ESE's works engine tuner

[F5 Dave]

I've moved stuff off key and regretted it having to replicate work. Ignitech makes it so easy to adjust from a known point. Getting back to known is a drag.

[katinas]

with a Hammer.

There is other, 100% guaranty way to remove flywheel, if nothing helps. Tried this once in young days, but think first and last time.

What ever I did, could not remove big flywheel magneto ( 165 mm dia.) from my first project bike with outboard engine (found old pic).
Then simply spin engine to 5000 rpm and flywheel easy moves up, falls on garage wooden floor and was standing without any movement. Only after some seconds I release that this piece not only simply standing, but rotated 5000 rpm at the same time . Only after 10 seconds this monster begun slowly move to the inside of the garage. It was time to do something, I quickly close garage door and the war began...........
When the Peace come after sooooo long time, inside of my friends garage was unrecognizable. It was absolutely colorful, mostly black from old used oil that he was kept in glass bottles. Other colors was from paints cans. All tools, rags, trash, was everywhere, but the bike was not damaged only black.
What was happen if the bike was arranged to outside way in the garage.....
I did not use this flywheel any more, just remember, made total loss ignition with points and battery, later cdi with small rotor.

[_____]

I found out the most important thing for any propper cone connection is to bore the end of the hub cylindric to the end-diameter of the cone plus 0.1mm.

This makes the flywheel suit on the crankshaft like a glove. (or what ever conical shaft-hub connection we are talkin about)
Very fine valve grinding paste is also a good idea, but only if something is very off.

Cheers Chris

[Matt@TYGA]

Also concur on the dry taper for the flywheel.
Made a handful of flywheels for things, with and without key grooves (just hand filed) which were just for a rough guide when fitting.
As long as the taper is a good fit and the correct taper of course then the key does nothing more than help locate.
My ancient Chinese mini lathe in the shed does a reasonable job of cutting internal tapers, but some lapping with fine paste is usually required

[Frits Overmars]

No doubt a key can be helpful in fitting a flywheel in the correct position. My practice of omitting it stems from experience with moped engines that were older than me,
when I was 15 years old.
When trying to build one running engine out of three non-running ones, the male and female tapers did not always match 100% (99,9% is not good enough).
So, in the usual twice-a-week seizure, the flywheel would rotate on the shaft and the key would destroy the tapers.

A second reason for omitting the key is that sometimes you want to set the ignition beyond its built-in limits. And if you can't move the stator far enough, you need to move the rotor beyond what the key would allow. Today we can set the timing wherever we want with a couple of keyboard clicks; in those days we had barely left flintstone ignition.

The third reason: when I started working on the first Rotax 250cc tandem-twins in 1980, I noticed that the crankshaft seals ran on the hubs of the coupling gears,
and air could creep in through the key grooves in the hubs, causing a couple of nasty seizures. That didn't improve my sympathy for keys.

Frits, would you concur that the advise you give would be relevent to the work you helped with the aprilia engine only and that there could actually be other ways of improving engine power. have you been seen or experienced alternative methods? and if so would you expand on such improvements?........

I assume that you're not referring to the advise regarding the tapers, as that wouldn't improve power.
I've worked with two-stroke engines for 55 years now, so my advise is not based on Aprilia experience only, though I learned a lot from Jan Thiel, almost as much as from my own countless mistakes. By the way, Jan and I go back way beyond Aprilia; we got together at Bultaco, Minarelli and Garelli, to name a few successful brands.

I have seen a lot of alternative methods, one even more daft than the other, like corrugated crankshafts that should act as ventilators (they would, if they would rotate ten times as fast), golf ball dimpling all over the place, and 'flame channels' in combustion chambers, that greatly improved detonation, as did thermal barriers on chambers and piston domes.
The alternative methods that do work, like supercharging and nitro, are forbidden in most branches of motorsport. With one exception: E85 is considered a regular fuel and it is permitted in many branches of motorsport. It works better than some expensive racing fuels... But don't spread the word.

[yatasaki]

on[/I] the hubs of the coupling gears,
and air could creep in through the key grooves in the hubs, causing a couple of nasty seizures. That didn't improve my sympathy for keys.

Especially when the shaft is non-conical, you have to soak key in silicone to seal.
For each tomos manual gearbox this is a must.

[breezy]

No doubt a key can be helpful in fitting a flywheel in the correct position. My practice of omitting it stems from experience with moped engines that were older than me,
when I was 15 years old.
When trying to build one running engine out of three non-running ones, the male and female tapers did not always match 100% (99,9% is not good enough).
So, in the usual twice-a-week seizure, the flywheel would rotate on the shaft and the key would destroy the tapers.

A second reason for omitting the key is that sometimes you want to set the ignition beyond its built-in limits. And if you can't move the stator far enough, you need to move the rotor beyond what the key would allow. Today we can set the timing wherever we want with a couple of keyboard clicks; in those days we had barely left flintstone ignition.

The third reason: when I started working on the first Rotax 250cc tandem-twins in 1980, I noticed that the crankshaft seals ran on the hubs of the coupling gears,
and air could creep in through the key grooves in the hubs, causing a couple of nasty seizures. That didn't improve my sympathy for keys.

I assume that you're not referring to the advise regarding the tapers, as that wouldn't improve power.
I've worked with two-stroke engines for 55 years now, so my advise is not based on Aprilia experience only, though I learned a lot from Jan Thiel, almost as much as from my own countless mistakes. By the way, Jan and I go back way beyond Aprilia; we got together at Bultaco, Minarelli and Garelli, to name a few successful brands.

I have seen a lot of alternative methods, one even more daft than the other, like corrugated crankshafts that should act as ventilators (they would, if they would rotate ten times as fast), golf ball dimpling all over the place, and 'flame channels' in combustion chambers, that greatly improved detonation, as did thermal barriers on chambers and piston domes.
The alternative methods that do work, like supercharging and nitro, are forbidden in most branches of motorsport. With one exception: E85 is considered a regular fuel and it is permitted in many branches of motorsport. It works better than some expensive racing fuels... But don't spread the word.

Yes your right Frits, not tapers thanks for reply Have you been able to do any more with regard to your multi port central scavenging concept?

[Frits Overmars]

Have you been able to do any more with regard to your multi port central scavenging concept?

At the moment it's proving that my exhaust duct ideas work. Despite the mild 190° exhaust timing, the pipe pulses are the strongest I've ever experienced.
Which is great, except that the torque dip at 2/3 of max.torque rpm is also the worst I've ever seen. We're working on that now, other activities permitting.

[ken seeber]

Ignition advice wanted. A friend has an approx Honda 1990 CR250 engine on his superkart and the ignition CDI is cooked. Is there an alternative (aftermarket etc) to just getting a new Honda part item, which apparently are rare and/or expensive.

Any help would be appreciated....gotta keep the competition alive..

[F5 Dave]

Here's one prepared earlier.


https://www.bikeside.de/IGNITECH_1

I bought a few of these, meant for CR (they put them together in kits, mine just happened to be for CR250 but I didn't use the curve supplied on the disc) but used on my RZ, a TF, MB, GP etc.

Or email them, if can't find the kit, they speak English.

Or buy locally and I'll mail you the curve.


Actually I used CR250 stator and Rectifier Regulator/ Capacitor on a couple of my race bikes. They drive an Ignitech easily.

[peewee]

Ignition advice wanted. A friend has an approx Honda 1990 CR250 engine on his superkart and the ignition CDI is cooked. Is there an alternative (aftermarket etc) to just getting a new Honda part item, which apparently are rare and/or expensive.

Any help would be appreciated....gotta keep the competition alive..

theres a few on usa ebay right now for 150usd. im sure theyll ship worldwide. maybe he could use cr125 box if the connector is the same. theres probly alot of 250 aftermarket stuff but it may cost more. vortex is one aftermarket option but its 550usd.

[husaberg]

Ignition advice wanted. A friend has an approx Honda 1990 CR250 engine on his superkart and the ignition CDI is cooked. Is there an alternative (aftermarket etc) to just getting a new Honda part item, which apparently are rare and/or expensive.

Any help would be appreciated....gotta keep the competition alive..

Here's one prepared earlier.


https://www.bikeside.de/IGNITECH_1

I bought a few of these, meant for CR (they put them together in kits, mine just happened to be for CR250 but I didn't use the curve supplied on the disc) but used on my RZ, a TF, MB, GP etc.

Or email them, if can't find the kit, they speak English.

Or buy locally and I'll mail you the curve.


Actually I used CR250 stator and Rectifier Regulator/ Capacitor on a couple of my race bikes. They drive an Ignitech easily.

The 1990-1996 Cr125 shared the same staor as the CR250 89-92
Dave used a post 98 Stator as did Speedpro not sure re the years think there was a 6 pole and 8 pole with differing outputs but from memory less than 10-25 watts.
They have a real small flywheel same size as CR80. 78mm or so.
I think the KTM kokusan set up is the same setup the bits might be more useful in the future as the Honda parts become scarce.
Husky and others also used the same ignition with different backplates
http://www.cafehusky.com/threads/08-...-do-that.2755/
these style stators are cheap moose racing etc
https://www.rmstator.com/en_ww/produ...7-2016-rm01374

[Michael Moore]

Ken, Jeff Henise has been using the hpi.be ignitions on the F37, CT1, YCS1, customer Honda 160/175 twins, etc and seems to be doing well with them.

cheers,
Michael

[F5 Dave]

Hpi is quite expensive. Ignitech is the biz.

[F5 Dave]

I'm using $10 Chinese rec/regs and 2200uf caps these days if not already fitted. If not already sorted let me know and I'll sort you out.