intake porting (how)

SteelToad /

I've seen a couple of people mention porting the intake, making sure the intake manifold, and the engine match up in a nice smooth line. Does anyone have any tips on how to do this. So far, I'm thinking of using some cardboard that will take an impression, and use it a a gasket, comparing the impression from both sides.

Is there an easier way ???

BTW: The duplicolor mirage (color changing) paint goes on extreemly smoothly and looks awesome. My bike is on its way from gray to green-purple.

Re: intake porting (how)

Hey there, that paint, is it in spray can? expencive ? Is it a enamal or laquor? I hate using the laquor (except the buzz!) I get a better... smoother job from enamel. I have did some porting, done see alot of need on the intake, unless the factory mis-matched it, but the exhaust.... on some you need to open up and polish, others, just polish out the casting slag. My Tomos (A-5) I only matched the intake to head, exhaust I just smoothed up alittle. You can really open a can of worms if you start trying to match the piston ports to the head. It`s a moped....Doug D.

Re: intake porting (how)

SteelToad /

The mirage paint is a laquer, it goes on nice and smooth, and I havent had a single problem with runs yet. It cost me $20 per kit, the kit consists of three cans.

A base coat, the mirage stuff, and sealer. It says on the kit that one kit will do 1-2 helmets depending on how you coat it. I bought two kits just to be safe. So far I've almost used one whole kit, and that did my headlight cover plastic, the side plastic, and the front fender & brackets. I've gone pretty liberally with the spray too. I figure the second kit will be plenty to finish the body of the bike and possibly a helmet.

As for intake porting, I know it's usually not a big deal, but the intake that came with the 70cc kit didn't match up at all well. At the bottom of the intake there is about 1/8 of an inch lip, and about 1/16 at the top. I know that can't be helping my flow any. I cleaned up the exhaust when the biturbo went on, like you said a little casting slag was all that needed to be ground off.

Re: intake matching

Go to a machine shop and ask for a can of Prussian Blue, or you can use paint, it's just harder to clean off when your done. Remove your cylinder head and intake manifold. Paint the surface of the manifold that mates to the cylinder and press it on the cylinder, the object is to find out how out of alignment they are. Use a scribe to mark the out of alignment areas on the cylinder and manifold and clean the prussian blue off with some thinner. Use a die grinder with a fine bit and grind off the excess, you'll have to blend the surfaces so they meet smoothly. GO SLOWLY, once it's gone there is no going back. DO NOT grind the cylinder intake or exhaust ports ( where the piston and ports meet ), you will alter the flow characteristics of the cylinder. Clean all your parts off in solvent to remove all metal shavings. Do your exhaust manifold the same way.

Re: intake matching

Hey Toad, did you take any pictures? I would love to see some before/after pics if you have some...

Re: intake matching

SteelToad /

I didn't take any before pictures, mainly because it was just a stock silver sprint. Not exactly worth the film. You can be sure I will be taking some when I'm done. With the dual halogen headlights w/ reflective covers, and the color changing paint it's gonna look frighteningly cool. The other thing I'm going to do is to paint the rims black. I'm just tired of them looking nasty when the grease spins off onto them.

Re: intake matching

SteelToad /

Thanx, that sounds like a winning plan. I was wondering how I was going to stop little bits of junk from falling into the cylinder. Duh, remove the head. (must be the paint fumes).

Re: intake matching

Steeltoad.They may have sent you the wrong intake for that jug.Check into it before you grind.

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