Mick:

I had the full kit with the YDS1, it came with two sets of cylinders, pistons, and heads. You changed the cylinders for port timing, the pistons and heads gave you four different compression ratios, all to set it up for a particular track.

"Reasonably fast" means it was a competitive machine at the time, ir you had a big enough set to run it at its limits it would do the job.

But I still didn't like it.

120-130 through the uphill turn at the Glen was a lot more fun.

Bill.