Suspension for rider weight - How accurate?

[AdamEf]

Wondering if any suspension gurus out there could give me an insight as to how accurate you need to be with rider weight for rear suspension. Specifically, would it be bad to get a second hand rear shock that's sprung for an 80kg rider if I weigh 75kg? I do usually have a 2kg hefty D-lock under the seat anyway and a few other bits in a bag on the pillion seat which maybe adds another 1 kg. So nearer the suggested weight for the spring with that taken into account.
Seller says there's some leeway with settings.
Am I overthinking it or worrying too much about a few kgs that won't actually make a difference?
Any advice appreciated.

[jaffa90]

What bike what shock??

[mentalboy]

Is it not adjustable?
Setting up for weight is not something I'm familiar with. Every rider has a different riding style, some prefer a soft ride, me, I used to set the shock and forks for a real stiff ride, my mate hated it on the rare ocacasions he rode my machines.

If, for example, you weighed the same as Rossi and had him set up your machine, the likelihood is that you might not like the results, we aren't talking about setting a machine up for carrying a bag of spuds!
Experimentation is the only way you will find out what suits you best.
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Make mine a Corona.

[Old Git Racing]

Should be ok if its for a 80kg rider, you wont be far off that with all your gear on.
What determines whether a spring is right for a riders weight is if you can get the required sag within the preload adjustment available.
For example, if you want 30mm of sag but even with the spring backed fully off you cant get it then you need a lighter spring, conversely with the spring wound fully down if there is too much sag you need to go heavier.
Having this set up correctly makes a massive difference. Most bikes rear suspension is a crude compromise where the shock has to work for all rider weights, carrying passengers etc and is usually oversprung to the point where the compression and rebound are overcome by the spring whereas in an ideal set up the spring is just there to give ride height and return the shock after compression.

OGR.
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2022 Tiger Sport 660 2019 Street Twin 2003 K3 gixxer 1000 1998 Srad 600 track hack

[Hong Kong Phooey]

Fuel tank empty to full would be 16Kg difference right there. I'd not worry about it being bang on a number, so long as it's in the general area, unless you're planning on competition racing.

If it's adjustable then you're going to have to dial it in anyhow.
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'81 CG125, '97 FZS600 : '99 CBR600F4, '09 KTM RC8

[AdamEf]

Cheers guys.

The spring is for an 80kg rider without kit, but guessing it should be failry near. Not sure if it's set up for that weight with track or road riding in mind though. If road I'm sure it'll be fine. track may be a bit of a stronger spring?