No, I initially thought that. However, OTR categorically stated that it did not have a spring to suit the YA817 to specifically suit my weight. It might be that the number I gave them confused the issue, but maybe they should have known enough to offer the 90nm spring as shown by minkyhead.

The 115nm spring offered by them is almost 50% stronger than the standard 80nm. Clearly this is excessive, as correct static sag can be achieved with the 80 if it's screwed down hard enough. However, as minkyhead stated, that makes the ride harsh. Better to get a spring a bit heavier, and get both static sag and ride height right imo. This improves ride quality.

Thanks for you thoughts though, Marcus.