Excuse me if this is old news to you guys but this process is new to me and seems to be working well. The original ducktail seat on my K0 has a near perfect base, but the original cover has not fared so well from age and use. The vinyl on the top was hard and flattened, a cross between a drumskin and an ironing board, just begging to split; the pillion section was much better with the pattern still in relief, not flattened.....and I was wondering what if anything could be done about it.
I googled 'To soften vinyl seats' and came up with not a lot except for one suggestion from a classic Volkswagen car forum (They all have vinyl seats) which suggested using a product called 'Skin so soft' made by Avon cosmetics.
Strangely enough I have plenty of this stuff for a totally different reason; it is widely renowned as the best insect repellent you can get anywhere, bar none. They sell this stuff in bulk to scottish farmers to keep the midges at bay and it's even used by soldiers in hot climates.....and as a bonus it smells good and softens your skin at the same time.
Anyways, I had my doubts about what it could do for the parts of my seat cover that had all the flexibility of a vinyl LP but I had nothing to lose. I have been liberally coating the entire seat and in particular the affected areas for about four days now.....and, amazingly it's working!
Patience is very necessary, I've had to really kneed and work the worst affected areas, and a couple of times left it out in the midday sun for about ten minutes to warm it up and then work the stuff in again.
I wish I'd taken before and after photos as it's way better than when I started; most of the squares on the forward section of the seat which were rock hard and board flat are now flexible and regaining their 'cushioned' appearance, and it feels safe to sit on again without splitting it.
Hope this might help someone with a similar problem...........Mick..................kettle738