No But I can vouch for Silkolene. So long as your using a high quality, Ester based synthetic designed for Motorcycles, I think you will be extremely pleased with the results. I know I was...
I use Silkolene Pro-4 Race 10W40. the thing I noticed most was improved tranny feel, and I would swear she felt faster.
So, although I may not have experiance with Repsol, it's supposed to be good stuff, and I am willing to bet it's on par with Silkolene so you should be pleased.
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