Triple exhaust ports and what they are.

As you guys can tell, I don't come here much. But this is for Super Noober.
Before i start, everything can be found here. And yes, all i had was an 220 AC arc welder lol

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It is designed to peak at 8500RPM, port timing is 185 exhaust 118 transfers, with triples welded intake with extra large boyesens. Reeds have been upgraded to a blaster reed cage with power reeds. blaster carb(i have a 28-29mm round slide for it). Nicer than blaster carb at least.

It's flywheel is maybe 6 ounces less than the blaster, no counter balance shaft, auto clutch modded to stall out until maybe 3-4k RPM. Pod filter. Plenty of torque, Power band is very wide. The ass dyno says it pulls from 5k-8-9k? maybe more lol who knows.. I need a tach.

The pipe is designed to match the port job, and carb size is designed to match the flow rate at my target RPM.

At the dunes, with stock pipe, I passed Nathans blaster going up the dunes lol. Always fun to up-shift flying up dunes :)

That thing weighs to much for that engine though. 220lb on a 175cc engine? it needs to go on a diet.. I just don't know what can be removed lol

Oh yeah, the 3 wheeled side of the port job. http://www.3wheelerworld.com/showthread.php?127930-VIDEO!!-Drilling-triple-ports-in-a-cylinder-another-video-on-page-3/page3
 
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Math and program all the way. Designed it to match my port job as best as I could. I'm going to be building 1 for a blaster soon. Nate is going to port it and I'll be making the pipe for it.
 
LOL I'm with paulie. The look of the pipe just tickled me.

The real question is, how does it perform?

Edit: I re-read and saw 220V arc welder. You did REALLY well to get it as good as it is with that equipment. Obviously that's not optimal for building thin walled 2 stroke pipes but you have to use what you have!

If this is going to be a regular thing, Harbor Freight sells a scratch start DC only tig welder (about 90 amps max which would work really well for the thin wall pipes) for about $250. Spread the cost of that among a handful of handmade pipes and you could actually justify it. Get that and a small cone roller and you COULD make good looking pipes which would probably perform really well ( I only say could because I don't know you or your fab skills that well, some people have "it" and some people don't)
 
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rubber salt is my lil bro gabe and he passed me once when my clutch was slippn halfway through the gears and would finally hook then bog in too high of a gear but that thing does great for climbing, lots of bottom end/ also I have a 220v mig welder that he can use but i was busy and he wont wait ( cant blame him ).I personally couldn't have done as good of a job with his arc welder. I told him if he would grind about 80% of that weld down it would save a few pounds. The pipe is very functional though and preforms outstanding compared to stock. We both know his tryke is fast but my blaster will eat its lunch all day now that i fixed the clutch. Spywells wilderbeast of a quad was stolen recently and gabe gave up his first blaster to his friend to replace it. We are going to start hand building pipes to different specs and try our hand at pipe tuning. Once i have a pipe that is optimal and proven I will atempt to build a press and dies to stamp a few out. Gabe has several different pipe calculating programs and is good w numbers. this would be another thread all together:)
 
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The first pipe I ever built ('74 CR250) was brazed together.
Looked a heck of a lot better maybe, but didn't handle vibration very well.
It did make it easy to melt cones off and try different lengths.

The pipe was regular exhaust pipe with wedges cut out mainly by hacksaw to make cones, then hammered or hot formed to shape. The final version was the same material but gas and steel rod welded. It held up quite well but was moderately heavy. Since it went UNDER the bike that wasn't much of an issue.

He is experimenting and learning. First the book learning, then the hand tools.
Of course there are a lot of folks who just buy their speed parts like a big shopping list of bragging rights...
I figure I know who I'd learn more from in the end.

He will be smarter for the experience, the shoppers will still be chasing the herd.
 
best said:
The first pipe I ever built ('74 CR250) was brazed together.
Looked a heck of a lot better maybe, but didn't handle vibration very well.
It did make it easy to melt cones off and try different lengths.

The pipe was regular exhaust pipe with wedges cut out mainly by hacksaw to make cones, then hammered or hot formed to shape. The final version was the same material but gas and steel rod welded. It held up quite well but was moderately heavy. Since it went UNDER the bike that wasn't much of an issue.

He is experimenting and learning. First the book learning, then the hand tools.
Of course there are a lot of folks who just buy their speed parts like a big shopping list of bragging rights...
I figure I know who I'd learn more from in the end.

He will be smarter for the experience, the shoppers will still be chasing the herd.
Click to expand...

I hear you but my man needs to beg borrow or steal an angle grinder/flap wheel combo :p
 
When i was done with that pipe, i had Spywell pick it up then pick up the stock pipe.. The weight confused him - damn near the same!! lol

That 18guage steel sure is heavy for a pipe. Only advantage i see with it is it will retain the heat better, making the pipe more consistent with the power.

The pipe starts pulling way before the stock pipe, pulls longer, revs higher, and pulls MUCH MUCH harder. I did grind the welds out of the inside as I pieced it together. For a prototype, I was impressed how much better it performed compared to stock. The next pipe will be made with that mig welder of Nate's.

I like having bottom mid/top end power. But I have to have bottom end due to my auto clutch. So everything about my engine is designed with every component. Unlike having some one port it, then buying a top end pipe that bolts on, then a carb that is bigger/upgrade... Does the pipe match the port job? Does the carb match the rpm/displacement? Everything of mine is tuned to itself - it's an awesome little ride :)

Maybe I'll start a new thread and start inputting data and posting up some calculations made by my programs... for the next pipe - for reference when i go to build it.


***I did start with a CR125 pipe. After measuring everything, thebelly was the only part that was EXACT to what i needed, so I used that. I cheated, I'll admit to it lol. The next will be all me though.
 
Im always amazed at how this dead thread still gets hundreds of views a week :) Can we get some more of u guys to post some of your triple port related pics and vids? Im planning on attempting a built up weld on the outside of the triples to add more meat to port out on in a stock jug. me and gabe havent really got much work done this summer with the hottest ever summer in kansas with record # of days 100* +.It got up to 117* w ;like 98% humidity!!
 
This was the rough cut on the triples and exhaust port. Stock cylinder and sleeve with just a little tooling magic worked on it.

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I'll take better pics when I get it back from the machine shop probably tomorrow.
 
Parallax is coming into play there... the triples wrap far enough around the jug that they seem to "drop off". They're actually darn near the same height as the main. I did have a tiny slip with a burr I had to clean up in the main but it's less than 2 degrees difference which with the silly exhaust port duration I'm running won't matter much anyway.
 
Nice job!

Really important to make ports symmetrical or the piston ring pins work loose. the rings actually goes a little out in the port windows in the duration. and chamfer the edges too, all sharp edges scrape the oil of the piston and might snap a ring too.

I have been thinking about this myself a couple of times, lots of jugs has little material to cut. But as mentioned it is the first part of portopening that is most important so if the tunnel narrows down a little is not to bad.
 
What's the depth to cut to try to keep from busting through the outside? I really wanna try but I'm a lil skeert, lol! There just doesn't seem to be much meat there. Could someone give me a walk through?
 
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