# weighing a bike

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I was watching a few guys weighing some dirt bikes they put the front wheel on a scale jotted down the weight and then put the rear of the bike on the scale and added the numbers and claim this is what the bike weighs, I got wondering if this is an accurate number

Chet

no...

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This method will give too low a number.

At the very least, you would have to stack something so the tires where they touch the ground are the same height. If one tire is higher, the tilt moves the c.g. of the bike toward the low one, so the tire that's on the ground carries more than its share of weight as each tire is weighed.

I have access to car corner scales, and just put it on two of them.

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As mentioned, as long as the tire on the ground is sitting on something the same height as the scale to keep the bike level then this is accurate. If the one tire is just sitting on the ground then it will be a little off, though bathroom scales are not very tall to begin with so the error will be pretty small.

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take two bathroom scales and put a 2x4 on top of both. Put the bike on the 2x4, add the two numbers and subtract the weight of the 2x4

Had to weigh a garage door once

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do you have like one of those giant trophy fish scales? like the ones that go waaayy up there... that'd probably work

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take two bathroom scales and put a 2x4 on top of both. Put the bike on the 2x4, add the two numbers and subtract the weight of the 2x4

Had to weigh a garage door once

Or just put one scale under each wheel (assuming the scales are the same height and are both calibrated properly).

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lift your bike on the stand, if your back hurts it's too heavy....

also can someone explain why the get heavier and taller toward the end of the day?

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lift your bike on the stand, if your back hurts it's too heavy....

also can someone explain why the get heavier and taller toward the end of the day?

Pretty sure I'm shrinkin and getting weaker. I just puff up before the ride

Brain seems to be fading too.

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Unless your bathroom scale is 6" tall, the shift in CoG isn't going to even be measurable. It's an order of magnitude greater than the resolution of the scale...

For a rough estimate (~5%) of the weight, slide the scale under each wheel and add the two. (My bike's 272 ready-to-ride)

The guys that go nuts with snowmobiles have a load cell hooked to a scale, then they hang the sled by the bars from that load cell. That'll get you 1-2%.

Really though, I can take a big dump in the morning and change the weight of machine+rider more than the error of the scale. Makes me laugh when I see people spend \$10k on titanium hardware and lightweight-everything on a sled when they could stand to go on a diet and shed more weight off them than they took off the sled.

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Really though, I can take a big dump in the morning and change the weight of machine+rider more than the error of the scale. Makes me laugh when I see people spend \$10k on titanium hardware and lightweight-everything on a sled when they could stand to go on a diet and shed more weight off them than they took off the sled.

The damn truth!

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Used to put a scale under each ski and preload the ski shock springs to equal the ski pressure, but that was on ice. Here in the mts' the skis are just to tug on when your stuck, LOL.

I'm afraid to weigh my bike, don't wanna know, could get expensive.