The ME-Z4's are excellent tyres indeed, and well suited to this bike.  I just can't argue with Suzuki on this one.  Good wet and dry traction, good wear, a stable neutral linear profile, all these qualities match well with the handling characteristics of the SV.

Now for a lower cost, the recent price decrease of Dunlops makes them a shoe-in for this selection.  While not exactly cheap, they're the cheapest available, and are certainly good tyres.

For sport-riding on a bike like this, there is an overwhelming selection of good tyres.  Avon's Azaro (with an Azaro or AV27 front), Bridgestone's BT56SS, Dunlop's D207 Sportmax, Metzeler's ME-Z3, and Michelin's HiSport TX15/25.  Which one you choose is basically a matter for your preference.

If you like the profile of the stock Metzeler ME-Z4, you'll love the ME-Z3.  The main characteristic of the Z4 and Z3 series is their absolutely neutral profile, which many riders like.  Personally I find them a little too neutral for sport-riding.

The Dunlops are the other extreme.  A non-linear profile that tends to drop into the turn more as you lean more, it's not confidence-inspiring and I find it unpleasant.

The Michelin HiSports are just way too expensive to consider.  They're a great tyre, but the price is outrageous.

At the other end of the price scale comes the Bridgestone BT56SS, perhaps the best tyre Bridgestone makes.  It's relatively inexpensive, and performs well.

And then there's the Avons.  The Azaro AV36 rear is amazing on a bike with a lot of power out of the corner, like the SV650.  The variable belt density construction seems to squat down onto the contact patch as you gas it while leaned over, and gives a very confident feel that helps you get on the power early.  It's an excellent match to the bike.  The front Azaro AV35, however, has a bad tendency to uneven wear -- while it sticks well, it doesn't last.  The solution to that is to put on Avon's AV27 front.  This has a less marketing-derived tread pattern, and in fact the Azaro rear was originally designed to match the AV27.  The AV27 doesn't share the VBD construction and has a more conventional tread pattern, and wears well -- and the kicker is that it's a perfect match for the Azaro AV36 rear, sticks well, and has excellent highway stability.  In my opinion you can't beat this combination on the street.

I've described this combination above under Sport-Riding: it's a superb combination for the SV.  Now if you aren't going to be doing any sport-riding, I'd recommend the Safe Bet Metzeler ME-Z4's, but the Avons are what I'd put on the SV.

Avon

Bridgestone

Continental

Dunlop

IRC

Metzeler

Michelin

Pirelli

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