Rode the SDW in a day back in August 97 in 35c then July 98, and it’s a big day out with the longest toughest climbs near the end riding W to E. Mentally found it very tedious after around 50 miles, and then just wanted it to finish but kept on slogging away and made it.
Can’t even contemplate getting there, turning round, and going back!?!?
But what an achievement to even turn up on the day, get to the end, and try to give the double a go. Boy, I wouldn’t want to try and give up half way. Something even harder to contemplate.
And it’s a lot of climbing. It’s around 4500m in 100miles I think, one way. So double that…and you’ve got a oodles. But if there’s no time deadline, and you’re setting yourself a big goal, then get stuck in, prepare for it, and when you dig deep you’ll see that you can surprise yourself.
I was at the Builth Wells marathon the other weekend, and the conditions were incredible. Probably very much like the SDW in summer. And the maths for the climbing vs. total distance on the SDW Double looks like the SDW comes out around the same per mile as the BW marathon.
So plenty of climbing on long rides like you say in your preparation should help.
Very best of luck for September.