ESE's works engine tuner

[peewee]

hey guys you ever noticed on a cylinder reedvalver theres usually quit a bit of extra space on top,below and behind the reed cage ( in the area where the reed screws set when the block is mounted in the cylinder). im sure someones tried filling in some of this area with epoxy. anything to be gained from it ??

[Drew]

hey guys you ever noticed on a cylinder reedvalver theres usually quit a bit of extra space on top,below and behind the reed cage ( in the area where the reed screws set when the block is mounted in the cylinder). im sure someones tried filling in some of this area with epoxy. anything to be gained from it ??

Ooooooohhhhhh, this one applies to one of my motors....I wait with no patience at all...

[koba]

It's pretty tight once you bolt it altogether on most I've seen.
I've kept as little volume as possible when working in this area, seems logical.

[Drew]

It's pretty tight once you bolt it altogether on most I've seen.
I've kept as little volume as possible when working in this area, seems logical.

Soooo, some blue-tac to see what sorta volume we're talking about when it's assembled, and then repeat with glad wrap and devcon if it's quite a lot?

[wobbly]

Again this is the old story of trying to put specifics onto a huge generality.
The reed cavity of course is connected to the case, and it depends entirely what the total volume is,as to the advisability of
filling in the so called dead areas.

I have found that unlike a full noise rotary valve engine there seems to be no power increase if the case volume is made bigger than a 1.3 ratio when using reeds
be they direct into the case or cylinder mounted.
And another generality seems to be that the crappyer the transfer ducts, the ratio should tend the other way toward a smaller 1.4 ratio.

If the case was too small to start with and you fill the reed cavity dead areas, this will make it worse, and vise versa, but as all the factories are now tending toward making the reed box
smaller and smaller it would seem that filling the cavities and also filling the volume in front of the reed ( to the point where you would think the flow would for sure be affected badly )
then I would say its a good thing AS LONG AS YOU ARE MEASURING AND CORRECTING THE TOTAL CASE VOLUME.

[koba]

Soooo, some blue-tac to see what sorta volume we're talking about when it's assembled, and then repeat with glad wrap and devcon if it's quite a lot?

Sounds like a plan!

My MB one is all part of a home made adaptor, tight enough to need screws with smaller heads, had to grind it out to fit thicker reeds!

Still, I'm no expert...

[koba]

Again this is the old story of trying to put specifics onto a huge generality.
The reed cavity of course is connected to the case, and it depends entirely what the total volume is,as to the advisability of
filling in the so called dead areas.

I have found that unlike a full noise rotary valve engine there seems to be no power increase if the case volume is made bigger than a 1.3 ratio when using reeds
be they direct into the case or cylinder mounted.
And another generality seems to be that the crappyer the transfer ducts, the ratio should tend the other way toward a smaller 1.4 ratio.

If the case was too small to start with and you fill the reed cavity dead areas, this will make it worse, and vise versa, but as all the factories are now tending toward making the reed box
smaller and smaller it would seem that filling the cavities and also filling the volume in front of the reed ( to the point where you would think the flow would for sure be affected badly )
then I would say its a good thing AS LONG AS YOU ARE MEASURING AND CORRECTING THE TOTAL CASE VOLUME.

Interesting.

I'm soon going to revisit all my measurements, I think I have underestimated the effect of a wee grind here, a little bit off there...

[Drew]

Interesting.

I'm soon going to revisit all my measurements, I think I have underestimated the effect of a wee grind here, a little bit off there...

Isn't Wob saying that wouldn't really matter fuck all?

Re the 'dead' area though, does it matter? Why wouldn't the flow just treat it like a wall and sail right on by?...






considers putting blue-tac away, but likes squishing it around

[koba]

Isn't Wob saying that wouldn't really matter fuck all?

Re the 'dead' area though, does it matter? Why wouldn't the flow just treat it like a wall and sail right on by?...


considers putting blue-tac away, but likes squishing it around

S'bout volume and resonance a fair bit too, right?

[koba]

Wob, does it matter a shit? I just made mine tight as it seemed logical to keep minimal section changes in the inlet tract, as out of the way as it is...

[jonny quest]

Can someone provide the name of the electrical trigger box that's found somewhere in these 950 pages please? I've been looking for an hour and I didn't bookmark that page when I first ran across it.

I'm looking for a electrical device to shut off a electronic powerjet after a certain RPM, seeing as my CDI box doesn't have this capability

[husaberg]

Can someone provide the name of the electrical trigger box that's found somewhere in these 950 pages please? I've been looking for an hour and I didn't bookmark that page when I first ran across it.

I'm looking for a electrical device to shut off a electronic powerjet after a certain RPM, seeing as my CDI box doesn't have this capability

ignitech............

[speedpro]

For the area behind the reed stops, if fitted, it isn't going to make any difference to the flow, only to the volume of the cases. I've been very careful keeping the inlet tract as constant a cross section as I can manage. From where the tips of the reeds are at full open I've tried to keep the duct the same size as far as possible. It looks restrictive sometimes but I keep trusting that it's right. Same between the carb and reeds. Especially with a splitter and a bunch of devcon it can look quite restricted when the reeds are fitted and closed. With the reeds removed though it looks like a jet engine intake each side of the splitter and I can see how the air would flow nicely. Back to back tests with standard (old) Yamaha reeds on the dyno yielded good gains plus I could clearly hear a difference to the sound of the intake.

A thought I've had is that having solid reed stops or the equivalent built into the reed cavity, could actually impede the reed action, as the air trapped behind the reed as it reaches full open could slow the reed down as the air is squeezed out, or it could act like a spring and bounce the reed closed, or if the reed manages to get fully open against the stop it might hesitate to close as air struggled to return behind the reed as it starts to close. Or that effect might actually be a benefit. Friggin 2 strokes, who knows.

[wobbly]

EVERYTHING makes a difference in these fekin things, dont assume ANYTHING.
I have been wanting to try reed spacers on a KZ2 kart engine for ages, having spotted one on the grid fitted to the enemy's engine.
So prior to the Nationals at Easter I finally got our good TM onto the dyno to recheck the performance with a new "high inertia" crank.
The crank replaced the so called " factory special tune " version that costs some E600 from TM for a KZ10.
I got hold of the wheels for an old KZ9 that were very simple in that they are plain disks with only 1 piece of Mallory opposite the pin for balance - nothing else.
So I added two 19mm by 19mm Mallory slugs in each wheel, on centreline so the balance isnt affected, only the rotating inertia.
Short story is this mod lost 1 Hp all the way to 13200 where it crossed just under peak Hp - high inertia = harder to spin up ( I think )
After peak Hp the lines diverged, and at 14500 the thing made 6Hp more,up from 35 to 41, with a much smoother roll-off ie no " fall of the cliff " effect.
This enabled at least a 1/2 tooth to be added at the rear, well off setting the 1Hp loss with way faster off corner acceleration due to gearing torque multiplication.
I added a 5mm reed spacer and this lost around 2Hp below 11,000,gained 2 Hp between 11,000 and peak, then lost that 2 Hp and more after, getting progressively worse.
So I started playing with reed and backup tensions,using softer main petals I got back the loss under 11,000 and with wider/stiffer backups,spaced further away from the mains
I got back nearly all the overv loss.
So of course I then took the spacer out to recheck, and it made even more power everywhere,fucked if I know,enough to drive you up the wall - but hey it took the National title so who's complaining now.

[koba]

Yeah, I'm going slowly mad thinking about mine, have the ignitch pulgged in now, unable to improve on a straight 15 degrees all the way through.

I'm sure I could spice it up in the mid range and improve response more, main thing im looking for is over-rev though as that will net me the best return on the track.

I'd be convinced it is the pipe, but I've had more revs on the same one before, too much has changed to be sure but it may be the head.
I wish I had the resources to test each change properly, but I know that would likely lead to more questions and more madness.