Z900?

 

Cylinder head is reversed

I'm going for mid 80's Suzuki GSX1100 with second option Kawasaki

Cheers, SB

 

Yes, I had spotted that thank you Sebastion.

I was looking at that RHS shot. The Z1/KZ has that very large clutch housing vs crank end ratio. Could be a mid 80's Suzuki though as you suggest. I was out of the loop for a couple of decades (but not so long that I forgot what the conventional arrangement for cylinder heads is).

 

Kiwi - you're right. It's a KZ. It's a KZ1000 with a big jug adapter kit to make it's displacement 1400 (you can't bore the oem jugs out that far). But yeah, the reason I posted it was the reversed head. I've seen it done before before. It's another cool thing about air-cooled bikes.


I have a KZ1000 in the garage right now. It's a fun bike. But, good lord, it's HUUGGEEE...

 

What's the point of reversing the head, does it have any power benefit since that bike at least looks to be a drag racer or is it one of those "because I can and don't have anything else to do" things?

 

More direct, cleaner, and cooler air flow. Conventional heads are pumping air against the "natural" direction of flow. So especially on older carb'ed bikes, they saw benefits, albeit small benefits. If you're building an engine and motorcycle from the ground up and all you have to do is flip the pistons, and then flip the head - there's not all that much work involved.

Yamaha dirt bikes use reverse head designs. From a design standpoint, it does make more sense.


Edit: Here's a pic of it on a Yamaha

 

I used to be able to say that too.

When I was 18; now I'm 53, wish I still had one sitting in the garage now.

Exceptional example of a slipper piston in that giant Yamaha photo Conrice.

How does something so small and beautiful stand up to the rigors of living inside such a harsh environment?

But I guess it is a very good example of the ultimate design process; at the end of the day the piston only exists to handle combustion pressures and provide a secure place for the piston rings to live in. That is a wonderful example of form following function.

 

I actually bought it for my father-in-law. He had one back in the 80's and still kicks himself for selling it. It's the one motorcycle he always brings up. So we found one that needed new brakes and some carb work, and my wife and I are going to surprise him with it in a few weeks. I've ridden it around the block (no brakes - clogged idle jets), and I can definitely see what the appeal is. It's a great engine.

 

Do post his face when you give it to him, gonna be one happy pappy!

 

Two strokes don't care. How do you time the cams on a four stroke? The crank sprocket turns them in a certain direction. I guess you'd have to flip one cam 180 for it to work....maybe.