ESE's works engine tuner

[jamathi]

Rod through gearbox mainshaft pushes a piece out to lock a gear to the shaft. If it's a cross or cruciform shaped piece that's where the name comes from.

If it's a simple bar or a triangle shape you can call it something else. Maker's call. Similar box on early Lotus F1 cars was known as the queerbox. As previously discussed here.

I used this very successfully for many years: Jamathi, Piovaticci, Bultaco...

[Grumph]

I used this very successfully for many years: Jamathi, Piovaticci, Bultaco...

Well aware of this sir. Your development and use was argued very well by Frits when it was discussed on here several years back.

[Peljhan]

The same design as Tomos is using it.
If my memory is not at fault, one guy told me, patent was bought from Norton. In a time two companies cooperated.

Jan, I have a question for you. I read your book and at page 78 and 95, you are talking about repositioning primary gears from between cranks to side drive on a Bultaco 125cc 2c.
I wonder why is power gain so large? From 37 to 43hp you gained 6hp, that is 16% increase.
Thank you for answer.

The book was really nice reading I enjoyed. Thanks for taking your time to write it

[yatasaki]

My guess is two bearings less?

[Peljhan]

My guess is two bearings less?

My guess is one shaft, 2 bearings, one gear pair and maybe gears digging/splashing the oil. But 16% looks quite high number to me as gear pair loss is usually 1-3% of power. That's why I ask.

[jamathi]

The same design as Tomos is using it.
If my memory is not at fault, one guy told me, patent was bought from Norton. In a time two companies cooperated.

Jan, I have a question for you. I read your book and at page 78 and 95, you are talking about repositioning primary gears from between cranks to side drive on a Bultaco 125cc 2c.
I wonder why is power gain so large? From 37 to 43hp you gained 6hp, that is 16% increase.
Thank you for answer.

The book was really nice reading I enjoyed. Thanks for taking your time to write it

It was because the middle primary drive made an extra drive shaft necessary.
Eliminating this with the side primary drive also reversed crankshaft rotation.
I was amazed at the improvement!
All other 125's had side primary drive, so we followed!
My mistake was copying the Japanese engines which all had primary drive from the middle.....

[jamathi]

The same design as Tomos is using it.
If my memory is not at fault, one guy told me, patent was bought from Norton. In a time two companies cooperated.

Jan, I have a question for you. I read your book and at page 78 and 95, you are talking about repositioning primary gears from between cranks to side drive on a Bultaco 125cc 2c.
I wonder why is power gain so large? From 37 to 43hp you gained 6hp, that is 16% increase.
Thank you for answer.

The book was really nice reading I enjoyed. Thanks for taking your time to write it :nice one:

My problem was that I followed Japanese practice of putting primary drive in the middle, which causes a big power loss.
Where this came from I don't know, probably MZ-Degner...
Jorg Moller discovered this when helping Jos Schurgers to build the Bridgestone 125-2
Using Bridgestone crankcases, they were practically 'obliged' to use side primary drive
And discovered that it went very well!!
So when Moller went to Morbidelli he made an engine with a side primary drive
It was a BIG success!
And I made a BIG MISTAKE, which cost me power for years to come.....

The book was written by an Italian, it brought me a lot of satisfaction, we did it together using 'SKYPE!
And it saved my life, because with the earnings we could pay a recent hospital bill.
Without it I would be dead now..........
I am very grateful to my friend Dolph van der Woude who distributes the books!!!!!!!!

[aljaxon]

...the nozzle with diverging cone at the stinger entry has been superseded by a short section with a step - more power.
.

are there any diagrams of this anywhere please? ive searched this thread for stepped stinger entry to no avail

apart from this reply you made ..

"and , not having a slow taper exiting from a stinger insert.
This should have a 45* step , and reduces the effect of the waves bouncing up and down the stinger , from the atmospheric end ( the muffler entry in the case of a KZ ).
These can interfere with the main positive reflection off the reverse cone , as the + wave bouncing off the open ended pipe reverses sign and travels back to the stinger entry."

but im struggling to visualise that.

[Peljhan]

Me and friends bought about 10 books combined. I am happy that it helped you as you helped us with 2t tips and tricks. Stay healthy!

[porttiming124]

Jan, are there any English version books left?

[koenich]

Jan, are there any English version books left?

jep, I just ordered one

[wobbly]

Al , the sketch I did of the KZ stinger tells you everything.

[aljaxon]

Al , the sketch I did of the KZ stinger tells you everything.

i saw that a week ago but didnt realise that was the stinger diagram.

i cannot fathom it out sorry.

sorry to be a pain.

[wobbly]

What is there to figure out - the stinger is a tube approx 3mm bigger ID than a nozzle insert that is up against the rear cone exit.
There is a small taper on the insert entry to match the rear cone exit ID .
The original insert was a tophat to locate it in the end of the tube , and the stinger tube fits into a short female spigot welded to the end of the rear cone.
But the tophat , with the taper inside , in actual fact made the rear cone longer, so I cut it off.

In the KZ I cut the stinger short so that the insert would push in , up to where the bend started , so it would not go in any further.
And instead of a long slow divergent exit on the insert , I cut it to form a 45* step.
The step has virtually no effect on the outgoing wave , but reduces the amplitude of the return wave bouncing back off the stinger exit.

The small nozzle , large stinger idea was invented by Helmut Fath for Fast Freddies first NSR250GP Vee Twin , that had one stinger 150 long and one 450 long.
That small , short nozzle basically all but eliminated the tune difference between the two pipes on the Honda.

[Frits Overmars]

Jan Thiel was urgently admitted to hospital two weeks ago. Three stents have been placed in his heart. He is now back home but it cost him a lot of money;
healthcare in Thailand cannot be compared to what we know here. That is why a campaign has been started to support him financially.

https://www.gofundme.com/f/can-you-h...ource=facebook