General Comments

Of those that are available, the new BT45's from Bridgestone are definitely the best.  A successor to the well-known BT35's, they incorporate a bunch of improvements, most notably a tread compound formulated for better wet traction.  They're dual compound, with a harder-wearing centre tread, and so should are well suited for all sorts of riding.  The BT45's are intended for small- to mid-size motorcycles, and the Seca II is very much in that category.  They're even one of the cheapest selections!

The only drawback is that the front has a tendency to uneven wear and cupping.  Compared with all the other selections, however, they're still the best combination out there for all sorts of riding from commuting to full-out sport riding.

There is just one radial combination available for this bike.  While the AV27 is a very good tyre indeed, the AV281 is designed as a general-purpose sort of tyre, not really what I'd put on a Seca.  While a good choice for touring, most riders would probably do better with one of the bias-ply sets.

For touring riders, however, the comfort benefits of radials, combined with the superb stability of the AV27 front, would tip the balance in favour of this pair.

Assuming, of course, that you can find an AV281, which seems to be hard to get in the USA...

The Seca II is a good all-around bike, and I'd put all-around tyres on it.  The BT45's are excellent all-around tyres, and Bridgestone's "sports mileage" tyres have a very nice profile which contributes to good steering characteristics.

If a better radial rear becomes available, I might change my choice.  Until then, the BT45's are the way to go.

Avon

Bridgestone

Continental

Dunlop

IRC

Metzeler

Michelin

Pirelli

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