Question: Why was the biggest two-stroke bike 500cc?

**Ixion** · 17th July 2008, 13:08

Originally Posted by Grub

Ahem ... have you? These bikes were lethal. The frame flexed so much that the geometry of the bike would change several times in a corner. Yes, they were the Falcon GTHO of the bike world ... they killed people. Oh ... and they sounded GREAT!

I owned the 500 Kawasaki, drum brake model, for a while. It spent every evening plotting how to kill me the next day. Fortunately, for me, I got rid of it before it succeeded. Not so fortunately for the subsequent owner. It killed him. I found the remains in a wreckers a year or so later.

In hindsight the handling was probably no worse than most of the big Jap bikes of the time. But the combination of the hinged frame, and a vicious two stroke power band, and non existent suspension (well, what it ahd didn't sdeserve to be called suspension) was bad news for riders accustomed to the much more fogiving Briddish iron.

The brakes were fine, if you weren't racing. Certainly better than the 6 inch cast iron SLS hub ornaments on most bikes.

**Badjelly** · 17th July 2008, 13:21

Originally Posted by Ixion

Not so fortunately for the subsequent owner. It killed him. I found the remains in a wreckers a year or so later.

Jeez, you'd think they'd bury him or cremate him or something!

That's verging on bad taste isn't it?

**Ixion** · 17th July 2008, 13:43

By accounts, by the time the Kockasucky got through with smearing him over the road, there wasn't enough in one piece to do much with.

In fairness, it should be noted that all thius was long before the graduated licence scheme. And the Mach III was very popular with a certain sort of noob as a first bike. (and, almost invariably, last bike also)

**Motu** · 17th July 2008, 18:00

Originally Posted by Mr Merde

So how many of you have ever ridden a bike with large drum brakes?

4 leading shoe brakes had a lot of feel to them.

I've ridden a Benelli 650 with the large Fontana 4 leading shoe front brake....the spokes were only a couple of inches long.It was on,then ON really,really ON! Not very suitable for a road bike.My Water Bus had the 4 leading shoe,which was sorta ok....hard to tell as it was a heavy bike to haul up.

**MVnut** · 17th July 2008, 19:00

Originally Posted by Grub

Ahem ... have you? These bikes were lethal. The frame flexed so much that the geometry of the bike would change several times in a corner. Yes, they were the Falcon GTHO of the bike world ... they killed people. Oh ... and they sounded GREAT!

But you can make frame flex work for you, and get another couple degrees of lean ..........timing is everything (and big cajones helps)

**FilthyLuka** · 17th July 2008, 19:09

I've always wanted to put a H2A engine with a few tweaks into a GSXR750 oil boiler frame and see what happened

**James Deuce** · 17th July 2008, 19:12

Madmax put one in a ZXR750 frame.

http://www.kiwibiker.co.nz/forums/sh...ad.php?t=38837

People have Goldfish memory syndrome on this site. It must be the motorcyclist to head injury ratio.

**FilthyLuka** · 17th July 2008, 19:33

Originally Posted by James Deuce

Madmax put one in a ZXR750 frame.

People have Goldfish memory syndrome on this site. It must be the motorcyclist to head injury ratio.

Thats hardly a 750 oil boiler frame...

Probably considerably heavier than one aswell

**nudedaytona** · 18th July 2008, 09:19

Are they air-cooled? Where's the radiator?

**bungbung** · 18th July 2008, 09:30

Air cooled, no radiator.

The Deltic was 2 stroke too: http://en.wikipedia.org/wiki/Napier_Deltic

**nudedaytona** · 18th July 2008, 09:35

I see so that's what those big fins around the engine are for.

**rok-the-boat** · 20th July 2008, 23:23

I've got a 115hp V4 1800cc two-stroke downstairs - a boat engine. And I have seen a 350hp V8 2 stroke boat engine.

**cold comfort** · 22nd July 2008, 21:04

Originally Posted by ChocolateWheels

Kawasaki 750 triple 'widow maker'.
My old man got to ride one once, scared the shits out of him!
That bike was the fasting thing on the road at the time and had drum brakes front and rear

crap handling too!

Ahh,i remember mine well. Never had the wind put up me so often since. A triumph of hormones over sanity i'd say!

**cs363** · 22nd July 2008, 21:15

Originally Posted by svr

Old Motorscrapers have 2 stroke V12 twin turbo, twin supercharged diesel engines (aboot 12l I think). They don't go that fast but with open pipes make a 500GP bike sound pretty gutless!

Yep....ever seen a Terex or Euclid dump truck? Some of those things use up to V16 two stroke diesels (Detroit Diesel), Cummins also make big 2T diesels.
Some of the biggest 2 strokes are some ship engines....and they ain't small at all!

Not to mention outboard motors if you want to talk big two stroke petrol engines, I think there have also been two stroke aero engines in the past too.

But, back to motorcycles of more recent times I think 750cc was the biggest commercially available 2T engines, though plenty of people have built hybrids - only the other day I was reading an article on a converted Kawasaki H2 750 that had an extra cylinder grafted on for a capacity of 1000cc!