I was rereading one of Paz's old posts about case induction and was recently given a crusty FUBAR'd E-50 to play with and I was thinking about doing the case induction mod. I saw the one Italjet kit in a picture in that post, but what are others that might fit the 43mm stroke 12mm wrist pin ideal. What yamaha/aprillia models did that fit. Just looking for some pointers in the right direction of searching. Thanks Performance Heads
crackstar
YAY my old post!
Do your self a favor and convert a case over to case induction and get it running with a non h20 cooled kit first. If it dose not work then you save your self a hell of a lot of fabrication getting the water cooled kit onto the bike.
h20 (not my project)
There are a lot of things you need to do to get a water cooled kit to even fit much less work.
- add material around the cylinder bolts to allow running a kit with a much larger bolt pattern.
Most scooter kits run larger cylinder bolts at a much larger spacing due to the increased diameter of the piston skirt.
- If the distance from the piston pin to the piston crown is not the same as on a puch you need to add a spacer plate to compensate.
Here is a shot of the cylinder installed with that spacer plate.
And another showing the start to the case induction.
Side shot with the reed valve installed.
Yeah, i figured as much with the assing of additional material, it doesn't bother me. My good friend is a TIG welder, and I have a CNC machine to take care of the spacers, relocation of stud holes, porting etc.. Im trying to take my time on this project, as much of a mental exercise and skill challage for me and my machine. I can't ride again till next spring. I understand your point of starting simple and proving the concept first. I figured while I'm waiting on other parts i could be searching for "just the right kit" and was looking for some brands/models etc that would be compatible for the puch stroke/rod length
Thanks though Paz all of those pics were what i already had in mind for what it would entail.
polini af1 is the most used scooter kit over there. Its for some aprilia. 70cc. Lots of work like paz showed. requires a much thicker spacer I believe from what I have aden on puch forum.
Yeps. Polini kit for the Aprilia AF1, that's your best bet. Some people also use minareli horizontal kits, but those are even more work and not really faster.
Also, the Polini kit for the Aprilia AF1 uses cylinder-reed induction, so you can save the case induction work.
This was on puchforum
Amongst other websites, yes ;)
The big plus about scooter cylinders BTW is that they use a 3rd transfer on the engine. A lot more work to make it match, but it also flushes a lot better.
Crackstar, did you take a picture of that top end before you took it apart? If you did, post it. That was the most fucked up top end ever.
Case induction and massive amounts of transfers, hmm, anyone think it might just be super cooler to build my own cylinder. Aluminum body, steel sleeve, i got stacks of 1" aluminum laying around the shop. If it were a sleeved design i could build it in layers, stack 'em together etc... I guess it'd be all in the portmap. if it were all air it would be easy to seal up the layers i would think the most important part for heat transference would be the top most area around the combustion chamber hmmm got me think thinking thanks all I'll keep in touch
wow, that would probably be the easiest way to make a cylinder... i always wondered about that. you'd just make your ports on the sleeve and then cut the aluminum roughly right and then finesse it once it's together.... wow. that's the kind of thing i want to try.
Ehm, it doesn't work like that.
You need a cylinder base and a cylindersleeve (The cylinderwall). The sleeve has to be inserted in the base under shrinktension (So the base is hot, sleeve is cold) or it has to be pressed. Both require a difference in size of about 0.05mm and in both ways the sleeve and base have to be absolutely 100% true.
If the base is too tight around the sleeve, the cylinder will just warp instantly when it gets hot, because the pressure can't go anywhere. It will sieze within a minute.
If the base is too wide, you get hot spots and cylinder will get soft siezes or overheat. The sleeve can even crack if the base is much too wide, because the pressure isn't evenly distributed then.
All and all, it's a lot of work. Best thing you can do is take a ruined cylinder and bore the old sleeve out of that for a base. There are shops where you can buy cast-iron cylinderwall-blanks. You could go there for the sleeve.
And talk to someone who knows about sleeve fitting about the tolerances b4 you put a new one in.
Absolute truth Roald, now bend your head around this idea. What if I was to do in an additive manner, start with an aluminum cylinder turned very under what the ID should be and "added" my transfers to the out side then added cooling fins, then sending it out to be bored to the final size and plated. Just another method I was tossing around in the brain
So you would start with the sleeve and then add material to the outside? If it's the same material, the heat expansion would be the same and in theory it would work.
I wouldn't dare to burn my fingers on that one and say if it works or not. I have no idea. It is an expensive gamble tho. The nicasil coating will cost ya dearly, and if the cylinder design isn't spot on, it will burn up or seize.
If you decide to try it out, please do post pics and results :D
I'll probably try the sleeve idea first, but in reality either way is gonna be stupid $$$ compared to buying a kit and making it work. I know of one shop that will do the boring and the plating, but cost will probably equal out to having my sleeve and jug bore machined and pressed together. I dunno, its one of those projects Im starting now in hopes it'll be done by next spring, when I can ride legally again..I guess i should buy plenty of pistons first, seeing if I really screw up my piston is gonna get FUBAR'd and my jug will get tossed in the recycling. Its just ideas right now. I'll post CAD drawings later, here in this thread, if I ever get any done.."
crack, maybe send 0ff y0ur CAD drawings t0 s0me0ne 1ike this
That's a company that sells CAD-tools
And most workshops charge you a shitload of money if you want to have something as complicated as a cylinder made by them.
Crackstar, are you going to make it watercooled while you're at it?
yeah I kn0w, just a t0ught
I have my own 3axis CNC machine. Its tight yo! It took a long time to get it calibrated just right and requires frequent checks and small adjustments. But its very accurate, one part at a time. So I'm really thinking about carving it out of some of the large chunks of billet aluminum I have around the shop. I found in some searching a company called LAsleeves which makes cast iron cylinder sleeves for anything, small and large displacement 2 and 4 stroke cylinders. Water cooled might be an option as it would seemingly take less time to carve a water jacket out then it would to cut all those fins. But in water cooling I'd have to leave a cylinder in the center which may make it more difficult to machine the transfer ports. But another option/idea is to stay air cooled for now and make the jug out of layers of thinner (.5-.75 inch) material stacked together and some how sealed, maybe grooves in each piece and a coresponding ring and press them together. the thinner layers would make it easier to machine the transfers in more of a fan like pattern, wrapping around the cylinder.
any of that make sense?
I think I am entering a world of pain....
continuing my oft interrupted chain of thoughts....
If I'm welding up an E-50 case to accomodate case induction I can weld it up to accomodate any configuration of ports, meaning I can keep it simple and make my transfers straight but paying attention to port roof angles and the angles that the transfer charge is expelled over the piston face. which makes it simpler.. maybe it is still a world of pain.
Building your cylinders is not a world of pain, it's hell.
But if and when you've mastered it, you'll be in heaven.
How about this idea for the cooling fins:
You make a circular surface on the cilinderbase and machine a groove in there. Then you start cutting out fins, with a matching circular base with a groove on the top and an extruding part on the bottom that you can press into the base and the previous fin. That way, you can build cooling fins the easy way. A bit like lego :P
There's just one problem with that idea... The fins have to be solidly connected to the sleeve, for heat transfer. So you'd be working with very very low tolerances. But as the stress is on the circular grooves, and not on the fit of the sleeve, atleast you won't get too much stress on the cylinderwall.
But its a puch E-50, each layer would look like a four sided comb, fins parallel to the cylinder
Hmm yes, good point. Doesn't have to be 4-sided tho, can be any shape you want it to be :P
I'm currently out of ideas. Like I said, building a cylinder from scrap is hard :P
Its my personality defect, I have to do everything the hardest way possible:)
Well, you get an A for effort :P
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