ESE's works engine tuner

[wobbly]

Sniemisto - you will have to ask your plating company the process they use.
In the cylinders I do here my final bore size is 0.1mm oversize, but the plating company then does a super rough honed surface preparation after that to increase adhesion.
Other platers may be different - depending upon what they go for as the final plating thickness.

[Muhr]

Chopped tow and epoxi?
Looks like you nailed the process.

Yes exactly 60% carbon fiber and 40% epoxy by weight. (density 1.4) and 25% extra epoxy that you squeeze out. I can imagine that it is a little more difficult if you do not know the exact volume of the finished product

[Frits Overmars]

In the cylinders I do here my final bore size is 0.1mm oversize, but the plating company then does a super rough honed surface preparation after that to increase adhesion.

I know what you mean Wob, but shouldn't that read 0,1 mm undersize? Anyway, most plating companies insist on preparing the bore themselves before plating. The problem arises when they also insist on doing the finishing touch after plating and honing. I know of more than one occasion where they turned perfect cylinders into bin-ready paperweights.
So I insist on them not chamfering anything and leaving the final honing to me.

[Muhr]

Coating Thickness of Nikasil®

In practical use the cylinder walls or sleeves are electroplated with a layer of Nikasil®, typically between 80 and 180 µm thick. Afterwards, the coating thickness is controlled using the custom-configured table-top FISCHERSCOPE® MMS® PC2, further outfitted with a NICKELSCOPE® module and the probe ENW3. Overall, this specialized instrument employs the magnetic measurement method (hall effect).

In the next step the cylinder barrels are milled and honed to improve their sliding characteristics. A final coating thickness somewhere in the range of 25 to 50 µm is aimed for, which requires extremely narrow tolerances to be met in the measurement procedure.

[wobbly]

Sorry Frits you have the wrong end of the stick.
For a 54mm bore they want me to finish to 54.1mm ie 0.1mm oversize , then they hone with what looks like 20 grit.
I dont know what that finished size is prior to plating , but I know Millenium say a coating thickness minimum of 0.05 , so that makes sense.
And yes ,I insist on removing flash in the ducts and doing the chamfers myself , they finally got the idea after I returned 4 cylinders to be replated due to complete shit huge 45* grinding on all the
transfers , when I had asked for none at all - as I just break the edges with a cotton mop.
That is a free lunch - 1/2 Hp repeatable,

Edit , someone always asks .I use Rexcut cotton fiber mounted points to do the finishing.

[DoldGuy]

Attachment 350961

Managed to get some dyno time today.

Blue:- RG50 Piston-Port/Reed setup

Green:- RG50 Piston-Port/Reed cylinder and head swapped onto the Rotary Valve bottom end.
No other changes to the cylinder carb or ignition timing. Just plugged the inlet and swapped it all over.

Red:- The Rotary Valve setup after some carb and ignition tuning.

Very nearly there, more fiddling next week.....

TZ, great results from your efforts! Can you share your jetting/timing changes?

[F5 Dave]

TZ, great results from your efforts! Can you share your jetting/timing changes?

Indeed interesting questions, but I'd perhaps question if there were timing changes whether it was optimised on the previous setup. Jetting you would expect.

[TZ350]

TZ, great results from your efforts! Can you share your jetting/timing changes?

Timing, not sure about that as when setting up the Ignitec's base advance it is easy to be a few deg out and that then offsets the whole ignition curve. Jetting, well the main went from 145 to 155 and the needle dropped a clip as you would expect when going bigger on the main. As F5 Dave suggests, I also paid more attention to polishing the ignition curve this time.

But I would not pay any of this to much heed at the moment as the vibration froths the fuel up something wicked. I need to sort the carb mounting out to reduce the amount of fuel being flung out of every orifice at 8,000 rpm. Gets a bit better at higher rpm. Will post a setup rundown when it is all sorted out.

[wobbly]

TeeZee , dont you program in say 15* flat line into the ignition then strobe it on preset rotor/stator lines set mechanically at 15*.
This ensures the base timing is perfect every time.

[Frits Overmars]

Sorry Frits you have the wrong end of the stick. For a 54mm bore they want me to finish to 54.1mm ie 0.1mm oversize , then they hone with what looks like 20 grit.

Then you're of course right about the oversize. My experience with more than one plating company is that they insist on removing some material from the bore themselves, the reason being that they want to make sure there are no oil residues in the material that would ruin their bath.

This is also the reason that it sometimes takes weeks before you get your stuff back: they collect all cylinders that have already run and treat them just before the bath has to be replaced anyway.

[TZ350]

TeeZee , dont you program in say 15* flat line into the ignition then strobe it on preset rotor/stator lines set mechanically at 15*. This ensures the base timing is perfect every time.

Yes I do, do that. I used to do it in a pretty haphazard way, of near enough is good enough using thick black marker pen lines. Made it plus or minus a few deg I guess. Although it got me in the ball park and was workable. The curve was then adjusted on the dyno. When the Ignitec said so many deg advance it may not have actually been that in reality. But the motor was happy which was all I was looking for at the time.

This time I took more care with the initial base timing using a properly setup degree wheel and strobe. It was much more accurately done this time. May explain why I had to adjust the old ignition map a bit to match the new motor.

[Condyn]

Are there any guidelines on how far the ring peg must stay from a B port? I have a 69.5 mm bore and the peg is 2-3 mm away from one of the B ports. If it makes any difference, I am using L-ring pistons.

[sniemisto]

For me 2mm sounds like being on the safety limit but I’m no expert.

IAME piston I was looking for is from 2 transfer port engine and might even overlap B port on 5 transfer cylinder. I was not able to get position degree of locating pin. Know that it can be relocated but not feeling comfortable on doing that.



TM Mini 60cc kart has locating pin center at back side according photos, but unluckily it is 41.89mm bore so just 0.05 over my limit. Also with L-ring.
Relating to my previous question, is there dyno data on friction loss effect with L-ring compared to plain ring somebody’s willing share?

Thanks for answers on plating. Need to try communicating with plating company. I’m dealing with local 3rd party who is sending big batch of cylinders to plating so don’t have straight contact.

Athena cylinder comes from factory with huge uneven port chamfers, luckily those will be mainly removed during porting.

[yatasaki]

Sniemisto, first find out for which kind of plating is your ring (mostly they are for cast iron liners) and there are two types of rings, steel and cast iron (all plated), steel ones withstand quite a lot percentage of exhaust width. For replacing peg there is no worry, there is material added for central peg or try to find iame, vortex, TM piston with central peg. If you are 0.05 in oversize machine it, they are conical for 0.07mm in 46 mm of lenght.
We are using these pistons in our races and are top offer. There are 5 and 7° conical and radius dome (as on your picture). Radius ones are much safer cause of ring groove being too thin on conical ones.

[TZ350]

.
2Stroke Stuffing's dyno can measure well enough to see actual changes in performance when trying new ideas.

Here is a megaphone exhaust:- https://youtu.be/fiL1FBT8DUs