ESE's works engine tuner

[richban]

and here Sir is your bill - $$$$$$$

330 US each plus 70 bucks for custom alts. Bargain in my book.

[seattle smitty]

Haven't forgotten your low-temp rod, Peewee, just waiting to see how it holds up for you. That stuff has a lot of zinc in it, which your base metal doesn't, and in asking around among welding professionals, I haven't found one who likes the stuff. Of course, they are talking about its use for joining metal, not for building up a surface. But some of them have had to spend a lot of accumulated time over the years grinding out low-temp filler metal that was used by someone else, and that didn't hold. So far as I know, none of it has an AWS spec or is certified in any way, and at least here the welding suppliers don't carry it. Now, I'm NOT saying it can't work; it very well might be just fine as you are using it, which is what I'm waiting to hear.

[peewee]

for something structural like joining two pieces together i dont think i would dare trust the brazing rod. besides the hts2000,durafix, etc, i also have some of the brazing rod from hobart but i havent used it yet. not sure what the difference is between it and all the others i have, maybe its all the same stuff. http://www.ebay.com/itm/Hobart-Low-T...item5d565af842

[F5 Dave]

So I thought casting ally had zinc in it to help it flow. Old Honda stuff used to look greyer than Yam.

[speedpro]

330 US each plus 70 bucks for custom alts. Bargain in my book.

Agreed, not bad for custom carbs

[jasonu]

Agreed, not bad for custom carbs

They are a total bargain at that price (if they work of course).
The way Richban was talking I thought $1000 was about right.

[AndreasL]

Hi all,

Other duties have keept me away from this thread so I have a lot of catching up to do.

Hope someone can give his thoughts about my matter.

Old piston port 50cc.
"New" after market cylinders are not very accurate but all lines up ok except the inlet port roof.
At BDC both piston rings are below said roof.
The upper edge of the piston sits above the roof by 1.5-2mm.
Put some light to the bore and it's easy to see looking in to the intake.

On one of my other project engines I am messing around with machining the cylinder base, test fit different Pistons etc. This one needs to be more of a simple quick fix.

I hear you say "Make a boost port and fit a reed" and absolutely, it's the sensible solution. For my "real" engine that is.

So, will the edge of the piston seal enough to not let it effect much or anything?

I have not tried but maybe EngMod2T is able to simulate even stupid and bad designs of this sort? For pipes I know to well that bad designs are no problem

Thanks a lot for any ideas.

[bucketracer]

Old piston port 50cc.
"New" after market cylinders are not very accurate but all lines up ok except the inlet port roof.

At BDC both piston rings are below said roof. The upper edge of the piston sits above the roof by 1.5-2mm. Put some light to the bore and it's easy to see looking in to the intake.

My guess is 1.5 - 2 mm will be enough of a seal but will the rings or ring ends get snagged in the inlet port?

This problem could not be modeled in EngMod.

[twotempi]

Can you machine 1-2mm off the base of the cylinder to lower ?? You may have to re=do the other ports but as it is the rings will almost certainly snag.

[husaberg]

Hi,
The outside diameter is 93.5 mm

"I note there seems to be a couple of different styles.
From a triangular early Rotax type to a asymmetrical chamfer an the intake side. and I think one for the 125 single"


:

Francis seeing as we are today on the thread and we are talking about carbs, can I trouble you to share some information on your carburettors.
They look incredibly short in intake length, as well as beautiful

[AndreasL]

Thanks for the input.

One of the ring openings are really close to the port opening but by turning the piston 180* around it will work.

I have a cylinder with the base shaved of 2.3 mm. That one is not ready yet and made fore slightly longer stroke. If doing the same to this combo the transfer port floor will sit to low etc.

So if we all think 1.5-2mm will seal I will take the easy way out with this one.
More takers are welcome.

[F5 Dave]

Can you machine 1-2mm off the base of the cylinder to lower ?? You may have to re=do the other ports but as it is the rings will almost certainly snag.

Almost certainly as the kawi triples had a bit hanging down for that porpoise.

. . . except plenty of us run centre pegged rings over boost ports. How wide the inlet is would be the deciding factor I guess.

[AndreasL]

The responsibility is all mine and the rings will work…I say.

So what I'm a bit uncertain about is if ~2mm will seal enough.
As I stand now I say it's worth a go.

Still interested in any thoughts on this matter. Even if just for theoretical reasons.

Thanks.

[Lef16]

Hello there!This is my first post here although i've been reading this thread for a long time.
Unfortunatelly I'm not able to read all 1000+ pages,so I'm sure I've lost a lot of information.I'm a novice tuner from Greece,mostly working with exhaust pipes.
Untill now I was working with trombone type pipes...before I discover the Aprilia GP style exhaust.I've read what wobbly said about header and diffuser % of the tuned length and diffuser steepest angle placement,but I cannot undertand the trombone pipe(1st dif angle<2nd dif<3rd dif angle) suck action compare to Aprilia type(1st dif<2nd dif>3rd dif),especially for lower rev enines(9500-10500 for example),and the effect on power curve.
Here is an exhaust I designed for a Yamaha 200cc engine for road use,68x57mm,~42-45hp,with almost 30% header and 67% diffuser,small 21.77 pipe to cyl ratio,shallow baffle angle and 935.2mm for ~10000rpm(194* ex).Unfortunatelly my Engmod2T demo has expired long time ago so I cannot run the simulator and see the pressure waves and power curve I was wondering if wobbly could tell us more about this design and if it was better to use the trombone pipe design.
Sorry if you're tired of reading this and sorry for my English.
Cheers!

[TZ350]

Unfortunatelly I'm not able to read all 1000+ pages,so I'm sure I've lost a lot of information. and sorry for my English. Cheers!

Your English is a whole lot better than my Greak.

Sorry I don't know enough to help but while you are waiting for Frits or Wob to reply, take a look at page 1000 there is a bit of a directory there that might help you find more info on pipes or anything else that you might be interested in like transfer angles, exhaust duct sizing etc etc.