Honda Spree and Elite 50 Forums

I just bought a cheap large bore (63cc) cylinder for my Elite LX. Its not a great quality piece of work (did I say cheap!), but I got it thinking I could afford to play around with it a little to get used to the 50cc Elite.

The ports are poorly finished, so right now I am just cleaning them up by removing roughness from the casting and doing minimal airflow improvement. The problem I'm having is that the boost port holes are different sizes and shapes which I'm sure is a reflection of the quality of the cylinder. Consequently, I'm not sure what to aim for when cleaning them up.

I'm hoping one or more kind-hearted person has a decent quality Elite LX (pre-Dio engine, angled exhaust port) big bore cylinder laying around so they can take a picture or two of the boost port for me to use as a model.

Here are pics of the one I'm working on to give you an idea of what its like

Hopefully your pic or pics will be better than mine - I really need a more head-on view of the port from inside the cylinder.

Just remember, you odnt want your intake area perfectly smooth, if its too smooth the fuel will bead up on the walls and cause WORSE performance, rough surface keeps the fuel atomized but that looks too rough. You want rounded holes with a slight bevel so the rings wont catch. Keep in mind that porting without a supercomputer and a lab full of equipment is a "looks right to me" sort of thing.

Kenny_McCormic wrote:Just remember, you odnt want your intake area perfectly smooth, if its too smooth the fuel will bead up on the walls and cause WORSE performance, rough surface keeps the fuel atomized but that looks too rough. You want rounded holes with a slight bevel so the rings wont catch. Keep in mind that porting without a supercomputer and a lab full of equipment is a "looks right to me" sort of thing.

I'm familiar with all that. I'm keeping what I do smooth but unpolished. It's the shape and size of the boost port used on the LX I specifically need help with.

Clive.

I would look at the stock bore and scale it up as necessary.

Would if I could

I don't have a stock to compare it with, just 2 of the same big bores with shapes all over the place!

Clive.

Pick the smaller one and file it to match the larger.

Kenny_McCormic wrote:Pick the smaller one and file it to match the larger.

Well that was going to be my fallback option. Was really hoping for something more specific though.

Hmm, I suggest asking for pics of a stock boost port then.Make sure you port match the bore to the case.

exhaust side....you want that to be polished up very nice. Mirror finish. That will keep the carbon from sticking and help the back pressure flow.

Anyone have details on size/shape of boost ports