thank you very much for the advice
thank you very much for the advice
What is the model of slip roller that is best for rolling the Cold Rolled Sheet (especially the tailcone)?
In snowmobiles have never gone below 24 mm of tailpipe.
thank you
I use a cheap Woodward fab slip roll. For the baffle cone, slowly forming it by hand over a cone mandrel has been my go to method for a while. Go on eBay and type in “ hardy hole cone “. (I promise it is not porn) Start all the cone sections in your roller backwards so they do not acquire a flat spot in the initial pinch of the back roll. Just a bump backwards, then roll them like normal. Make a cone stop and bolt it to your roller, that will keep the parts from spiraling. Make the crank handle 100mm or so longer than the puny little thing they give you and thank me later. Laser cut parts are by far the best, but cnc plasma is acceptable if you adjust the settings so the parts match the laser parts. I try to stay away from the plasma parts. Remember “ crumbs make a cake “, .5mm difference per part will ruin your pipe, or leave you working backwards. It will take several years to feel efficient.
Thanks for your advice.
Is it better to buy a slip roller with a 1 inch roller?
In Canada the Princess Auto slip roll is about as small a diameter as you will find and works well. If you can wait they go on sale every once in a while. As Condyn said, cut the handle and extend it by 4" or so.
https://www.princessauto.com/en/12-i...t/PA0008536559
ok thank you
The Polyurethane roller that Elto uses looks to leave no flat ends.
You wouldn't want to get those gloves caught in it though.
Youtube Video below:
As Wob says "there is enough bird shit in that picture of the chamber to start an albatross colony" LOL.
Finally making some. This is my 1970 Kawasaki 250cc rotary valve F81M, or at least a close approximation of one. Methanol with oil at 30:1.
Push and go ignition system. Twin generator coils, rectifier reguator's and 50V 5500 mF capacitors and Ignitec DCCDIP2 Race setup for both channels firing into a CraneCams PS92N coil.
Wobbly pointed out that the coil will draw about 5Amps at max rpm. We will y generator may not support 5Amps.
I did tune a 90cc moped some time ago and measure it on dyno and now I am working on simulating it in EngMod.
Would Wobbly, Vannik or someone with more EngMod experience know, how can I better align curves to have a good base line for optimising the engine for further tuning?
I attached dyno curve and engmod sim.
I think the better power in higher revs in sim could come from not taking short-circuiting in account (I attached transfers directions sketch from engmod). Engine has 4 transfers 129° and one oval exhaust 181° and pistonport intake 160°. A transfers direction is too much towards piston center so I believe power is lower at higher rev in comparison with sim because of short circuiting from A to exhaust. It did reduce power at higher revs when I changed from Yam1 (black) to Yam12 (red) model (as seen on pic).
How can I make it more like dyno measurement?
Other engine info: Aircooled, 48x48mm (90cc), higher crankcase CR (old design from 70's), 1 ring race piston, custom exhaust, custom head insert with squish 50% piston surface, 0,7mm, PVL kart ignition with minimal retard with revs, dellorto 26.
Thanks.
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Way too many unknown variables to give any reasonable answer.
I will PM with my contact email.
EDIT - TeeZee another small detail that helps , run all input and power/ground/revcounter etc wires to the Ignitech on one side of the frame tube.
On the other side , the CDI orange/white output wires to the coil only.
Ive lost count of the number of Ignitechs that I have " fixed " simply due to RF crosstalk.
Also I used Magnecore wire from the coil to the 5K plug/cap ,as the huge spark power of the dual system , it easily creates havoc with misfires due to induction into the trigger/power system.
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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