Valve sizes...

[fintip]

Not the shims, the valves.

On fjmods.co.uk, I found this:

I do still have one FJ (the one with the white wheels), and Jerry Berreth has just completed a cylinder head for it.  He put 30.5mm intakes and 26mm exhaust valves in it (up from 29/25 stock) and it flows over 130 cfm (stock is only 90-92cfm) at 10" of water.  That puts this head in the realm of a Hayabusa!!  Interestingly enough, the Busa's bore/stroke dimensions are 81/63mm, and the FJ1314 is 81/63.8mm - almost identical.  I'm attaching some pics so you can see the handywork.  Lighting was tough but I did my best.

Sounds cool.

Later in the day, I read a bit more about the FJ600. I noticed this, on the review featured here:

As a look-alike little brother to the FJ1100, the FJ600 promises true sporting performance. Though a few engine parts were borrowed from previous machines, the FJ600 is essentially all new and aimed squarely at sports riders. The 16-valve engine features valve sizes normally reserved for 750s: 31.5mm intake, 27mm exhaust and the four carbs boast large 32mm Venturis.

Am I to understand the the FJ600 had larger intake and exhaust valves than the FJ1200?

And if so, what am I missing that makes that not make sense? Does that mean there's a beast in the FJ600 waiting to be awakened by an open exhaust and intake + carb setup?

And before someone asks, yes, the 600 featured a 16 valve arrangement.

[oldktmdude]

   The valves may have been larger but there were only half as many. Eight valve engine not sixteen as stated.   

[fintip]

Interesting! Is the review wrong? That would explain it. That would make perfect sense. Don't know why I didn't think of that.

I found this website: http://www.motorcycle8.info/moto/Yamaha/yamaha-fj-600.html

Which copied the same review, but in the 'data' section shows it as being two valves per cylinder.

Mystery solved.