Vespa intake drilling out

Ok so i read the wiki and understand that. the thing is i really don't want to split the case, i have had good luck with case matching with everything inside than just washing out the engine with tons of carb cleaner

My question is, is there any point in drilling the intake out if i can't file the port inside?

Re: Vespa intake drilling out

Not much of one, no. It's really not bad splitting the cases, though, I promise. Remove the top end and just set the case small-side down on a stove on high. After a couple of minutes you can pull the small side off with no effort. Then flip it and cook the underside of the big one the same way for a minute or two, and the crank will just fall right out. Putting it back together is the same, you heat the case half and put the crank in, tap in with a mallet if you need some persuasion, then heat the small half and itll just slide right on.

Re: Vespa intake drilling out

Don't even think about doing it without splitting the case and pulling the guts out.

Re: Vespa intake drilling out

yeah.. most of the benefit comes from porting the inner area and cutting the crank.

Re: Vespa intake drilling out

yeah i just looked at my already split motor fucking shit is stupid small area. So i will be doing this once i get my fly wheel puller in. Hye mobyman how do you cut the crank i don't know how to measure it properlly.

Re: Vespa intake drilling out

Actually you dont even need the puller..just a rubber mallet, just give the flywheel a decent whack and a turn, a decent whack and a turn, etc til you can pull the flywheel off.

With the crank in front of you, crankshaft facing up and the closed area of the valve to your right, extend the opened area 4-5mm on the side closest to you, and 8-10mm on the side farther from you.

Re: Vespa intake drilling out

Bah the crankshaft is confusing. SO were do i measure from? Thanks for all the help also

Re: Vespa intake drilling out

Oh also if i do the stove thing will it ruin the bearing? Prob should just replace them since there out huh

Re: Vespa intake drilling out

The bearings are fine to real high temps. To preserve the seals maybe just 250F max. But why not just replace them. Quite a few perfectly fine bearings get tossed but they are cheap

Re: Vespa intake drilling out

Measure from the current open/close line around the outside diameter of the crank. I will try to take a picture when I get home. Bearings are good probly higher than your stove will go, as steve said. Crank seal you should just replace, it'll cost you $3 from zippy. A whole engine rebuild kit is $22 and includes new bearings, shoulder washers, gaskets, woodruff key, crank seal, etc.

Re: Vespa intake drilling out

yeah any pics would be great. I just ordered the engine rebuild from zippy might as well replace all the shit since it will be open.

Re: Vespa intake drilling out

good pics in these threads:

intakes & crank drawing:

http://vespa-ciao.nl/forums.php?m=posts&q=7347

crank cutting how to:

http://vespa-ciao.nl/forums.php?m=posts&q=8180

Re: Vespa intake drilling out

i would take more care to protect my bearings from getting metal shavings in them than that guy though, like wrap in ceran wrap and seal with silly putty, or use new bearings.

Re: Vespa intake drilling out

Yeah, my bearing were in the package waiting to go on while I ground this. I also used half a can of carb cleaner blasting out the crank arm bearing afterwards, and I sealed it with duct tape beforehand.

Mike, heres a picture of how to cut. I used the pink chainsaw sharpening bits for a dremel. took a while, but made a good grind. I also measured and then colored all sides with a sharpie before hand so I'd have a visual marker.

1212126075_vespa_stock_crank.jpg

Re: Vespa intake drilling out

Thanks guys i got a spare crank i'm going to cut tomorrow and pratice on.

How this went from case porting to a whole engine tune is beyond me

Think i should replace points and condesor while i'm at it?

Re: Vespa intake drilling out

You can test the condenser, just put a multimeter to it with red on the body and black on the wire, then swap them and it should decrease resistance gradually to around 50-20 ohms. Points just visually inspect: do they line up, are they clean?

Re: Vespa intake drilling out

Everrything works great just figured since i'm rebuilding one part might as well do the other

Re: Vespa intake drilling out

Yeah, if you got the extra $35 to spend at zippy, hit him up for a condenser and points. One thing: last condenser I bought from zippy, though a 2-wire, did not fit the Grande out of the box and needed some work done on the wires.

Re: Vespa intake drilling out

stupidity has occured in the way of a top crank.....

Re: Vespa intake drilling out

Meaning you bought one?

Re: Vespa intake drilling out

ya

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