Se50 custom bore kit ???? Help appreciated..

[808se50]

So I have a 87 elite se50 with the af05e block.I want more hp out of it been doing research on it and everyone says that the sa50 parts are interchangeable but I did notice that the sa50 has a 12mm pin and the se50 takes a 10mm pin. I did find a 47mm piston with a 10mm pin I was thinking about taking it to a machine shop and boring the stock cylinder but not sure if it's safe... I was also thinking since I'm gonna go that far in if I could stuff a sa50 stroker crank in there and if anyone knows if I have to machine the block to put it in. which would solve my problem for the bore kit to fit in that 12mm pin. Info anyone? ?? Much appreciated. .

[bonesv]

I believe there is a different cylinder kit for the '87 se50 af05 -vs- the '88-'93 sa50 af05.

[808se50]

Is it possible to bore the stock cylinder to a 47mm piston or is it too big?

[808se50]

The only upgrades done on it was CT racing manifold,34mm koso carb,polini 2g springs and oil pump delete. Next Planning on doing the cdi electronics and figuring out how to bore it out and stuffing it in with a 47mm piston..... really wanting to machine the block to stuff in a stroker sa50 crank!! Help me out if anyone done or heard of someone doing this before or I might just having my hopes up for a dead end.

[bonesv]

I believe there is a different cylinder kit for the '87 se50 af05 -vs- the '88-'93 sa50 af05.

your right, Im sorry i didn't see the *87. Bones, does the 87 use the spree style engine? I'm always goofed up on those older models

No, not the spree motors, the '85-'87 Aero's and '87 Elite's (se50) use a different cylinder kit than the '88-'93 Elite's. That's how I understand it. But everything in the USA is af05 before '94, go look it up.

(808se50) I would hesitate to bore the stock cylinder that much, it will probably change the port timing so much you wouldn't get it to run and probably seize it quickly. I would try to find a Malossi 65cc kit for it and I think that's about all there is for it. Gears are really scarce also so I would say top speed could approach 55-56?mph on the 10;1's??? with some big(3.50x10)tires....Get a much smaller carb...21mm?or so. Stuffer crank not available for that, afaik. Have fun whatever you do! And I do appreciate your enthusiasm!

[1man8scoots]

87 is the same as the other af05e. Some early aero used a different crank so they needed a different kit. I believe its only the 84 thats different with the crank size. 85- 87 is a ok. I have a malossi kit on my 87 se50 made for 85-87 aero and 87-93 honda vision/elite.
Also 85-87 aero used the different 2 bolt intake I think. 84 used the 4 bolt intake. 87 se50 is 4 bolt.

[808se50]

So bottom line dont bore stock cylinder?

[bonesv]

So bottom line dont bore stock cylinder?

I would not. There's no one that I have heard of that has, or even tried to. Just say'in....I would not.
There's more to it than just fitting a piston.
Wait! just for fun, take it over to a machine shop and ask them about doing this job for you.
They will give you the answer also.

[808se50]

I already talked to my machine shop theg said its possible just that in might run hot because of the cylinder walls being so thin and also still have the stock exhaust trying to find another exhaust that fits it.

[1man8scoots]

You absolutely must re port the cylinder as well after re bore. Who cares if it runs hot if you never hit 7k rpm due too retarded timing. Do a little research about boring a 2 t cylinder the decide to bore a stock cylinder or not.

[808se50]

Graphite9 would it work for the af05e that I have? And how big is the bore kit you have? Aslo does anyone know if you could fit a sa50 crank in that block and im trying to figure out the variartor situation I dont know how to tell if its restricted or not?

[1man8scoots]

A crank from an af16 won't fit in an af05e.

[808se50]

Thanks..

[Wheelman-111]

Greetings:

Polini and Malossi 47mm cylinders yield 65ccs on the short-stroke variated SE05 engines. Both will give much more spirited acceleration and a nudge up in top speed to 42 or better. Add a pipe and 45 is pretty likely. Gearing can take it to near 60, but the tall Malossi 2:1 primaries at 7.83:1 make 0 - 10 MPH take-off painfully slow unless a full kit and carb are added. See Flash 2, circa 2009.