ESE's works engine tuner

[eldog]

Just

This word should be removed from anyone who works with machinery

its caused grief every time it’s used.


note: it’s not a comment on what you proposed, only the word.




Alignment for timing seems problematic

[katinas]

Nice engine, nice video. It left me with two questions.
1: Why the threaded plug in the crankcase wall for access to the crankshaft pinch bolt, if that bolt is readily accessible from above?
2: Why are both piston ring slots right above each other instead of spread over the piston circumference? Just because it was convenient to use one long stift, fitted from above, for both ring slots? I will admit it's KISS, but I don't think it's the best way to reduce leakage.
Attachment 346262 Attachment 346261 Attachment 346260

Plug in the crankcase wall, allows to check the tightening of the bolt without removing the cylinder.
In this video is simplified mass production version engine, but before, from 1969 they four years tried prototype engine in the boat race. And it was unique in the Soviet Union that the racing engine was adapted for mass production, always in reverse. Maybe they use only 1 piston ring on first race version, but I dont know.
Add again two schemes with arrows, full engine-is race version, only power part-is mass production.
Race version- rounded intake tunnel, different transfers tunnels shape, plated aluminium cylinders, cdi ignition, carb position on crankcase side, central crankcase part with fully opened tunnels for less weight and maybe for air circulation.
And finally on this engine was used centrifugal water pump, not usual outboard rubber high friction type. And sometimes, air in cooling system, caused exhaust side piston seize.

[katinas]

A
Another option is what Aermacchi HD used.
Attachment 346268Attachment 346269

t

Huge Central clamping flywheel was used on Иж Юпи́тер 350 parallel twin.
There was a race version of this motorcycle Иж Юпитер Ш-11 Ш-12, that was used in soviet championship and technical commission firstly checked (through a window in the crankcase) if the heavy steel flywheel was not replaced with light aluminum. The smartest used titanium, the color is similar to steel and similar for scratching

[katinas]

A
Another option is what Aermacchi HD used.
Attachment 346268Attachment 346269

t

Huge Central clamping flywheel was used on Иж Юпи́тер 350 parallel twin.
There was a race version of this motorcycle Иж Юпитер Ш-11 Ш-12, that was used in soviet championship and technical commission firstly checked (through a small box in the crankcase) if the heavy steel flywheel was not replaced with light aluminum. The smartest used titanium, the color is similar to steel and similar for scratching.
If only small clamping piece like on Aermacchi HD was allowed......

[Ocean1]

Probably thermal fit should work OK.

A self-locking taper (under 3 degrees, inclusive) can take a hell of a lot of torque. Morse tapers support massive loads driving drills.

A sleeve incorporating external seal grooves with an accurately ground internal Morse taper and lightly shrink fitted with a little heat would not move. A key or pin as a backup just reduces the capacity of the taper, introduces stress risers and won't help if the taper does let go.

The only problem I see with the general concept is the lack of a purely mechanical axial location and the requirement to time the cranks at assembly. So maybe you'd need to either use open roller bearings or a floating fit. And you'd have to make an assembly clamp/jig to hold the cranks halves correctly timed and apply the right force after the sleeve is warmed up.

Edit: you'd also have to make provision for a grease port at the center of the sleeve, for disassembly.

[WilDun]

In my experience the conical (tapered ) shaft arrangement as in the Ariel Arrow was not really satisfactory, as a key will move if the taper is not holding 100%!

Perhaps nowadays that isn't important I dunno, but way back then, when trying to race the thing, the ignition timing for both cylinders was taken from one crankshaft and caused constant headaches.

So (in hindsight), the timing constantly altering and causing big problems suggests that things were moving! - that can only get worse! The cranks (being pulled together by a central bolt) would then depend on that bolt and the key only ...... a key would not be adequate to keep things accurate and stood no chance of holding it alone!

J B - All this may not be relevant in your case of course (with less acceleration and deceleration) but thought that in the interest of safety in the air, I should point out the possibility of things failing!

....... only my opinion of course, but I would go for a spline first, or maybe a Hirth coupling! - then, the costing of it all has to be considered I guess!

[Muciek]

https://www.jordan-anwar.com/product...king-assembly/ maybe look for something like this and cut lab rings on the outside (or press a liner with them) ? They are used in CNC machines so they can't slip , there is also a version that looks like ER collet but can't find it online now.

[wobbly]

JB the central sleeve idea is for sure the KISS solution, but would also need the inner wheels/stub to be hollow to enable the sleeve ( with a thin solid center section ) to be pressed off easily.
If the sleeve was thick enough then small woodruff keys could be used for axial positioning at 180*, but as you will be doing a few then building a die set with setup holes to locate on the opposing
crank pins is an easy solution - this is how I do many RD/TZ/LC twin cranks , and then press on the outer wheels last.

[ken seeber]

EXHAUST AIR INLET

The idea is to fit a reed valve(s) into the inside of the exhaust cylinder passage or header or divergent cone. The reed valve being arranged such that it could admit & cool fresh air into the exhaust system. The reed valve being opened & closed by the cyclic pressure pulses in the system. When there is a negative wave adjacent to the valve, it could open and admit fresh air into the exhaust.



This fresh cool air could possible displace some of the charge from the cylinder that passes into the exhaust prior to being plugged back. Potential benefit being that there could be a cooler charge in the cylinder at the time of EPC. Cooler = greater mass = more power.

Usual practical issues: mixture control, durability, noise, fitment etc.

So, if you think it is a dumb idea etc, then I’ll just say it was a friend’s idea.

[husaberg]

JB the central sleeve idea is for sure the KISS solution, but would also need the inner wheels/stub to be hollow to enable the sleeve ( with a thin solid center section ) to be pressed off easily.
If the sleeve was thick enough then small woodruff keys could be used for axial positioning at 180*, but as you will be doing a few then building a die set with setup holes to locate on the opposing
crank pins is an easy solution - this is how I do many RD/TZ/LC twin cranks , and then press on the outer wheels last.

Its not the world's best example but the TZ750 only uses a separate keyed gear doesn't it.
i have never seen on but i assume its a taper fit. but it has a bolt on much like a shitty old pommy cranknut.
pretty sure it gave trouble back in the day, i remember reading something about it from Cameron


The NSR500 uses similar
but i suspect it used splineed shafts

---

EXHAUST AIR INLET

The idea is to fit a reed valve(s) into the inside of the exhaust cylinder passage or header or divergent cone. The reed valve being arranged such that it could admit & cool fresh air into the exhaust system. The reed valve being opened & closed by the cyclic pressure pulses in the system. When there is a negative wave adjacent to the valve, it could open and admit fresh air into the exhaust.



This fresh cool air could possible displace some of the charge from the cylinder that passes into the exhaust prior to being plugged back. Potential benefit being that there could be a cooler charge in the cylinder at the time of EPC. Cooler = greater mass = more power.

Usual practical issues: mixture control, durability, noise, fitment etc.

So, if you think it is a dumb idea etc, then I’ll just say it was a friend’s idea.

if you were adding air in wouldn't that oxidise the unburnt fuel and burn it in the exhaust.
my initial thoughts would be i think for off throttle emissions it would be good, but not while on the pipe.

[F5 Dave]

How did the RD400F US emmisions system work?

[Frits Overmars]

EXHAUST AIR INLET
The idea is to fit a reed valve(s) into the inside of the exhaust cylinder passage or header or divergent cone. The reed valve being arranged such that it could admit & cool fresh air into the exhaust system. The reed valve being opened & closed by the cyclic pressure pulses in the system. When there is a negative wave adjacent to the valve, it could open and admit fresh air into the exhaust.
This fresh cool air could possible displace some of the charge from the cylinder that passes into the exhaust prior to being plugged back. Potential benefit being that there could be a cooler charge in the cylinder at the time of EPC. Cooler = greater mass = more power.
Usual practical issues: mixture control, durability, noise, fitment etc.

Practical issue # 1: there is only so much suction available from the pipe. Adding an air entrance to the pipe will steal from the suction that is supposed to move the mixture from the crankcase to the cylinder.
Plugging cool air from the pipe back into the cylinder will not add any power because air will not burn. You might compensate for it by enrichening the mixture that does get sucked from the crankcase, but even then there would hardly be enough time and turbulence to create a homogeneous air-fuel mixture.
Maybe you could put a carburetor on your pipe air inlet, add a spark plug to the pipe and create a pulse jet.
More power? I don't know. More noise? Absolutely!

if you were adding air in wouldn't that oxidise the unburnt fuel and burn it in the exhaust.

Any unburnt fuel in the exhaust pipe had already been mixed with air before it got there. Adding cold air would reduce rather than enhance the risk of burning this fuel.

[husaberg]

Any unburnt fuel in the exhaust pipe had already been mixed with air before got there. Adding cold air would reduce rather than enhance the risk of burning this fuel.

okay but why does it burn when you do this with the 4ts and the rotaries?
Is it because the exhaust temps are hotter?

How did the RD400F US emissions system work?

i will post the pics but it had butterflys in the ex pipe and they stopped the evil unburnt hydrocarbons from escaping until later where they kill the other flying butterflys.

http://www.yeoldecycleshoppe.com/roa...cial-road-test

They put cats in the RZ but that still wasn't enough to get them legal in California which accounted for over 1/2 the bikes sold then for the US

[WilDun]

This word should be removed from anyone who works with machinery

its caused grief every time it’s used.

Don't be daft! - That would then totally screw up the word "J.A.F.A" .... J*** think about it!

[ceci]

Any unburnt fuel in the exhaust pipe had already been mixed with air before it got there. Adding cold air would reduce rather than enhance the risk of burning this fuel.

What you say is what happens in 99.99% of 2S engines, there is a 2S engine that the fuel can reach liquid ( spray) and not gaseous (steam) in the exhaust, which is it?