Wanting to port my 100c intake and exhaust. No experience porting.

[OrionSphere]

I don't have a Dremel, just files, but I can get one tomorrow. I've watched a couple videos but I don't think they explain as well as you guys

My max speed is 30mph and my ports look disgusting, wanting to increase speed

 

[ImpulseRocket]

First thing you need is a degree wheel. You can buy one or make one. That allows you to map your current ports. Once those are mapped and you know what you have to work with, you can then plan out a port map, or see if somebody else has a port map for your engine that suits your desires.

Once that is figured out it's a good idea to draw your boundry lines inside the cylinder so you know where to stop.

I would suggest watching a bunch of videos before diving in. Tinmans Saws is a great channel that demonstrates a lot of porting theory and how-to.

As for the Dremel, skip that and get a Wen Rotary tool WITH flex shaft. That flex shaft tool makes things easier. I've been using one for 5 years, it still works great.

 

[OrionSphere]

First thing you need is a degree wheel. You can buy one or make one. That allows you to map your current ports. Once those are mapped and you know what you have to work with, you can then plan out a port map, or see if somebody else has a port map for your engine that suits your desires.

Once that is figured out it's a good idea to draw your boundry lines inside the cylinder so you know where to stop.

I would suggest watching a bunch of videos before diving in. Tinmans Saws is a great channel that demonstrates a lot of porting theory and how-to.

As for the Dremel, skip that and get a Wen Rotary tool WITH flex shaft. That flex shaft tool makes things easier. I've been using one for 5 years, it still works great.

I thought I could just clean up the ports without measuring?

 

[Chainlube]

I don't have a Dremel, just files, but I can get one tomorrow. I've watched a couple videos but I don't think they explain as well as you guys

My max speed is 30mph and my ports look disgusting, wanting to increase speed

Yea, you can clean all that out with files, I've done it many times. We need to see a picture of the transfers too. Most important is to bevel the inner lip of the ports so the rings don't hang up there.

As for the Dremel, skip that and get a Wen Rotary tool WITH flex shaft. That flex shaft tool makes things easier. I've been using one for 5 years, it still works great.

I've had a Dremel with a flex shaft for 35 yrs.

 

[OrionSphere]

Yea, you can clean all that out with files, I've done it many times. We need to see a picture of the transfers too. Most important is to bevel the inner lip of the ports so the rings don't hang up there.


I've had a Dremel with a flex shaft for 35 yrs.

When I open er back up I'll send pics

Yesterday I opened it up and left my bike outside, it rained inside the motor which SUCKED. Not a ton but alot of moisture. Tool me like 1.5 miles of pedaling and starter fluid to combust the excess water out and it's running now

 

[OrionSphere]

You can see how much excess metal is in there. By cleaning it up, y'all mean filing that off, right? I'm not trying to file all the edges all the way around to make it bigger, just widen the opening where the inner cylinder metal is not the same size as the actual port

Also, how much power can I expect to gain from cleaning up my ports?

I'm getting 30mph with my 100cc and I feel like I should be able to go much faster than that, I only weigh 140 pounds

 

[Wyvern]

Yep, remove the flashing to match what the original cast should have been.

The flashing is thin, you'll be able to go through it very easily.

As others noted, you want to make sure the lips of the ports are slightly rounded in.

As to power gains? Probably not much, but you might be able to feel it.

What is the gearing? IIRC a plain Jane 2 stroke china doll is good for 30-35mph.

Avenger, Phantom and Minarelli are good for 50mph.

 

[OrionSphere]

Yep, remove the flashing to match what the original cast should have been.

The flashing is thin, you'll be able to go through it very easily.

As others noted, you want to make sure the lips of the ports are slightly rounded in.

As to power gains? Probably not much, but you might be able to feel it.

What is the gearing? IIRC a plain Jane 2 stroke china doll is good for 30-35mph.

Avenger, Phantom and Minarelli are good for 50mph.

Stock motor gear, 36T sprocket

I have a Phantom 85 on hyper but I'm waiting on replacement front mag wheel

There's alot of options for power gains, ALOT. In your opinion what are the best ways to increase power?

Also, running 40:1 rn

 

[Wyvern]

Stock motor gear, 36T sprocket

I have a Phantom 85 on hyper but I'm waiting on replacement front mag wheel

There's alot of options for power gains, ALOT. In your opinion what are the best ways to increase power?

Also, running 40:1 rn

This.

I joke!

Honestly the basic engines are never going to be speed demons, without getting crazy into port timing, I'd say the most cost effective thing is a real expansion chamber and jet to match.

I don't believe in huge, fancy carbs, the Avenger and Phantom make great power with the cheap little bofang.

Oh and of course, the little bit of free power you get from cleaning the ports and making sure squish gap is in the money zone

I wouldn't go lower than 36t on the gearing.

Really, you shouldn't be below 32:1 especially if you give it the beans.

Many say 25:1 is the limit on the Phantom.

 

[DAMIEN1307]

Also, running 40:1 rn

How many times do I have to say this to everyone???...You run 20:1 for the first 300 miles, and then you can go 25:1 after that first 300 miles.

Using any less oil than this in any Phantom 85 motor will destroy it.