ESE's works engine tuner

[lodgernz]

Here's a good place to monitor weather where you'll be racing
https://airdensityonline.com/tracks/

Thanks, that's useful for the big tracks, but only includes one kart track.
In any case, the air density varies all the time, so using an average value would be less useful.

[wobbly]

Ive been to every kart track in the country and the only one that has any issues getting current cell phone based weather data from a nearby airport is Rotorua.
Only due to being in the middle of nowhere .
But even there its possible to travel not far to get a signal.
The same app works in Vegas , Lonato or Te Puke.

[Muhr]

Yes you understood me.

For the gears, the language barrier will make this impossible

I invite you to try the "filengrenne" software which I think will give you a little answer for gears.

https://moodle.insa-rouen.fr/course/view.php?id=700

Looks really interesting! Have only seen a few videos with very limited understanding of French, but will try the program as soon as I get to a windows computer.
looks like it has a cam module?

[philou]

The software manages all common involute gears types of metric module and diametral pitch toothing.
They manage gears interference, teeth creeping,...

It's free. Only the post-processor and gcode function to codrive the cnc machines can be purchased

The export in CAD software is ok and free.

Warning to the units metric and impérials set between in the software

[Vannik]

Gasdynamics - Issue 2

Please let me know if you disagree, want something explained better etc.

[41juergen]

Neels, is that correct or is the bulk temp lower because of the short circuting?

The effect on the pipe, other than the pulse shape change by the contact discontinuity, is that
on the older engine the pipe bulk temperature is higher than on a modern engine and the
result is a longer tuned length for the same rpm value

[Frits Overmars]

Gasdynamics - Issue 2. Please let me know if you disagree, want something explained better etc.

Once again great reading Neels. To come across something described so clearly and understandably is a rarity. It reminds me of professor Alfred Jante's treatises that I cherish .

[dutchpower]

I like only the last line Frits and Neels

. This promotes mixing of the gas and it smears the contact discontinuity. So if your
pipe relies on the primary or secondary contact discontinuity, having a bend in the header will
influence the way the pipe works. This is why some pipes are sensitive to curvature and others
not.

[Condyn]

Neels, I just want to add to the praise. To elegantly answer that many gray areas in my, and many others thoughts takes a great deal of skill. The FOS pipes I showed a few days ago that worked very well were originally built for, and tested on a vintage machine with the same “port map” on paper as the more modern machine that they did very well on. They did absolutely nothing for the vintage shaft duct, blowdown deficient engine. I somewhat expected that result from bits I have picked up on to do with diffuser design, but this really helped. Thank you very much.

[Vannik]

Neels, is that correct or is the bulk temp lower because of the short circuiting?

The effect on the pipe, other than the pulse shape change by the contact discontinuity, is that
on the older engine the pipe bulk temperature is higher than on a modern engine and the
result is a longer tuned length for the same rpm value

Yes, the short circuiting is less than the residual fresh charge in a modern engine, plus a modern engine has a cooled exhaust port duct.

The aim on a modern engine is to plug back into the cylinder only the coldest and purest part of the fresh charge in the exhaust port duct. That way we can prevent detonation and gain power.

[Condyn]

Shown is a sketch of something that I have been wondering about. The numbers are fabricated, more so the idea that is of question. A 1mm oversize piston and cylinder coupled with the engines factory 1mm smaller cylinder head, whilst using a L-ring piston. The squish gap is large at 1.6mm, just an everyday rider engine on pump gas. Being that it is an L-ring, is it still necessary to cut the head to the proper bore size, or would it be more logical to leave the smaller head diameter because the ring is a few degrees lower than the edge of the piston? I understand the nooks and crannies are of concern, but what is worse? You either end up with corners, or a larger gap between the ring and the “new” cut head. If I smash solder with the smaller diameter head it measures 1.6mm inside the squish band area and 2mm above the ring. If I were to cut the heads, there would be an even larger gap above the ring.

1mm larger diameter is .5mm per side. ( obviously but worth noting )
Apologies for the likely sideways photo.

[wobbly]

Having alot of mixture trapped at the bore edge is asking for deto as there is no cool surface close by , plus that volume burns way too late in the combustion cycle to help push the piston down effectively.

[Muhr]

The software manages all common involute gears types of metric module and diametral pitch toothing.
They manage gears interference, teeth creeping,...

It's free. Only the post-processor and gcode function to codrive the cnc machines can be purchased

The export in CAD software is ok and free.

Warning to the units metric and impérials set between in the software

I took the easy way this time but a super usable program that I will benefit from many times!

[Frits Overmars]

Muhr, setting the correct clearance on a set of such gears is a nightmare. You should definitely google Cylkro Kronenräder. It offers a much better solution. If I had encountered it earlier, I would undoubtedly have recommended it for the Aprilia RSA.

[philou]

The engineers blue marking is very good for locating the surfaces of the gear teeth and adjust the correct clearance

Old school style