Triple exhaust ports and what they are.

[sicivicdude]

It really looks like you were able to get a good little pathway down beside the sleeve. From Ken's cutaway it doesn't look like there's a bunch of material there to work with but your little tube looks fair size.

I think I'm going to order a right angle pencil grinder to do this sort of thing with. I have a dremel 575 attachment I can't shove down into my cylinder straight enough to keep the burr from walking. The pencil grinder is the trick and I want one BAD.

 

[blasterfreek30]

It really looks like you were able to get a good little pathway down beside the sleeve. From Ken's cutaway it doesn't look like there's a bunch of material there to work with but your little tube looks fair size.

I think I'm going to order a right angle pencil grinder to do this sort of thing with. I have a dremel 575 attachment I can't shove down into my cylinder straight enough to keep the burr from walking. The pencil grinder is the trick and I want one BAD.

there is quite abit of material there, its just getting the nerves up to keep hogging it out without blowing out the sides lol...as far as the dremmel with the right angle, yes it will not sit in there square to the sleeve and u have to hold it real steady with a brand new bit when going thru the sleeve cause like u said it will jump and walk but once ur thru the tough part is over...we just start with a small hole and keep reaming it out and shaping it...of course the snake tool attach. helps alot too with beveling the sides

 

[sicivicdude]

Got more nerve than I, after I walked a burr about the fifth time on a junk cylinder.... I hung that stuff up and come inside to research tools more.

So how thin is that area you are hogging in there?

I think part of the problem with hogging a whole lot is the exhaust port timing you're working with too. Stock height exhaust port might be down there in a fatter area of the cylinder. Raised exhaust port height might get a bunch thinner.

 

[StrokedTater244]

I think I'm going to order a right angle pencil grinder to do this sort of thing with. I have a dremel 575 attachment I can't shove down into my cylinder straight enough to keep the burr from walking. The pencil grinder is the trick and I want one BAD.

you can get it all with a #225 I:I

sorry maybe not..but its worth a shot.. you can 99% of the transfers with one anyway.

 

[sicivicdude]

I have a flex shaft drive but it won't allow you to turn straight into the transfers (or cut straight into the sleeve as is the case with the triple ports)

I was looking at a right angle pencil grinder as an alternative to purchasing a porting kit from CC specialties... they are MIGHTY proud of their stuff.

I understand it's top notch equipment and if I were doing more of this type of thing, I might consider it but I don't need a right angle head THAT bad.

 

[best]

Interesting thread guys!

For what it is worth, the KTM 125/200 uses 3 port exactly as you are building here, only with a twist.
They have a tube inside that port and twist it to open or close the side ports with the powervalve.
The two side gears are tubes with a hole in the side that matches up with the hole into the exhaust port.
They are closed at low rpm and open by a centrifugal governor working against a spring.

The diameter is still quite small, at about 8mm.
(the small upper holes are the powervalve pivot, the top one its actuator)

 

[Spywell]

I am really close friends with nasty Nathan and Rubbersalt. We are having this little competition between Nathan and I for the fastest quad. I have a big, heavy Polaris 400 completely modded out and Nathan has his new blaster that is pretty close. We havn't raced them yet and I am pretty sure I will win but the reason I posted this and gave you all a little background is because I see what these blasters become. I am shocked that there are so many skeptics and although it might sound like blasphemy on these forums, blasters are only good to be hopped up. Yes I said it, stock blasters suck, so believe me when I say that porting these blasters with tripples brings them to life and honestly opened my eyes to a wonderful bike that can be cheaply modified for huge gains. I would never own a Stock Blaster!

Hopefully my eyewitness account of the power gains is enough to persuade the naysayers! Have a great day everyone, your forums are pretty cool. If I ever purchase a blaster I will be sure to frequent this place!

 

[99LRDblaster]

I see this as working, but at what cost?......and does that cost outweigh losses?

The way I see it, with porting and then triple exhausts, you do eliminate exhaust gases quicker and more completely. However, with a portion of the fresh intake charges being mixed with exhaust gases, much of the fresh intake charge would be lost in the extra volume of the triple exhaust ports.

Example(random #s):
-Conventional porting loses 8% of fresh intake charge as piston closes the exhaust port going towards TDC.
-Triple exhaust porting loses 12% of fresh intake charge as piston closes the exhaust port going towards TDC due to extra volume of triple exhaust port allowing more space for RETURNING fresh intake charge from pipe to remain.

I suppose that's my biggest question. Now if you could somehow add in valves similar to reed petals to open and close the triple ports(where they meet the main exhaust port), I could see it being even more beneficial.......however that's much easier said than done concerning the temps it would have to endure and judging by the amount of pressure/vacuum draw you would need. Another way you could maybe improve backflow slightly is to put a lip on the entrance of the triple exhaust ports into the main exhaust port so that it flows just as well during the exhaust phase, but when the intake charge is returned the air flow flows more over the lip to help direct it back through the main exhaust port and back into the cylinder.

 

[sicivicdude]

The blaster's suffer from exhaust duration problems.

More like they only clean 88% of the last stroke's burnt gas out stock. With triples they clean 92%. (same numbers you use but more of a corrected example)

 

[99LRDblaster]

The blaster's suffer from exhaust duration problems.

More like they only clean 88% of the last stroke's burnt gas out stock. With triples they clean 92%. (same numbers you use but more of a corrected example)

Yea I get that much. My only concern is how much of the fresh intake from the part where the transfers and exhaust ports are open at the same time would be lost? If more of the fresh intake is lost, I would think you would see a decrease in bottom end power.

This is probably one of the biggest downfalls of 2 strokes in that they don't have true valves to precisely control the flows of the intake and exhaust even with powervalves.

 

[sicivicdude]

It's true that's the downfall to conventional 2 strokes.

You would need to port the cylinder to take advantage of the rpm the pipe is tuned for. At certain RPM's expansion chambers are efficient at stuffing the fresh charge back into the cylinder before the exhaust port closes.

 

[99LRDblaster]

It's true that's the downfall to conventional 2 strokes.

You would need to port the cylinder to take advantage of the rpm the pipe is tuned for. At certain RPM's expansion chambers are efficient at stuffing the fresh charge back into the cylinder before the exhaust port closes.

Exactly what I was thinking too. That has to be a biotch and a half to do though without flow equipment.

 

[sicivicdude]

Play with pipe and porting long enough with enough trial and error and it would become like a second nature.

Even if the port timing isn't absolutely perfect for the pipe and carburetor setup, it's still better than stock timing so they just play until they figure it out.

 

[99LRDblaster]

Play with pipe and porting long enough with enough trial and error and it would become like a second nature.

Even if the port timing isn't absolutely perfect for the pipe and carburetor setup, it's still better than stock timing so they just play until they figure it out.

Maybe even dyno tune.

 

[super noober]

I am really close friends with nasty Nathan and Rubbersalt. We are having this little competition between Nathan and I for the fastest quad. I have a big, heavy Polaris 400 completely modded out and Nathan has his new blaster that is pretty close. We havn't raced them yet and I am pretty sure I will win but the reason I posted this and gave you all a little background is because I see what these blasters become. I am shocked that there are so many skeptics and although it might sound like blasphemy on these forums, blasters are only good to be hopped up. Yes I said it, stock blasters suck, so believe me when I say that porting these blasters with tripples brings them to life and honestly opened my eyes to a wonderful bike that can be cheaply modified for huge gains. I would never own a Stock Blaster!

Hopefully my eyewitness account of the power gains is enough to persuade the naysayers! Have a great day everyone, your forums are pretty cool. If I ever purchase a blaster I will be sure to frequent this place!

come get some biotch hahahahahaha

 

[N8tsNastyBlasty]

We'll see how it goes down when we hit the sand spywell. Dont forget i sold that wilderbeast of a quad to u for $60 and i still only have half the money in my ride that you do. After i sell my first build if it didnt kick ur ass them im sure a stroked out methanol burnin nos breathin one will on my next one! like the powervalved ktm pics. here's a vid of me drilling the initial holes for my bros triple ported yt175!!!

 

[Spywell]

i see this as working, but at what cost?......and does that cost outweigh losses?

The way i see it, with porting and then triple exhausts, you do eliminate exhaust gases quicker and more completely. However, with a portion of the fresh intake charges being mixed with exhaust gases, much of the fresh intake charge would be lost in the extra volume of the triple exhaust ports.

Example(random #s):
-conventional porting loses 8% of fresh intake charge as piston closes the exhaust port going towards tdc.
-triple exhaust porting loses 12% of fresh intake charge as piston closes the exhaust port going towards tdc due to extra volume of triple exhaust port allowing more space for returning fresh intake charge from pipe to remain.

I suppose that's my biggest question. Now if you could somehow add in valves similar to reed petals to open and close the triple ports(where they meet the main exhaust port), i could see it being even more beneficial.......however that's much easier said than done concerning the temps it would have to endure and judging by the amount of pressure/vacuum draw you would need. Another way you could maybe improve backflow slightly is to put a lip on the entrance of the triple exhaust ports into the main exhaust port so that it flows just as well during the exhaust phase, but when the intake charge is returned the air flow flows more over the lip to help direct it back through the main exhaust port and back into the cylinder.

I have been trying to send this all day but the forum keeps giving me errors when I preview or submit the message.
Original message:
Maybe you should think about it a little more. Did you notice the KTM picture above and how it closes at low rpms and opens at high rpms? The purpose of the triple ports is to remove more exhaust gas while creating more vacuum which pulls more gasses into the cylinder. I don't doubt your logic but I think it would only apply at low rpms which is why the KTM closes. At high rpms on a tuned pipe in theory you should gain a much higher charge.

Two strokes are made to be in their powerband and it's really silly to think you will be idling a 2t around all day lol. In other words, I don't think your analogy would prove itself while the engine is at high revs.

 

[Spywell]

We'll see how it goes down when we hit the sand spywell. Dont forget i sold that wilderbeast of a quad to u for $60 and i still only have half the money in my ride that you do. After i sell my first build if it didnt kick ur ass them im sure a stroked out methanol burnin nos breathin one will on my next one! like the powervalved ktm pics. here's a vid of me drilling the initial holes for my bros triple ported yt175!!!YouTube - Triple Port exhaust YT175 / Blaster

Lol "N8t" with my clutching tuned in correctly I think it will be very interesting to see a high horsepower beast with cvt go up against a light and nimble blaster. I have everything tuned for my powerband and finally my CVT is as well which means I will be in my powerband in two seconds and stay there the whole time

BTW the only thing left of the bike you sold me is the plastics and the transmission. LOL the transmission is only there because my new 4x4 tranny snapped the 3/4 inch hardened steel output shaft under the power of my engine! Serious, the whole frame, my spare engine, broken tranny, wheels, etc is all in your shed right now lol!

Also, now that I got you and your brother that argon bottle to weld aluminum with. I have been considering having you weld in my waterjackets to put triples in my 400 cylinder, that would be wild...

 

[slickerthanyou]

here ya go slickster...we have added them to all the blastys, and if this triple job runs well enough, they will all get them too

and a few more of the triples

Oh great, now i'll have even a harder time keepin up with you, Batt and Joe!

Maybe even dyno tune.

Um-bwaaaaaaahhhhhhhhhaaaaaaaaaaaaaaaaaaaaaa!

We'll see how it goes down when we hit the sand spywell. Dont forget i sold that wilderbeast of a quad to u for $60 and i still only have half the money in my ride that you do. After i sell my first build if it didnt kick ur ass them im sure a stroked out methanol burnin nos breathin one will on my next one! like the powervalved ktm pics. here's a vid of me drilling the initial holes for my bros triple ported yt175!!!YouTube - Triple Port exhaust YT175 / Blaster

Great vid! I am a visualist and that was perfect. Greenage your way!

 

[Awk08]

Oh great, now i'll have even a harder time keepin up with you, Batt and Joe!

joe doesnt have any of these extra ports, hmmmmm..............
wonder why he's so fast on the trails ??????