Rear spring rate

I know this must have been covered before but just looking for some advice.

I've got a GSXR 750 SRAD Ohlins rear shock on my bike and have just had it serviced and replaced the spring with one a bit more in keeping with my weight.

I'm about 15 stone without my kit on so add a stone and a bit for leathers, helmet, boots and back protector and I was recommended a 90 rear spring.

Everything's back together and the rear feels rock solid. If I sit on it nothing moves and if I bounce on it it's mostly the tyre that appears to be moving.

Feels like I've gone too stiff on the spring and will get on the phone tomorrow to see what they say but wondering what thoughts on here might be.

Need to get all the front and rear ride height and sag set up but didn't want to get in the middle of that and still find the spring is too stiff.

i'd do the sag. if you can get it to desired numbers then theoretically the spring
rate is correct.

Cheers for the reply.

Checked front and rear sag tonight and it turns out the rear suspension had bound up when I'd re-fitted it and when my friend was compressing the rear for one of the sag measurements it sprung free (no pun intended).

Got the static sag at about 10mm for a rider sag of 35mm so its about right and will see me right for the start of the season.

Relieved its looking right though as times running out to get anything changed.