anal I know but I'd quite like to know the weight of my bike, using luggage scales it seems to depend on where you balance the bike from it as to the weight it shows. So where is the most accurate place to weigh it from? Try to get it at the balance point on the toptube?

Can't you just get on the bathroom scales with & without the bike & then subtract one figure from the other?
If you're under 30 you'll need a calculator 😉

It should weigh the same regardless of where the bike is attached – as long as none of it is touching the floor.

It should weigh the same regardless of where the bike is attached – as long as none of it is touching the floor.

You'd think so, but I have the same problem with the fishing scales I use. Even hanging it from under the saddle at different points can give different weights. Cheap scales??

I've tried using bathroom scales in the past and that really depends on how you hold the bike. I found you seem to end up with such a big range depending on how you hold the bike, how far away from you you hold it etc….

Anyway I've got some luggage scales now so I'll compare

And I only need a calculator if I try to work in stones & pounds….stupid system…

And I only need a calculator if I try to work in stones & pounds

a half wit can add & subtract Stones & Pounds 😉

Don't using fishing scales they'll add at least 3 or 4 pounds. Who ever heard of a fisherman who wanted an honest answer to how much his catch weighed.

Is this thread a joke? Like the second poster said using bathroom scales is so much easier – just weigh yourself then weigh yourself holding the bike and subtract. If it doesn't work maybe you need better scales? My wife has Slater scales and they are accurate to 100g and very reliable. Also you need to have the scales on a hard surface for an accurate reading.

With fish scales you need to make sure the bike isn't swinging, which can be a wee bit tricky, but once you do that you should get consistent weights. Unless they're junk of course.

I'm not joking – the scales weigh different if you hold the bike at different places. Just like if you lean forwards or backwards on the scales you get different weights it is the same with the bike. I'm wondering what is the best way to get the weight to act in a parallel plane. I thought a luggage weigher would be better.

Recently I've just been resting the bike upright on it's backwheel on the scales as that appears to be more consistent than me trying to hold the bike close to my centre of balance at the toptube.

dt78 you really are as retarded as me!

I've been using my bathroom scales for luggage and the bike!

been off 200grams max so far lol

racing_ralph – Member
dt78 you really are as retarded as me!

That's a scurrilous accusation!

You could dismantle the bike and put all the bits and frame in a small box which you could hold closer to your body as you stand on the scales. This would be more acurate. If you have a beer belly make sure you tuck that into.

Or you could take box to the post office and send it to yourself, taking a sneaky peek at the scales when they weigh it….. 😉

Why didn't I think of that?! Forum always comes up with the best suggestions.

*goes off to get allen keys….

Or you could take box to the post office and send it to yourself, taking a sneaky peek at the scales when they weigh it…..

All time classic post

Or you could just get yourself some better hanging scales – don't have any problem getting consistent weights with mine.

Er, you really need to be not holding it. The difference you're getting is probably you inputing up and down movements subconsiously as you try and support the weight – this will probably result in less accurate measurements if you hold it away from your body (bigger moment to support so take more effort). Get some luggage scales dangle from something strong (e.g. workstand). Hang bike from scales, wait until they stop swinging and you'll get the same measurement from where ever you hang it from – it's the magic of physics.

you need the bike to be centrally positioned when you stand on the scales. Eat it and then weigh yourself. Poo it all back out and weigh yourself again

Hang bike from scales, wait until they stop swinging and you'll get the same measurement from where ever you hang it from – it's the magic of physics

and with the magic of simple observation I can tell you that's not the case, so I deduce I have crap scales 🙁

Are they hanging scales, or do you put the bike on top? If it's bike on top, the reason it's different is almost certainly because you're supporting the bike. If it's hanging scales, as long as the bike's static and not touching anything the scales can't read anything but the weight, unless they just have a big error factor.

Are they hanging scales, or do you put the bike on top? If it's bike on top, the reason it's different is almost certainly because you're supporting the bike. If it's hanging scales, as long as the bike's static and not touching anything the scales can't read anything but the weight, unless they just have a big error factor.

If you are using something like bathroom scales, your problem is corner loading errors (and it living in an environment that can be cold or hot and humid). You can reduce this by placing on a hard, perfecly level surface and taking a reading, then turning the scales 90 degrees and taking another reading. Repeat 3x and take the average. Even so the error margin on bathroom scales is pretty big and only gets wider the older they are. Mine were ~2lb out when I used "the me and my bike method" and ~1lb out when I rested the back wheel on and just kept it upright (blatently not a linear scale anymore). The actual weight (on E2 class industrial dispensing scales was 14.503Kg (or half an ounce under 32lb for a burlyish hardtail).

hanging scales are funny onions – I don't trust them as a rule, they are very sensitive to both local gravity and the quality of the materials they are made of, although good digital scales reduce these problems as a lot can self calibrate and have less moving bits inside..

Just because a balance says 50lb in 1 ounce measurements, don't think it is accurate to 1 ounce, it'll more likly to have a tolerence of 8 ounces.

Not being funny but what is "local gravity"? If you use scales on mars they'll read different I guess.

hanging scales are funny onions – I don't trust them as a rule, they are very sensitive to both local gravity and the quality of the materials they are made of, although good digital scales reduce these problems as a lot can self calibrate and have less moving bits inside..

Well even the cheapy digital one I got from ebay has effectively no moving parts, using strain gauges instead. Seems accurate enough – I've checked with things I can weigh on a kitchen scale – also gives the same weight as airport check-in scales. I'd not trust a mechanical one though.

very sensitive to both local gravity

😆 Right.

PSA. 7dayshop are doing digital luggage scales for £8.99 this week.

very sensitive to both local gravity

Right.

Yeah, because the earth is one big perfect sphere of a uniform composition.

is this turning into a geophysical argument?

Yeah, because the earth is one big perfect sphere of a uniform composition.

Which makes local gravity vary more than the resolution of a hanging scale? 🙄

Yeah, because the earth is one big perfect sphere of a uniform composition.

Are you seriously suggesting your digital luggage scales can pick up variations in the earths gravitational field? 😆

For one thing how would you know? Presumably any other scales you compared it with at a given location would be equally 'inaccurate'…

op use a peice of string to hang the bike from the scales. the longer the better. as this will allow it to centralise.

if you can put the bike at the bottom of stairs and hang from top.

HTH

For one thing how would you know?

Well it would be fairly easy to check if it really was an issue.

Yeah, because the earth is one big perfect sphere of a uniform composition.

Are you seriously suggesting your digital luggage scales can pick up variations in the earths gravitational field?

For one thing how would you know? Presumably any other scales you compared it with at a given location would be equally 'inaccurate'…

Yes, I'm seriously suggesting it, although the accuracy of the scales would be more of a factor – I admit I'm used to using much more accurate scales than the norm and are more aware of these things. But why do you think decent balances have a self calibrate function? To allow for local temperature and the local gravity.

Decent scales have a self calibrate function to allow for temperature differences, and mechanical effects, not for variations in gravity. You may be referring to the feature on most scales that allow you to dangle a bag from their hook and not have to do any maths in your head by zeroing the scales once the bag is present.

The difference between gravity at the poles and the equator is about 0.2%, which I should think is somewhat smaller than the resolution of your scales. Unless you're weighing your bike at the Institute of Physics.

(Besides the actual mass of the bike would stay constant, only it's weight would be different, so you're kidding yourself anyway)

Local gravity, lol that's brightened up my morning. Although if it's also mobile I guess it explains why I can never get air off jumps.