Running a spacer plate with a gasket on each side I have had nothing but trouble with excessive crush .
I now use grey case glue between the case and the alloy spacer,then use a single gasket to set the squish.
Re the KTM Aux port shape - DONT widen the bottom of the triangle , all this does is increase the vertical short circuiting from the A port.
Widen the top and square it up.
But doing this ( as well as lifting the main to increase the stagger ) will increase the Blowdown STA - then you would need to work on the transfers to get the balance back.
In TM kart cylinders I regularly have to drop the cylinder alot to get the Aux and or one of the transfers in the right place - then grind all the other ports up to get everything correct.
Bastard of a job , but hey , thats what wins races.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
Running a spacer plate with a gasket on each side I have had nothing but trouble with excessive crush . I now use grey case glue between the case and the alloy spacer,then use a single gasket to set the squish.
Exactly what we do too. Seal the spacer plate to the cases with YamaBond. Then set the squish with a base gasket.
Ha Ha, very good question Dutch.
To me that KTM STA file tells it all , we have the very latest cylinder from a respected manufacturer and guess what - its a fuckup.
The Aux ports are WAY to high , the ignition curve is seriously useless ,and all the transfers open together. ( Yamaha have done the same with the 2018 YZ125 ).
Maybe all the good 2T engineers have retired .
So looking deeper I would bet the PV is all wrong , and as I already know ,the smaller engines have serious issues with the A port angles.
Thus - with everything you look at being off base , am I surprised changing the ignition curve does nothing - Na I would be surprised if it did work.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
And is there a spacer increasing volume and allowing 6 speed space?
Na .... not that engine, you are thinking of this engine.
The one I have been experimenting with fuel injection on and which has all the bells and whistles.
Currently I am setting it up with a multi toothed flywheel for a different fuel injection systems ECU. The flywheel/generator is from a direct injection Aprilia SR50. I hope the flywheel holds together at 14,000 rpm.
i thought of welding the spacer to the cyl but never got around to it. gluing it to the cases seems like it would work fine. at the moment im using a gasket on either side and it hasnt given me any trouble
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
Dazz just did the transmission on Dennis 400 Superlight with the lube coating as well as a TM piston for me to dyno test the result.
He did the ring and small end pin as well.
Be interesting to see the result.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
Running a spacer plate with a gasket on each side I have had nothing but trouble with excessive crush .
I now use grey case glue between the case and the alloy spacer,then use a single gasket to set the squish.
Re the KTM Aux port shape - DONT widen the bottom of the triangle , all this does is increase the vertical short circuiting from the A port.
Widen the top and square it up.
But doing this ( as well as lifting the main to increase the stagger ) will increase the Blowdown STA - then you would need to work on the transfers to get the balance back.
In TM kart cylinders I regularly have to drop the cylinder alot to get the Aux and or one of the transfers in the right place - then grind all the other ports up to get everything correct.
Bastard of a job , but hey , thats what wins races.
Thanks Wobbly. I wouldn’t dream of taking more off the bottom aux, I’ve been learking around here too long to fall into that. Although I was surprised that you didn’t say I could widen the aux ports more, but I guess that would be too much and maybe not as beneficial, especially because of not having plugs for the wrist pin.
The " slippery shit " is what Micro Blue use on bearing races after super polishing.
Developed by NASA , Dazz has the got the rights to apply this coating here in NZ - only just got the sign off on the process.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
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Originally Posted by wobbly
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