Beamish wrote:Just give me the word and I will tee him up. I have to pre order the 190's as a lot of the teams use a 180 for quicker turn in. Top bloke and he knows his tyres. I paid him £90 for the pair yesterday as he came out especially on a Sun

I was speaking to Bryn Phillips at a recent track day, and yes he was selling me some Dunlops (he works for them), but I think he knows a few thinigs about tyres.
I was primarily buying some tyres for my Firestorm track bike, recently used Racetecs, K1 both front and rear. No complaints. But dunlops were on offer so I got some. Anyway, that's the history.
I asked him about my SP2 and the rear 190 tyre and asked if I could get some 180s to put on. He said that this was a hang over from the 90s where they used to do this to improve turn in speed. He now says that it's bad practice since the tyre profile changes dramatically when you put them on the wrong wheel. Imagine when if you put a 180 on a 190 tyre, it will stretch the tyre width ways. This results in the profile becoming more flat. Turning in would be faster, only when you meet the shoulder! It's the same principle as riding on a squared off tyre

, which is not a happy experience.
I've never ridden on 180 tyres on a 190 wheel, but it makes sense to me.
I've just changed my new BT-021 (on the bike when I bought it) with Dunlop Sportmax Qualifier II, IIRC. I thought the BT021s turned in too slowly. I'll be intersted to see tomorrow when I try it out.
No bike (yet).