ESE's works engine tuner

[wobbly]

What you describe is exactly how KZ2 kart engines are laid out.
By reversing the crank rotation in this configuration you will get more power - been there tested that by Mr Thiel.
But to use this layout for a twin in a bike you will need to have an extra gearset, usually arranged as the balance shaft ( KTM250 GP)
between the crank and clutch - goodbye to more than the extra power from crank rotation.

[F5 Dave]

For sure if you are allowed to wc the bike this will make a big step in power consistency and even outright power. Ugly still works. This is my Ally barrel (ignore the torque plates) but I've seen iron ones done. I use a yacht galley pump at present which is absolutely feeble but is so much better than nothing it will stay till other projects are worked on first.

[peewee]

What you describe is exactly how KZ2 kart engines are laid out.
By reversing the crank rotation in this configuration you will get more power - been there tested that by Mr Thiel.
But to use this layout for a twin in a bike you will need to have an extra gearset, usually arranged as the balance shaft ( KTM250 GP)
between the crank and clutch - goodbye to more than the extra power from crank rotation.

so go with a forward spinning crankshaft is what your saying

i got the idea after looking more at the banshee. why not make some new rearranged cases and use proper cylinders. to hell with them straight up cramped transfers

[speedpro]

I watercooled my AC50 cast iron cylinder a long time ago. After I removed all the fins except the very top one it was machined round and then extended by sitting it upside down on fire bricks and building up the top with braze. This was than machined down to match the diameter of the base and a suitable piece of tube brazed on. I had a small radiator made from a piece of Ford TX5 radiator. I had to fully tape it up front and back in the wet to try and get it to warmup. My old sidecar was bought with a watercooled cylinder only. When I tried to sort out the tuning it started destroying pistons. I had the head machined down and waterjacketed and the problems went away.

I watercooled the cylinder on my AC50 for the same reasons you describe - keeping the cylinder cool and dimensionally stable. I think this was a mistake. I should have cooled the head if I was only going to do one part, though ideally both. I thought at the time it would be good to leave the head hot so it didn't absorb heat and lose power. There was a lot of other things not right with that motor so it never really became a problem.

All the heat is generated in the head though it makes it's way to other places, mainly the exhaust. The lower part of the cylinder has transfer ducts so the water never gets near the bore. The upper part is clamped to the head so could dissipate heat into the water in the head.

[Drew]

Running the crank backward will loose power in the gears needed to correct the rotation - more I would guess than any created by having
the "correct" flow rotation.
Having the flow running with the flywheel direction of spin is worth power but then so is shielding the intake flow from the wheels
when an "exit slot " is cut to radially direct the little boundary layer movement there is,up under the piston.

Just do what Husaberg (the bike manufacturer) did, turn the motor 180 and flip it upside down. Though, they did it with a four stroke for Christ only knows what reason.

[husaberg]

Just do what Husaberg (the bike manufacturer) did, turn the motor 180 and flip it upside down. Though, they did it with a four stroke for Christ only knows what reason.

Mass centralisation..........The Two stroke doesn't need it though.
I myself install my on own the garage floor, then do nothing with them

[Drew]

Mass centralisation..........The Two stroke doesn't need it though.
I myself install my on own the garage floor, then do nothing with them

Really? Why not just stack the gearbox to get the crank further back?

[seattle smitty]

Dave, you have a really high-volume water jacket there; my notion was to keep the volume small and go for faster-moving water . . .

[husaberg]

Really? Why not just stack the gearbox to get the crank further back?

Plus it looks dambitching...........but that was the reason they gave.........

or was it.

In the following release, Husaberg explains the benefits derived from its new, 2009 engine redesign that lays the cylinder down at a 70 ° angle. Notable among those is the raising, and moving rearward, of the crank rotation to place the principal gyroscopic effect closest to the center of gravity (CG). This should make the bike feel lighter and change direction more easily.
70° CYLINDER ANGLE
A shallow cylinder angle of 70° enables the crankshaft to be repositioned more than 100 mm higher and approx. 160 mm further back, which moves the crankshaft’s rotating masses closer to the motorcycle’s centre of gravity.

In this position, the gyroscopic forces generated by the rotating crankshaft have the lowest possible leverage effect on the bike, which results in exceptionally easy handling for a four-stroke, single-cylinder.

The favourable side-effects of the lifted engine are a reduced overall width and notably improved ground clearance – an enormous advantage in narrow, rocky terrain.

[Grumph]

I still think someone at husaberg was fooling around with photoshop - and thought "why not".....Then went looking for reasons why.

[husaberg]

I still think someone at husaberg was fooling around with photoshop - and thought "why not".....Then went looking for reasons why.

Took the buggars years to get the kick start on the proper side then they go and get rid of it..........

[Bert]

Plus it looks dambitching...........

I still think someone at husaberg was fooling around with photoshop - and thought "why not".....Then went looking for reasons why.

It would be interesting to see the FMEA or stress modelling on the internals esp. The gearbox.

[husaberg]

It would be interesting to see the FMEA or stress modelling on the internals esp. The gearbox.

The gearbox and pretty much all the engine is generic KTM, or to be more precise what KTM sell as KTM which was derived from Husaberg in the first place.........
Those who I know who have one say they feel like a 250 to steer, but I understand they feel "funny" in the air......

[Ocean1]

Those who I know who have one say they feel like a 250 to steer, but I understand they feel "funny" in the air......

These feel like a BMX to steer:

Dunno about the air thing though, I'm not allowed to do that shit.

[Frits Overmars]

...I set up the water inlet(s) so as to flow the coolest water over the exhaust port area FIRST to scrub away steam bubbles.

That is the main reason for keeping the water jacket fairly tight around the cylinder: you want high coolant flow velocities.
Compare a recent watercooled 50 cc cylinder with for example a classic watercooled Kreidler racing kit; you could keep goldfish in those.

Dave, you have a really high-volume water jacket there; my notion was to keep the volume small and go for faster-moving water . . .

Smitty, how did you manage to read my above post before I even posted it?

I still like my idea (pride of authorship?) of welding some fins on the header pipe of the exhaust to add surface area and cool the slug of A/F that is drawn out into the header until it is shoved back into the cylinder with the reflected wave.

Sometimes it pays to mince words, if only to help you paint a clearer picture in your mind of what is actually going on.
You don't cool that slug of fresh mixture in the exhaust duct; you just try to prevent it from heating up even more.

I'm thinking that the header needs this minor amount of cooling, while the rest of the pipe, downstream from the header, should be insulated with a ceramic coating.

Yes.

The large-diameter areas of an expansion chamber are surely where the major heat loss occurs.

No.
In those areas the ratio between cross flow area and pipe wall surface is such that a lesser percentage of the gas even touches the wall. To say it simple: the gas in the middle keeps warm. Also, by the time the gas gets to this large-diameter area, it has expanded a lot, so its density, including its thermal energy density, is lower.
Simple test: Gentlemen, start your engines and keep touching the header, the belly and the end cone. The header wil be the first to hurt your hand, followed by the end cone, and finally the belly.

...a watercoold Stage6 R/T... Super low exhaust duration (167°).

That Stage 6 R/T cylinder was designed by a friend of mine and he deliberately kept that exhaust way too low, because, as he said: "Everybody is going to grind it higher anyway. And this way they will have a decent result and praise our Stage 6-stuff instead of first ruining it and then bad-mouthing it".
Try giving it 194° exhaust timing and report back. Then build a longer pipe (or just put a distance piece between cylinder and pipe), so even with the long exhaust timing the maximum power will be developed below 14.000 rpm, and report back again.