ESE's works engine tuner

[wax]

Tell me what you guys use when your spacing a cylinder up. Im looking for the right material . I was thinking plastic but what sort.

[wobbly]

So the KTM has an ignition curve with only one thing remotely "right ".
About 15* at peak power.
Throw in a bunch of advance below 11,000 and juggle that with the PV full open point and suddenly mid range power will appear from nowhere.
Then correct the idiotic Aux port stagger issue and a huge mid increase is available.
This may need the main lifting a little as part of the " fix "to increase the peak and overev capability , but for sure the torque hole will be gone.

[TZ350]

Tell me what you guys use when your spacing a cylinder up. Im looking for the right material . I was thinking plastic but what sort.

Alloy plate.

[wax]

Thanks Im only going up 2mm and so it makes it a little tricky to make. I have a laser cutter so i can cut plastic if i want. I was looking for a good plastic to use

[husaberg]

Thanks Im only going up 2mm and so it makes it a little tricky to make. I have a laser cutter so i can cut plastic if i want. I was looking for a good plastic to use

1.6mm alloy spacer plus .4mm gasket with original gasket on other side.
I have one here i made with a drill and a dremill.
drill plenty of holes thus there is then no need to use snips that might bend the sheet.

[Frits Overmars]

Tell me what you guys use when your spacing a cylinder up. Im looking for the right material . I was thinking plastic but what sort.

Base gaskets must be rigid; the cylinder ears will break off if not sufficiently supported. KTM, Kawasaki and Honda cylinder ears are notoriously vulnerable.
Using 1 mm of paper gaskets is already asking for trouble if you do not use a torque wrench.
If you're thinking of using 2 mm plastic here, you can save yourself some elbow grease by binning the cylinder right away.

[tdc211]

Here ign. curve KTM 125 '18

Was that checked with a light?
My 16 ign curve nothing like that
150 cdi has more ign than a 125. at thats not even close to 15

[shnaggs]

NO - adding area to the lower part of the Ex port ( below TPO ) will not increase power anywhere , so is not a " design " element I would use for kart/GP or anything for that matter.
As I said we have been trying for years to reduce the duct volume , at the port end area , as well as using my nozzle idea at the exit face end.
BUT , reducing the lower area further only works effectively IF you have already sufficient Blowdown , matched to the power you are looking for.

If you are not going to be going into pipe changes, then there is alot to be had tuning the powervalve and ignition curves.
So if you are really serious about this , then an Ignitech driving a cable connected servo on the PV is the go , and of course the ignition can then be tailored specifically to whatever mods you do.

Sorry, I didnt mean take away from the lower portion of the port. I was going leave the main port alone, but maybe increase the Aux port width...they seem pretty small in comparison, but maybe they dont need to be that big.

But now after reading your other response, fudging the main port higher would possibly be a better solution. In this situation, would radiusing the upper portion of the port be beneficial, or just taking it up a bit would be better?

Will look into Ignitech, thanks!

[shnaggs]

Here ign. curve KTM 125 '18

Thanks for this!

[katinas]

Tell me what you guys use when your spacing a cylinder up. Im looking for the right material . I was thinking plastic but what sort.

Fiberglass plate with thin cooper layers, from electronic stuff. I use 1.5mm with " Wurth engine and housing sealing compound DP 300", for quick testing it works immediately, no leakage, no cracking. This year for testing I use four tube.
Like Frits write, stay away, if possible, from soft gasket as they always deform "ears" type cylinder. But if cylinder and head bolted to crankcase with same studs/bolts, maybe soft gasket is ok.

[peewee]

for cyl spacers, why not just use 6061 plate with klingersil homemade gaskets of appropriate thickness . this method can be made with simple hand tools like drill, dremel and scissors. maybe plastic could work but I don't see what advantage there could be

about the timing light. is that a reasonable way to plot the ign curve of the cdi box ? ive found this one https://www.innova.com/en-US/Product...58344023769935

[dutchpower]

Was that checked with a light?
My 16 ign curve nothing like that
150 cdi has more ign than a 125. at thats not even close to 15

Totaly different partno. '16 50439031000 '17 50439131000

[TZ350]

Looks like a great formula Rob. Clearly NF4 pipes aren't that common.

I go here for parts, Japanese TradeMe, RS125 pipes run about $300 NZD landed here in NZ. https://www.jauce.com/

Brought lots of different parts. Pipes, cylinders, wheels, NF4 fuel tank .....

[katinas]

And here I thought this site was allergic to piston port designs. I decided to take it to the limit with a divided intake. It takes a custom piston with a full skirt and a longer rod so the piston clears the crank web. I'm also considering Frits' 4 transfer design. It would fit on a stock crankcase with minor modifications. I'll need to finish modeling both versions to see if I missed anything.

Lohring Miller

Attachment 337764 Attachment 337765

Probably, intake duration can be little bit higher at deepest intake windows point, than at the frontal side. Would be interesting how engine respond with some angle on piston timing skirt.
Long time ago I had 75' IZ Planeta Sport ( Yamaha licensed copy) motorcycle with piston ported and C transfer 340 cc engine (add photo).

[F5 Dave]

I used to sandwich thin plate between two bits of thin plywood, clamp to cut without deforming plate.

Dremel with sanding drum will clean up without pulling it out of shape.