ESE's works engine tuner

[2T Institute]

Attachment 257559 Attachment 257560 Attachment 257581

30mm at the engine end and 24mm at the bellmouth. The std 24mm OKO is bored 24mm parallel straight through, so I taper bored it and left just a 2mm length of the original 24mm bore in the bellmouth. The first part from the bellmouth to the slide is a little steeper than from the slide back to the manifold. The last 45mm is the manifold and rotary valve cover.

I suppose it's a bit late now but I like to leave 10mm at the back(engine side ) of the slide parralel also. Though I'll be interested to see if what you have done works alright.

[Frits Overmars]

water has to have sufficient time to absorb the heat that we are asking the water to carry away from the motor. If water flows to fast and there is little heat transfer we may overheat a motor. If there the water flow is overly efficient and carries away to much heat we face a different issue of getting incomplete combustion and the motor running poorly

Compare two cooling systems, A and B. In system B the water flows three times as fast and picks up only half the amount of heat per liter, compared to system A.
Then system B removes 50% more heat than system A! And provided your piston clearance is OK, you just cannot have too much cooling. In the Aprilia RSA125 the water pump circulates 160 liter per minute. That is 3 liter per HP per minute!

The thermostat and all of its parts are anodized to protect it from the corrosive nature of many of the water and water treatment chemicals used like water wetter.

Nowadays we have a fine solution for avoiding corrosion; it's called plastic. Saves weight too.

PS $200 dollars buys a lot of tape

I don't know exactly how the NZ dollar is doing, but that sum will probably buy you two of these:
http://www.hvg-engineering.com/index...id=127&lang=NL

[teriks]

BS. Compare two cooling systems, A and B. In system B the water flows three times as fast and picks up only half the amount of heat per liter, compared to system A. Then system B removes 50% more heat than system A! And provided your piston clearance is OK, you just cannot have too much cooling. In the Aprilia RSA125 the water pump circulates 160 liter per minute. That is 3 liter per HP per minute!

That's plenty of flow, how much power does the pump absorb?

[TZ350]

I suppose it's a bit late now but I like to leave 10mm at the back(engine side ) of the slide parralel also. Though I'll be interested to see if what you have done works alright.

10mm parralel behind the slide also, is more or less the configuration of the carb Chambers prepaired for Av's bike and it runs fine. My tapered right through idea works on the dyno but has yet to be tried on the track, fingers crossed it works OK but I will be taking a spare carb with us to Te Puke just in case .....

[wobbly]

I have had a bunch of those thermostats made - as the Guhl price is burglary, you can have one for 150nzd delivered..
They dont "fix" a deficient cooling circuit - just regulate the temp as seen at the engine to a constant 50C, as long as the rad and pump can cool the water
to that level.
Perfect if the rad is too big, it delivers the same temp all the time with no tape needed.

[bucketracer]

Water Cooling! ... did anyone notice that 2-stroke at Tokoroa that ran strong all day and sounded crisp start to finish, winning every race and in the 30 lapper laped every other bike, taking them two and three at a time down the straights was ... Air-Cooled!!

[wobbly]

Bottom line is that if one were to put in 1/2 the effort and time that has been put in on that engine, but started with a modern watercooled top end,fitted a Wobblypipe of course - and
stuck Av on that, she would have smoked/lapped herself.
Remember - it was only a few years ago that I was laughed at for suggesting 30Hp from a 100 was easy if it was done right - now we have a 125 Aircooled doing it.
Its all relative.

[TZ350]

Bottom line is that if one were to put in 1/2 the effort and time that has been put in on that engine, but started with a modern watercooled top end fitted and a Wobblypipe of course .....

They have the same power but, the I00cc water cooled with Wobbly pipe, red line, has a much better spread of power compaired to my 125cc air cooled engine, blue line, dam good results from a 100.

[crazy man]

They have the same power but, the I00cc water cooled with Wobbly pipe, red line, has a much better spread of power compaired to my 125cc air cooled engine, blue line, dam good results from a 100.

the big thing is will it last a GP? all will the tractors take it again?

[cotswold]

Water Cooling! ... did anyone notice that 2-stroke at Tokoroa that ran strong all day and sounded crisp start to finish, winning every race and in the 30 lapper laped every other bike, taking them two and three at a time down the straights was ... Air-Cooled!!

Oooh I spotted that !! Water cooled buckets who needs one?

[Farmaken]

the big thing is will it last a GP? all will the tractors take it again?

2012 .... Year of the Dragon. I mean two stroke !! Bring on the GP

[bucketracer]

- it was only a few years ago that I was laughed at for suggesting 30Hp from a 100 was easy if it was done right - now we have a 125 Aircooled doing it....

High hp air cool ed's have been around for a while ........ 28 hp claimed by SS90 ...... posted March 09

I have ALOT of experience with this subject matter, and am willing to pass it on to..... "the boys back home"

Man, you guys are way behind....

Oh, yea, 28 P.S .....is the most I have ever seen out of an....AIR COOLED, DISC VALVED 125cc TWO STROKE.... Oh, the 28 P.S is with my own exhaust as well.....

I know alot about "DISC VALVED, 130CC TWO STROKES RUNNNING 24MM CARBS…

And..... The Primary compression ratio is 1.49:1

I have loads of dyno runs experimenting with primary compression ratios......

1.5:1 is always the best curve (long and fat)....

28 ps (DIN hp) with 20Nm (14.75 ft/lbs) torque and about 2.5K usable power spread.

[husaberg]

Water Cooling! ... did anyone notice that 2-stroke at Tokoroa that ran strong all day and sounded crisp start to finish, winning every race and in the 30 lapper laped every other bike, taking them two and three at a time down the straights was ... Air-Cooled!!

No one has ever accused me of being a Rhodes Scholar. Or is likely too either anytime soon.

But.......
put someone slow on a fast bike they will generally go pretty well still, if not a maybe bit shit on the corners.

Put someone fast on a slow bike they will generally still go pretty fast just a bit shit on the straights.
But they will make up a bit with fast exit speeds and late braking.

Put some fast but pretty heavy on a fast bike they will still do ok.

Put some pretty fast on a fast bike and they will be hard to beat.

Put someone fast and pretty and light on a very fast bike and well nearly unbeatable.
If you then throw in some Handling, Well it could be construed as sexual harassment


Cylinder finning

I was actually looking though a old two wheels the other day and this engine which i remember seeing before caught my attention.
Can't find the mag at the moment and this is the only pic i can find at the moment sorry it is real grainy, but you will get the idea.
I am not sure why the fining is like this if it is a continuation of the strips to stop the fins ringing or partly for strength but it got me thinking.

The old space frame John Player Norton with a fairing had a should around the engine to direct air flow through the fins the fins. Instead of going past or around the engine.

This engine a minerilli I think could do the same it would also give additional fin area easily.

I think planes sometimes have the raised tips on the end of a wing to stop the air spilling over the ends


as do a lot of foils on race cars.

I see also there is many factors to play with if you delve into wing designs with the shape of the individual fins the texture as well as the end shapes and angles of the fins (wings)

I would still, like to see an radial Sunburst or porcupine finning on the head.
Or you could just use liquid cooling but then you will have to lose 25cc or so

Also found this pic of Mr Thiel

[Frits Overmars]

....Also found this pic of Mr Thiel

You want pictures of Jan? Then here are two; one from 1960 (note the riding number...), the other one 50 years later.

[Brian d marge]

Very quickly, with fins , look at the heat path and the materials it crosses, also the air flow between the fins , and the amount of heat each fin can remove,

Heres a paper on fins , hope this helps

Stephen