The following rear tyres, in the stock size of 140/80-17, do not clear the driveshaft housing:

• Avon ST23
• Bridgestone BT17
• Metzeler ME-55A (unless it has the code 69V)

If these are available in a 130/90-17, they'll all clear just fine.

The following 140/80-17 tyres are known to be fine:

• Bridgestone BT45
• Metzeler ME-55A (only the 69V version!)
• Michelin Macadam 50
• Pirelli Match MT08

Another key is that the bike is incredibly hard on rear tyres.  Fronts wear fairly fast, too, but the shaft drive and hard power pulses tear up the rear.  I've had a reliable report of an ME55A lasting a mere 2500 miles!  Most combinations, though, manage around 5-7k from the rear (and about another 2k from an equivalent front).  Only one, the K491, stands out as lasting over 10k miles, although the Avon Roadrunner AM21 gets close to 10k.

There's also the fact that although the bike has cruiser styling and dresser touring ability, it's also at home strafing the twisties.  This puts extra demands on the tyres.  The Avon Roadrunner AM20 front, for example, is a very nice tyre for general riding, but put it to hard use and the outside tread blocks overheat rapidly; this makes it unsuitable for this bike.

The Safe Bet is to fit the OEM Pirellis.  They're decent tyres, perform well, but tend to an uneven wear pattern.  There are better tyres out there for this bike, but these will fit, and they do suit the bike well.

There is no question about what to put on the rear if you're strapped for cash.  The Kenda K657 lasts around 5-6k, and provides good traction in wet or dry, and even wear.  It doesn't have the stick of, say, an ME88 -- you can break it loose under full throttle in the twisties in first gear, but when you do it slides predictably and comfortably.

The front is a question.  I'm not confident enough about the Kenda front in the wet to recommend it, so I'm looking for an alternative here.  Fortunately the Bridgestone BT45 is very reasonably priced, and makes an excellent choice.

Bridgestone's new BT45 is now the undisputed general purpose tyre of choice for the California.  Available with a stock rear that actually fits the bike, it provides good performance in all conditions, wears reasonably well, and is a very good all-around and sport-touring tyre.  The only drawback is that the front tends to uneven wear, but that does not seem to affect its performance.  It is definitely superior to all the other general-purpose and sport-touring pairs, and having a stock size rear makes a big difference at higher lean angles.

This is the only combination which is known to produce anything like high mileage on this bike.  You can probably expect around 12k from the rear, which on a Cali 1100 is absolutely fantastic.  They'll also stand up well to hard riding and long-distance touring work.  The front is a little wide; the MR size is equivalent to a 120, but the tyre does in fact seem to work well in this application; a 100/90-18 is also available if that concerns you.

The Avon Roadrunner AM21 rear also lasts well, but not as long as the Dunlops.  The catch with the Avon is that in sport riding there's a tendency to run off the edge of the tyre profile -- this can be improved by running higher pressure in the rear (like 39 or 40 psi) but not eliminated.

This classic touring combination from Metzeler lives up to its reputation on this bike too.  They last fairly well, about 8-9k from the rear and 10k or so from the front, and wear evenly.  They are superb in the rain, and stick plenty well enough in the dry provided they are warmed up properly.

In general, Sport-Touring tyres work well for sport riding on the Cali 1100.  Although it has a surprising amount of ground clearance, and superb brakes, the bike is long and heavy to be nimble on any tyres.  The choice here is between the classic Dunlop K591 and the Avon Super Venoms, and although either should work very well, and while the Dunlops are much cheaper, I prefer the Avons.

I would *love* to put the California on radials.  I tried a 140/80 Avon ST23 on the rear, both with the Pirelli Match MT09 front and with a 110/80 Avon AV27 front.  In both cases I loved how the bike responded, but severe clearance problems with the second ST23 forced the end of that experiment.  The ME-Z2 should just barely fit, according to Metzeler's maximum width specification, and combining that with a shorter Z1 on the front should work well.  An alternative would be to go with a mixed-construction set -- pair up the Z2 on the rear with, say, the Avon Super Venom on the front; the profiles should work well together.  Note: Some radials cannot be used with a tube; be careful to check this.

I still haven't come to a solid conclusion for this bike, but this is really looking like I might have found the right choice.  It's a stock size combination with excellent traction and decent wear.  The only question in my mind is how much wear, and what happens to the traction at the rear in cold weather and as the tyre reaches the latter part of its life.

On the front, the Super Venom provides superb traction and excellent highway stability, as well as good wet traction and water dispersal.  The profile matches very well with the BT45 on the rear, which also has good traction and is inexpensive too.

For sport-riding, this combination works well too.  You can scrub both ends until the floorboards hit, and the profile inspires confidence.  It's a great combination.

Avon

Bridgestone

Continental

Dunlop

IRC

Kenda

Metzeler

Michelin

Pirelli

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