This is a nice quality tire but I think that it's too narrow for anything approaching fast performance riding. I got this to match the D404 130/90 17" rear for the wheel set that I use for commuting on my '07 KLR650. The rear is big and beefy, feels great on the pavement and just barely fits on the bike without rubbing the chain guard. But this narrow front tire just doesn't have the contact patch to give me confidence for spirited street-riding. It looks like it will last forever so I guess I'm stuck with it.
For a long-lasting 21" street tire you would do considerably better with the Metzler ME880, any of the D/S options or even the OEM tire. Or you could change to a different size rim for more options. Although, hopefully, you don't have a 21" front rim to just ride on the pavement. I'm not sure why this tire exists.