ESE's works engine tuner

[WilDun]

It takes energy to shake (move) the engine, as in vibration, so yes the balance shaft does use power but it also saves wasted energy by stopping the engine actualy moving (30,000 times a miniute if it were Ryger)
As in the 700 twins case, I wouldn't want to fly without a balance shaft as I'm sure the engine would rip itself out of the engine mount in a very short order. No more cracked exhausts.
Just like a highly tuned woman, calm smooth exteria but the imbalance is still in there

Ha,Ha, all true, I guess all of life is really only one big compromise and we have to find our way around it.


BTW. ANDREAS,
Didn't mean to butt in just in front of your query, but that's what happens sometimes! - experts will no doubt be still at work I guess (Friday) - then, there's the weekend coming up.

[peewee]

Where are your piston ring gaps?

in the photo from two pages back did you see the vertical pencil lines at the outer edge of the D windows ? thats where the ring gaps are. this is a inside view as you can see how all the bridges are connected. removing the bridge between the D windows seems like a good idea but the lower portion of the bridge is only 5mm wide at the bore face and tapers thinner to a ball nose as it goes toward the reed block. if it were to crack somehow i think it would be a bad situation. since the upper bridge section is about 8mm wide, i could thin it a bit and widen the windows. another idea, depending how far around back i get the C windows, i could likely add two more of the small D windows, for a total of four. whether or not this is a good idea i dont know but i have seen some cylinders with multiple small C/D windows. what idea do you have ?

[twotempi]

If only the ring is in contact with the bore, will the cylinder wall need any coating? Cast from high silicon alloy, no coating, best heat transfer yet.

I think that Mercedes have a system for coating alloy cylinders that uses a paste that is forced into/unto the cylinder walls with an expanding roller arrangement.

Might not work with two-stroke cylinders with multiple ports though.

Does anyone have any info on this ??

[Frits Overmars]

in the photo from two pages back did you see the vertical pencil lines at the outer edge of the D windows ? thats where the ring gaps are. this is a inside view as you can see how all the bridges are connected. removing the bridge between the D windows seems like a good idea...

I don't think the piston rings will agree. Removing the bridge would give the ring ends too much free overhang.

since the upper bridge section is about 8mm wide, i could thin it a bit and widen the windows. Another idea, depending how far around back i get the C windows, i could likely add two more of the small D windows, for a total of four.

I wouldn't thin the bridge down either; the bottom-rear lip of the cylinder sleeve needs all the support it currently has.
Widening the C-ports would be best for power. If that's not possible you could widen the D-ports towards the C-ports.
But whatever you do, you won't find much power with your 172° exhaust timing. And the current blowdown angle.area is so small that the cylinder will be severly heated by spent gases entering the transfers at anything above a guesstimated 3500 rpm.

[peewee]

Frits im not at my computer now but I think the exh opened at 90atdc but remember I havent had a chance to optimize it in engmod yet

[Frits Overmars]

Frits im not at my computer now but I think the exh opened at 90atdc but remember I havent had a chance to optimize it in engmod yet

The 172° exhaust timing was based on your post # 18989, Peewee.
180° may be OK if you are planning some relaxed enduro riding, but for a competition bike 190° seems like the minimum to me. Ask EngMod and/or Wobbly.

[peewee]

Thnx for the help frits but I wouldnt even waste my time on a enduro bike.

[AndreasL]

BTW. ANDREAS,
Didn't mean to butt in just in front of your query, but that's what happens sometimes! - experts will no doubt be still at work I guess (Friday) - then, there's the weekend coming up.

No need to apologize WilDun.
This is a party and people talk to each other and changing subjects all the time. It's great!

Friday and all, but my questions isn't really Ryger, RSA or even on par with the hottest Buckets so if interest is low it's understandable.

I'm sure I will have some guidance as soon the gurus have a minute to spare.
With that said I consider all readers of this thread gurus. *flatter flatter*

[peewee]

wob, frits, is there any secrets about these small inlet ports ? so far what i did was make them bigger, with no sharp corners anywhere. it probly cant be seen in the photo but i made each corner as large of radius as possible so hopefully the air can follow without much trouble. even the inlet floor leading through the boyesen to the case has a nice radius . the ports may need to be bigger yet but this is as far as i made it tonight. theres a before pic to compare. every corner was sharp as a razor

[peewee]

The 172° exhaust timing was based on your post # 18989, Peewee.

i realized why the 172 sounded a bit off. the cylinder was meant for 80mm stroke but the crankshaft now is 82mm so the piston is poking a bit over the top

[breezy]

morning, ( 9.04 England) can anyone direct me to the page which had some details of a programmable ignition system i think it was for small rc engines. ive tried to look through the thread picture search but i cant see it. im also looking for details for the ignition curve on an early standard cagiva mito 125 engine , any help would be very appreciated .. thanks

[adegnes]

This one?

http://www.kiwibiker.co.nz/forums/sh...post1130830075

Another subject for the party-people...

I've ordered one of these for testing:

CE-i 100 with sensor SE-1

http://www.power-spark.de
Manual here http://www.power-spark.de/downloads/...ngl_2011_1.pdf

Seems like a good unit, has it's limitations, but for my use (variated engine) it should suffice.

Some features and limitations:

- 4 programmable ignition maps (and 10 preprogrammed maps - non of them seemed very useful, maybe for small rc engines)

- no computer needed, programming is done with a magnet(!), seems slow and weird but hey, no computer needed.

- Four adjustable rpm-points only (actually just three, the first point has to be 0rpm), this is very limiting for most, but for my variated setup it's ok.

- Easy setup; there's a "sensing mode" where it notifies you when it senses the magnet - just lock the crank at 75° btdc (what the manual say's it should be) and rotate the flywheel until the magnet is sensed - tighten up, done. If you manage to fuck up, you can adjust the 75° to something else, but anything under 75 limits how much advance you can run at high revs. (they give an example; if you set it to 70° btdc you can "only" run 35° advance @ 26500rpm, yeah thats gonna be a problem.)

++

I also asked Ignitech what they would charge for a dccdip modified to be used with an hall sensor - same price as the regular unit. So if this Power-spark is no good, I'll just get the tried and true Ignitech, and reuse the hall sensor pickup.

I'll post a small review when I get it up and running, if anyones interested.

[gamma500]

vhm racing testing exhaust port flow, 4° piston top vs flat top with radius.

https://www.youtube.com/watch?v=4KRwOObWCtA

other interesting videos on their channel also

[breezy]

This one?

http://www.kiwibiker.co.nz/forums/sh...post1130830075

yes, thats the one... thanks has it been tried yet?

[adegnes]

yes, thats the one... thanks has it been tried yet?

Yep, but I only for a short period, mostly reving on the stand, before I teared down my engine to resolve some issues and switch to the iame cylinder. Worked great and setup was no problem.

Here's a video of it sparking.
https://youtu.be/fNr3grvV6YE-