Well I ordered a ported jug from CMB and gasket set...

[markjs]

IDK what to expect. My bike gets up hills, but the steepest ones still take pedal assist. The town is very hilly, but by taking the more gradual ones I can get anywhere as is with no pedal assist, so I'm close to my goal as is. This on a standard, not ported PK80 Wildcat from California Motorbikes, with a 41 tooth sprocket.

So I am REALLY low on funds, and didn't get a piston and rings. IDK how many miles is on my original motor, but I'm sure it's nowhere near worn out. Do I need to "break it in" as long with same piston, new jug?

Anyway I'm only hoping for more oomph on hill climbs, and any top speed gain will just be gravy. I'm close to as fast as I wanna go already, but the ability to climb steeper hills, accelerate up slight grades that it struggles to get past 20mph currently on. I didn't, don't plan to upgrade the pipe, at least for now. First I can't afford a real expansion pipe, and I need a quiet machine. A modest upgrade would make me happy though, so I wonder if anyone might know what I should expect?

 

[Chainlube]

The issue with a store bought ported jug, what are the timing numbers? You are looking for performance but it might not work out. I only takes 1mm one way or another to spoil the whole thing.

 

[markjs]

Sucks cuz the gaskets I ordered aren't right, had to add another $20 in gaskets. I got these, as they look the right shape.

The ones I got in the kit I ordered were round and would have to be cut to match the port. I realize the ones I ordered might need cut too, but will need less cut out for sure, because they're already shaped about right....

This is the cylinder I got. I have to admit the ports look much more open, but no idea how much difference other than widening them was done.

 

[markjs]

The issue with a store bought ported jug, what are the timing numbers? You are looking for performance but it might not work out. I only takes 1mm one way or another to spoil the whole thing.

Well they do a lot of them, and I've seen them reviewed, and nary a bad word said, so it wasn't just a blind purchase. I suspect I will see a noticeable change, but less than I hope for with the limiting factor being my stock exhaust.

 

[Chainlube]

Let us know how well it works.

 

[markjs]

This is what got me to purchase it...

 

[markjs]

I have to say, looking at how narrow the surfaces for the gasket to mate up with the jug, it seems I might want to add a layer of gasket sealer goo, just to make sure things seal?

Just looks like an awfully narrow surface for the gaskets to contact, to make a seal...

Particularly on the intake side!

 

[markjs]

So Amazon shipping screwed me on the shipping, promised yesterday, then "updated" to tomorrow (2 days late).

I'm skeptical though, was thinking, with my intake manifold output end, being essentially round, and my exhaust pipe too being round, cutting gaskets should be wholly unnecessary, as well as all that porting will be to a large extent going to waste, because the restricted circular intake and exhaust holes not matching the full port size.

We'll see, if there's gains though, I expect their more due to slight changes in port timing. It's not like they're selling any better intakes or exhausts.

 

[robe]

I have to say, looking at how narrow the surfaces for the gasket to mate up with the jug, it seems I might want to add a layer of gasket sealer goo, just to make sure things seal?

Just looks like an awfully narrow surface for the gaskets to contact, to make a seal...

Particularly on the intake side!

I'd take a fairly wide single cut flat file and carefully flatten the mating surfaces of both the cylinder and the intake manifold. You will be able to see what is going on after a couple strokes of the file. The color of the surface will change showing the high and low spots. File until the color is even across the whole surface.
You'll have a much better chance of sealing it up

 

[markjs]

OK, well so far I am very unimpressed. In fact, seems to me it makes less power both in low RPM and high RPM, and maybe even have the piston striking the head.

I have no way to check squish gap, but I notice a rattle, could be four stroking (except the plug now says it's running lean), but it could be a slight but not catastrophic contact of the piston and the head or head gasket, IDK. I hate to pull the head after just getting it together. Worse still if I have to remove the jug and go back to the old one, the frame is so tight the studs have to come out to replace the jug.

I may not get back into it before tomorrow, but it definitely is no improvement, and possibly worse.