr 2016)

Illaveago said:


> I have just weighed my 1970's Holdsworth Record.
> Total weight 10.2 KGS.



That just amuses the hell out of me.


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## Ajax Bay (7 Apr 2016)

What are the wheels on your Holdsworth @Illaveago , Maillard; Weinmann?


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## Dogtrousers (7 Apr 2016)

Bike weights? Why in earth would you want to make your bike heavier? I expect Wiggle sell them.


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## Ajax Bay (7 Apr 2016)

Dogtrousers said:


> Why in earth would you want to make your bike heavier?


To get the bike above the UCI minimum, obviously.


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## huwsparky (7 Apr 2016)

Ajax Bay said:


> Do you believe this (ie what you say you've read somewhere)


No, I don't generally believe most things I read with regard to improving cycling performance etc, as it's usually to try and sell something. However it's totally conceivable that the best way to shed weight in climbing terms would be from the parts of the bike that actually move. The '4 times' bit though is just something I read, not something I would take as factual.


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## Illaveago (7 Apr 2016)

Ajax Bay said:


> What are the wheels on your Holdsworth @Illaveago , Maillard; Weinmann?


Fiamm Campag hubs or one is the rear was a replacement.


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## Tim Hall (7 Apr 2016)

Ajax Bay said:


> Do you believe this (ie what you say you've read somewhere) and if so, please explain what 'worth 4 times' means in reality, and how that 'worth' presents itself when riding?
> If you lost 2kg of weight off your body weight, would you expect your older (2kg heavier) bike similarly to 'feel more responsive'?


The closest I can find is that weight lost from bike wheels costs you up to 4 times as much as weight lost else where as those weight weenie, minimum spoke count wheels are fearsomely expensive. They spin up well though and are incredibly responsive though. <runs away>


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## nickyboy (7 Apr 2016)

huwsparky said:


> No, I don't generally believe most things I read with regard to improving cycling performance etc, as it's usually to try and sell something. However it's totally conceivable that the best way to shed weight in climbing terms would be from the parts of the bike that actually move. The '4 times' bit though is just something I read, not something I would take as factual.



Here's the deal with rotational mass v non-rotational mass.

If you aren't accelerating, rotational mass has exactly the same effect as non-rotational mass. So, climbing up a hill (I guess you're not accelerating!) a kg of wheel rim mass has exactly the same effect as a kg of, for example, bottom bracket mass

If all your wheel weight was in the rims, the effect of a kg off the wheel mass is about the same as 2kg off the non-rotating mass in terms of effect on your ability to accelerate...very little

The position of the mass on your bike only matters when accelerating or decelerating. Less mass on the rotating bits rather than on the non-rotating bits make acceleration easier (and deceleration less easy). But if you do the maths, unless you're one of those crit riders constantly accelerating and decelerating, the effect is so small as to be virtually unmeasurable. The actual rate of acceleration by a cyclist is glacially slow


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## Crandoggler (7 Apr 2016)

huwsparky said:


> Buy what's that got to do with the weight of your bike?


You're literally spending thousands of pounds to gain an advantage that having a good clear out and removing your water bottle will achieve.


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## Lonestar (7 Apr 2016)

I think my bike has put weight on.


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## Dogtrousers (7 Apr 2016)

Ajax Bay said:


> To get the bike above the UCI minimum, obviously.


Ah yes, the UCI. They're always nagging me to make my bike heaver.


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## huwsparky (7 Apr 2016)

Crandoggler said:


> You're literally spending thousands of pounds to gain an advantage that having a good clear out and removing your water bottle will achieve.


1. What are you taking about?

2. Why would that bother you IF I or anyone ELSE, did want to spend money on a nice 'lighter' bike?

3. I can't go very far without water so your point is kind of pointless anyway.

4. I suppose I could ditch the multitool, tubes and pump, enough of a 'clear out' for you? I don't know anyone who carries anything on their bike that doesn't need to be there anyway.

A lot of threads on this forum get taken on some complete weird tangent vaguely resembling what is supposed to be about. Why?


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## Ajax Bay (7 Apr 2016)

huwsparky said:


> threads on this forum get taken on some complete weird tangent vaguely resembling what is supposed to be about. Why?


Because contributors are here to 'chat' - and for this thread (what does your bike weigh?) there are all sorts of 'so whats' and secondary lines of discussion. People even say they've read things, quote them, and then say 'oh no, I don't believe it'. Weird? No. Tangential? Probably. Vaguely resembling a fact? Possibly, but probably not in the case of your quote "weight saved on wheels and tyres is worth 4 times that of the rider/bike weight saving".


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## Crackle (7 Apr 2016)

Using the square root of inverse snobbery and multiplying by a factor of smug, it's proven that lighter bikes go faster, even when prime weight increases exponentially to the value of pie plus.


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## Ajax Bay (7 Apr 2016)

Far too chatty and tangential, and as for 'weird', definitely @Crackle


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## huwsparky (7 Apr 2016)

Ajax Bay said:


> Because contributors are here to 'chat' - and for this thread (what does your bike weigh?) there are all sorts of 'so whats' and secondary lines of discussion. People even say they've read things, quote them, and then say 'oh no, I don't believe it'. Weird? No. Tangential? Probably. Vaguely resembling a fact? Possibly, but probably not in the case of your quote "weight saved on wheels and tyres is worth 4 times that of the rider/bike weight saving".


I don't think saying that not taking a water bottle or spares is of any contribution to this thread as you have to take them IMO.

Debating weather/what differences lighter wheels etc is of use to the thread as it's about weight, but we've all been taken away from that for some reason and moved on to not taking water bottles to save weight which is not really comparable.


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## Jody (7 Apr 2016)

huwsparky said:


> A lot of threads on this forum get taken on some complete weird tangent vaguely resembling what is supposed to be about. Why?



Tinterwebz innit.


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## Jody (7 Apr 2016)

huwsparky said:


> I don't think saying that not taking a water bottle or spares is of any contribution to this thread as you have to take them IMO.



I get the impression 'clear out' meant poo and not removing things from a saddle bag.

Could be wrong though.


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## Jody (7 Apr 2016)

Back to the OP. My push iron, full suss without tubes and with SPD's comes in at 27lbs


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## si_c (7 Apr 2016)

Crackle said:


> Using the square root of inverse snobbery and multiplying by a factor of smug, it's proven that lighter bikes go faster, even when prime weight increases exponentially to the value of pie plus.



In my case weight definitely increases due to pie plus. Usually chips and mushy peas.


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## Dogtrousers (7 Apr 2016)

I think this has been posted here before: How much time does extra weight cost on Alpe d’Huez?
A guy rode up Alpe d'Huez on different weight bikes, including one with water-filled tyres, and one with soft tyres. He took different amounts of time. Unfortunately he also recorded different average power outputs too, which makes the results a bit hard to read.
The results: he went a bit slower on heavier bikes, but he also returned higher wattage on the light bike. Conclusion? A light bike makes you try harder


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## huwsparky (7 Apr 2016)

Dogtrousers said:


> A light bike makes you try harder



Quite possibly correct. After spending a lot of money buying a bike that makes the completed weight 1 - 2% lower in sure one would find an extra watt or two somewhere!

GCN also done similar test, the only way to prove the theory fairly would be to fit a say 300w motor to bikes of different specs and let them go up a hill. Anything short of this wouldn't really be meaningful/accurate.


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## winjim (7 Apr 2016)

So my bike that is a quarter of my body weight is just as easy to get up hills as my bike that weighs half that, and I really should be concentrating on increasing that proportion by making myself dangerously underweight? I'm confused


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## Puddles (8 Apr 2016)

Bertha weighs lots.

She weighs less than she used to as Eldest now has panniers so spurious amount of child crap they pile onto my bike has mostly tranfered to his bike. If we are going on a picnic or crabbing type trip then do we include trailer in weight?

I also weigh lots

My basket which doubles has a handbag probably weighs loads too as I don't think I have seen the bottom of it nor it emptied since it arrived.... that also contains spurious random items....


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## Ajax Bay (8 Apr 2016)

winjim said:


> So my bike that is a quarter of my body weight is just as easy to get up hills as my bike that weighs half that, and I really should be concentrating on increasing that proportion by making myself dangerously underweight? I'm confused


Don't think anyone above has suggested that a heavier bike is equally easy to get up the hills (though may depend on gearing). But your bike is not 1/4 of your body weight, in the context of bikes designed to 'get up hills', it's more likely 1/7 or less. So rather than concentrating on reducing the weight of a bike by 1kg, better to lose a kilo of body (or say 1/50 of whatever your mass is now, if greater ). Not that you personally need to, of course.


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## Pat "5mph" (8 Apr 2016)

huwsparky said:


> I don't know anyone who carries anything on their bike that doesn't need to be there anyway.


Hi, pleased to meet you  


That was before I discovered BIG panniers, hehehehe ... and trailers!


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## mjr (8 Apr 2016)

Ajax Bay said:


> But your bike is not 1/4 of your body weight, in the context of bikes designed to 'get up hills', it's more likely 1/7 or less.


Aren't all bikes designed to get up hills? My usual bike is 18kg and I usually weigh less than 72kg.

And like Pat, I've a rather bad habit of just leaving stuff in the 13litre saddlebag...


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## clid61 (8 Apr 2016)

While we're on the subject of " bike weights" , I once had a tandem with a pair of dumb bells on it  Suffice to say it didn't last !


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## Ajax Bay (8 Apr 2016)

This is the Nov 15 - Jan 16 version of this thread:
https://www.cyclechat.net/threads/bike-weight.191695/


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## winjim (8 Apr 2016)

Ajax Bay said:


> This is the Nov 15 - Jan 16 version of this thread:
> https://www.cyclechat.net/threads/bike-weight.191695/


This has been discussed before? Whodathunk?


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## Ajax Bay (9 Apr 2016)

And the 2014 version:
https://www.cyclechat.net/threads/bike-weight.149976/
And a 2013 version (focussing more on body mass):
https://www.cyclechat.net/threads/dont-believe-what-they-all-say-about-weight.129574/


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## Dogtrousers (9 Apr 2016)

Ajax Bay said:


> And the 2014 version:
> https://www.cyclechat.net/threads/bike-weight.149976/
> And a 2013 version (focussing more on body mass):
> https://www.cyclechat.net/threads/dont-believe-what-they-all-say-about-weight.129574/


And your point is what?


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## Ajax Bay (9 Apr 2016)

My point is that if this thread is worth reading for interest and information, then so are the others which covered similar ground but I thought had some GPWM.
I'd like to think that people search for information before starting up a new thread (gear ratios comes to mind), but I think you'd agree that we'd be disappointed.


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## Dogtrousers (9 Apr 2016)

Ajax Bay said:


> My point is that if this thread is worth reading for interest and information, then so are the others which covered similar ground but I thought had some GPWM.
> I'd like to think that people search for information before starting up a new thread (gear ratios comes to mind), but _I think you'd agree that we'd be disappointed_.


I would indeed agree. 

IMO it's an interesting-ish subject, that gets chewed over now and again, sometimes throwing up new info, sometimes with new participants. And it's generally not particularly acrimonious so I personally am happy to go with the flow.

And just to show willing I've just weighed my (large frame) Spa Steel Audax - without tools, lights, lock, handlebar bag or (crucially) me. It was a smidge over 11kg. 

It does have a thin coating of mud from yesterday's ride (that's a job for today)


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## Ajax Bay (9 Apr 2016)

@RegG asked (on a similar thread): ↑
"How are you guys weighing your bikes? Yes, I know scales come in handy but what sort are you using?"
Best answer:


blazed said:


> I put various weights on my left palm, so say I put 8kg in total. Then lift my bike with my right palm, depending which arm goes up or down I know whether its lighter/heavier than 8kg or not. Adjust the weights until you get a balance.


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## Specialeyes (9 Apr 2016)

Ah, but we can't all do that - @blazed was one of the best


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## Ajax Bay (9 Apr 2016)

Was?


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## Specialeyes (9 Apr 2016)

blazed said:


> I used to cycle a lot, I was one of the best.



To revert to topic, I've just been and weighed my Kuota Kiral, with 2 bottle cages, front and rear lights and 25mm Gatorskin Hardshells on: 8.2Kg. 

I suspect my Tarmac's become a gnat's lighter since I put 11-speed 105 and decent wheels on it, but it's attached to the turbo at the moment with the back wheel off!


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## carcharodon (11 Apr 2016)

My bike is a bit on the hefty side, Avanti Circa 1 cx : 11.25 kg...but I need to lose 5 kg's.

Funny thing is it doesn't feel hefty, maybe the Hollowtech BB and alloy frame design? Efficient power transfer to the wheel? I don't know.


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## RobinS (11 Apr 2016)

I weighed my Revolution Country Explorer - it came in at 40.2kg! It does have front and rear racks, lights, mudguards, three bottle cages with full drink bottles, seatpack toolkit, four ortlieb panniers, a barbag, full camping/cooking kit, clothes, some food etc with everything test packed for a three month tour! It only feels heavy if you try to pick it up.


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## Fnaar (11 Apr 2016)

RobinS said:


> I weighed my Revolution Country Explorer - it came in at 40.2kg! It does have front and rear racks, lights, mudguards, three bottle cages with full drink bottles, seatpack toolkit, four ortlieb panniers, a barbag, full camping/cooking kit, clothes, some food etc with everything test packed for a three month tour! It only feels heavy if you try to pick it up.


I have one of those too, with probably a similar weight for touring purposes. It's built like a tank though, and seems fairly indestructible!


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## bozmandb9 (11 Apr 2016)

martint235 said:


> No it's not. Climbing has little to do with weight and more to do with power-weight ratio. I weigh in at 104kg but I'm fairly handy at going up hills.



Not wanting to get involved in the handbags, but not sure about this? I get that power to weight ratio is vital for hill climb races, but surely on a long ride the higher weight will only ever be a disadvantage.


Ajax Bay said:


> Do you believe this (ie what you say you've read somewhere) and if so, please explain what 'worth 4 times' means in reality, and how that 'worth' presents itself when riding?
> If you lost 2kg of weight off your body weight, would you expect your older (2kg heavier) bike similarly to 'feel more responsive'?



I bet if you stick 3.5 to 4kg wheels on your road bike you'll no longer need him to explain what wheel weight matters in reality! Specially when you go up a steep hill!


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## Ajax Bay (11 Apr 2016)

bozmandb9 said:


> bet if you stick 3.5 to 4kg wheels on your road bike you'll no longer need him to explain what wheel weight matters in reality!


I suggest that going up a hill, especially a steep hill, it's the all up weight that matters. Light bike with heavy wheels weighing the same as a heavier bike with lighter wheels will need very similar amounts of power from the same rider to climb the hill. And if you have a lighter rider on a heavier bike she will have to put out the same power (to go up the hill at the same steady speed) as the bloke who's heavier but on a UCI @huwsparky 6.8kg bike, if the bike + rider overall weight is the same. Weight in the wheels matters for acceleration, not at constant speed.


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## HLaB (11 Apr 2016)

I'd love to weigh my 4.75kg TREK Emonda SLR 10, unfortunately I've not got one


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## classic33 (17 Apr 2016)

huwsparky said:


> * I don't know anyone who carries anything on their bike that doesn't need to be there anyway.
> *Why?


On it's own, approx 40 kilo. Loaded, anything upto 380 Kilo.
Fast enough to set speed cameras off on some local inclines, unloaded. And about four grand to replace, new.


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## 2IT (17 Apr 2016)

Just because someone is lightweight does not make that person a good cyclist nor necessarily good at going up hills. One could weigh very little and could have trouble lifting their own weight.

The point of the thread was sharing bike weights. Handy information because some manufacturers have stopped listing weight so this is good.

MOD NOTE:
Some of this post has been Deleted, as it quoted a Deleted post.


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## bozmandb9 (17 Apr 2016)

Ajax Bay said:


> I suggest that going up a hill, especially a steep hill, it's the all up weight that matters. Light bike with heavy wheels weighing the same as a heavier bike with lighter wheels will need very similar amounts of power from the same rider to climb the hill. And if you have a lighter rider on a heavier bike she will have to put out the same power (to go up the hill at the same steady speed) as the bloke who's heavier but on a UCI @huwsparky 6.8kg bike, if the bike + rider overall weight is the same. Weight in the wheels matters for acceleration, not at constant speed.


We weren't specifically talking about going up hills. I would certainly notice a difference between an extra 2kg on my wheels (in fact I massively noticed a 1kg weight reduction, and yes, it certainly felt more responsive. My bodyweight can fluctuate much more than 2kg, and I don't notice the same difference at all. To me, wheel weight is a very important factor. I guess the bottom line is on a typical ride, one doesn't tend to spend loads of time at a constant speed. Junctions, corners, hills, traffic lights, etc all seem to get in the way of this. Not sure about the science, but I would certainly much rather be tacking hills with ultra light wheels, and a couple of kg in my pockets, rather than heavy wheels. Most hills I know have varying degrees of incline, hence acceleration and deceleration.


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## Ajax Bay (17 Apr 2016)

bozmandb9 said:


> I bet if you stick 3.5 to 4kg wheels on your road bike you'll no longer need him to explain what wheel weight matters in reality! Specially when you go up a steep hill!





bozmandb9 said:


> We weren't specifically talking about going up hills.


Well I think you were (see first quote) and I was, specifically. I get that lighter wheels will feel more responsive and also that you don't sense when you've put on a couple of kilos on your (albeit minimal) gut - so you can't "feel" the latter. On a typical ride you *do* spend a lot of time (ie a high percentage) at a relatively constant speed eg 18kph + or - 3 YMMV and the RATE of acceleration is, as @nickyboy puts it it an earlier post "glacially (s)low".


bozmandb9 said:


> Not sure about the science


I think you suggested that weight on the wheels was 4 times weight on the bike/gut. How do you fancy climbing a decent long hill with lighter wheels and 4kg of extra weight in, say, your saddlebag as opposed to your normal svelte self unloaded, with normal wheels?
@nickyboy was dead on:


nickyboy said:


> The position of the mass on your bike only matters when accelerating or decelerating. Less mass on the rotating bits rather than on the non-rotating bits make acceleration easier (and deceleration less easy). But if you do the maths, unless you're one of those crit riders constantly accelerating and decelerating, the effect is so small as to be virtually unmeasurable. The actual rate of acceleration by a cyclist is glacially slow


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## nickyboy (18 Apr 2016)

And just to finally put this issue of rotational mass, acceleration etc etc to bed once and for all.....

Sure you can accelerate up a hill. In doing so, having less mass in the wheels rather than elsewhere on the bike will be beneficial. Of course, when you do the maths, the benefit is incredibly small. Much too small to be felt by a cyclist.

However, it's there....BUT....the opposite applies to deceleration. So when you arrive at a steeper bit and slow down you slow down more quickly with light wheels. It is a nil sum equation. The benefit you get from lighter wheels in being able to accelerate more quickly is given back by decelerating more quickly too


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## Ajax Bay (18 Apr 2016)

Thank you @nickyboy - I considered making the point about increased rotational inertia working both ways (ie during deceleration) but decided it would muddy the point without sufficient benefit. Couldn't you wind entropy into the discussion?


nickyboy said:


> just to finally put this issue of rotational mass, acceleration etc etc to bed once and for all.....


You can dream. Others can dream and TMMV.


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## bozmandb9 (19 Apr 2016)

Got it. Great, that's saved me some money which I shall put into losing more weight from myself! Or at least turning into useful weight (muscle). ;-)


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## carcharodon (20 Apr 2016)

Are manufacturers not disclosing weights as bicycles are increasing in kg's due to cost-cutting? Wheels are commonly the parts that get heavier. Compare models, one make from 2010 - 2014 to now, although there are design factors such as disc brakes that come into it. All the more reason to buy older models...
Unfortunately profit margins rule in the end.


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## Dogtrousers (20 Apr 2016)

carcharodon said:


> Are manufacturers not disclosing weights as bicycles are increasing in kg's due to cost-cutting? Wheels are commonly the parts that get heavier. Compare models, one make from 2010 - 2014 to now, although there are design factors such as disc brakes that come into it. All the more reason to buy older models...
> Unfortunately profit margins rule in the end.


No, probably because it's dependent on a number of factors - size, options selected and so forth. So they have a choice of a complex set of estimates, which add little or nothing to the selling potential, and which involve the risk of disputes with people whose bike actually comes in 2g over the stated weight, or a "minimum weight" which would look good, but be meaningless and result in an arms race with other manufacturers.


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## carcharodon (29 Apr 2016)

Manufacturers can quote weight with a given frame size. This used to be common.
With different component choices, they could do the same.
That's just my opinion.


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