3 into 1 pipe

[diablo]

do anyone in canada make a 3 into 1 pipe or would the closest be jemco in texas? love that sound, do they make any power above stock on a 750 k & how much do they cost? do anyone have measurements so a guy could make his own?

[tz375]

do anyone in canada make a 3 into 1 pipe or would the closest be jemco in texas? love that sound, do they make any power above stock on a 750 k & how much do they cost? do anyone have measurements so a guy could make his own?

No/yes
No/Call Jemco for pricing details &
No


One of the Kawasaki boys up there in ON is building a fully tapered 3 into 1 and we are all waiting to see how it turns out and how the performance looks. I don't think there's much else commercially available and no one yet seems to have cracked the 3 into 1 riddle in terms of decent design.

Two Stroke Wizard will generate a 3 into 1 design but doesn't tell you how or where to put the collector and when I input those numbers into MOTA it doesn't think they are very good, so something's up with that. Successful pipes seem to have short headers to minimize energy loss but gas flow favors long branches to equalize flow between branches. Maybe the key is to go for a pressure wave optimized design and try to minimize actual gas flow in reverse direction. Turns out that gasses do not always flow in the way you might expect them to.

My guess is that if you took three short headers and dumped them through a small volume collector into a big tube with a muffler, you wouldn't lose too much power but you would lose a ton of weight and would improve performance overall.

[diablo]

thanks for the reply, sound like alot of variables and very interesting. I have an old set of header pipes so i wanted to get an old 3 into 1 snowmobile chamber and try to build something if they are expensive. I know gas flow is important, i know sound wave works better in pressure, too much pressure will heat up pistons. I would want it to work as good as a stock pipe in any case so this could be alot of fun. I think it is the coolest sound so i will have to figure something. I'm buying a 750 k next month which is a torque motor so 3 into 1 should work good on it. what do they do for jetting and how far could i advance the timeing?
I gutted and rebuilt a rusted out set of bassanises last year for my 750 m and they work really good, a little noisey but, they work good.

[tz375]

Try to think of pressure waves, gas flow and back pressure as three different and barely related issues.

Pressure waves are what do the work of sucking the old gases out and stuffing new gas back in at the right time, sometime. They travel at the speed of sound which in a hot gas is something like 700 MPH

The gas itself travels much more slowly.

You can think of a river flowing slowly to the see and a ski boat blasts along creating small fast moving waves. Not a good analogy but you can see how waves travel in the water that is moving much slower.

In our case, the gas isn't moving much after the exhaust port closes, so velocity of gas = zero, but the waves are running back and forth. In reality, both are related to a degree, but hopefully you follow what I was getting at.

The next issue is so called back pressure. In a two stroke exhaust that's the bleed aka stinger that creates that pressure bleed off and that is critical to getting the pipe hot enough but not too hot.

Piston crown temps are impacted by pipe temps, but more so by what's going on in the combustion chamber where temperatures reach over 1000 degrees.

A well tuned motor when it's on the pipe will have a volumetric efficiency at its max, so the cylinder will be stuffed higher than at any other speed, so the effective compression at that point is very high, so we typically retard ignition timing on a tuned motor or one with a pipe that works. At low speeds cylinder filling is less effective, so we can use more advance. At higher engine speeds where the pipe is working, flame propagation is faster, so we need to light the fire later.

That's why you see guys with good pipes and higher compression taking a degree or more of timing out.

Running chambers without the muffler core and wadding tends to make it act as if the tail pipe is missing and that costs power. It might sound more powerful, but it would probably make more power with baffles repaired and fitted.

For the street, quiet is good.

[diablo]

yes very good analigy and tks i just learned something, i had made up baffles for my old pipes but, no wadding. i think it creates enough back pressure and it screames when it comes on the pipes, although not as loud as some barking harleys. I really would enjoy lower tone of a 3 into 1 and some grunt on the hills, for a little while anyway

[tz375]

One problem that we should keep in mind is that most of the 3 into 1 systems back in the day were really just a set of headers dumping into a large collector. The chamber part didn't do much of anything and was really just a fancy shaped silencer.

A collector will generate a strong wave pattern and long headers damp that wave out, so they sort of work at low revs. The big difference from OEM is weight.

of course 3 into 1 systems have been available for years on sleds and PWC and they perform way better than our OEM pipes and not as good as a set of 3 into 3 individual chambers. Places like SLP and AAEN have been selling Hi-Po single pipes for twins and triples for years and make good power up at 8200 or more in some cases. Not as much power as their own separate pipes but very respectable.

Maybe I'll have to have a go at designing a 3 into 1 one of these days. I think I have managed to secure the purchasing rights - option to buy a decent 3 into 1 so I'll have a baseline to test against. How I'll turn the idea into steel is less clear though. Maybe I'll go over to K land and see if Walms can roll me some cones.

[diablo]

kewl, did anyone ever dyno a 3 into 1? 8200 is probably higher than my k or l will be turning, must be a good single pipe they have designed.
started to get three cut off stock headers together into one last night, i am going to have to get them in a pipe bender to get the angles and clearence, this is going to be fun.
I want to run them into the middle bassani which is a slip on, that way i have three going into a proper size 750 chamber and see how it works. If it don't work well i can switch back to 3/3 and try to make a bigger chamber later with the 3 headers already made.
I think i may end up buying a new set of 3/3 chambers soon no matter how it goes, i need a new set of something

[tz375]

Lots of 3 into 1 pipes have found their way onto a dyno, but the only ones I have seen published are on sleds. that 8200 rpm figure was one I was looking at for a Polaris sled IIRC with a two into one or three into one system, I don't remember which. The point there was that they can be designed to work at higher revs than we might expect.

Stock headers are thick and heavy - almost as heavy as buying automotive bends. Any collector for a 3 into 1 will probably require welding in place to minimize flow and wave disruptions and the headers will probably end up much shorter than stock and not at all the same shape.

The simplest route is to buy a set of Jemco pipes. You could buy a set of their headers and flanges which I believe Jon Easton will sell if you ask him nicely.

If you end up making a pipe, I'd love to see the dyno results. there's not a lot of published information around.

Now for today's off the wall idea. Take your OEM pipes and grind the flanges down to split them in two. Remove the carbon and those odd noise muffling mesh panels in the front end and the baffle support plates which are spot welded to the inner half. Then compute the appropriate length for the reverse cones and stinger and weld those in place of the rear 2/3 of the stock pipe. repeat for the inners using the same angles and smaller diameters. Or weld the new back end inside the stock shell for a stealth look.

It's a lot of work and will not be quite as good as a set of Jemcos and will take as much welding and breathing air as it costs to buy a set, but who's counting.

[diablo]

this thing would not post
yes i had a yamaha sled pipe that went 2 into 2 with stingers coming out the side as opposed to the end into a single silencer, it reved to 8200 and worked very good.
i think that will be the way to go, get a set of jemcos and headers to make a three into one also.
Good idea for OEM's and those things do weigh a ton.
I'm not close to a dyno, i would like to try and make alot of noise for 60 HP
I notice some guys put the same jetting in all three carberators with aftermarket pipes, do they advance/retard the timeing to identical positions on all three cylinders also?

[tz375]

A set of Jemcos and mild porting will get you there and they don't require any welding or modification to fit. No fabrication etc.

With three pipes all cylinders should have the same jetting and the same ignition timing ( as each other).

[diablo]

yes jemcos and K & N filters are in order, i'm hopeing i don't have to tear the k motor down so the porting will have to wait.
I like the idea of keeping the timeing and jetting the same on all three cylinders although i see not everyone does that,

[stcyr]

My guess is that if you took three short headers and dumped them through a small volume collector into a big tube with a muffler, you wouldn't lose too much power but you would lose a ton of weight and would improve performance overall.

I agree. No diameter changes after the headers. The problem with the single chamber is that the same pulses that affect one cylinder positively are alway going to affect another negatively by pulling when it should be pushing or vice versa.

I like the idea of keeping the timeing and jetting the same on all three cylinders although i see not everyone does that,

If you're refering to timing specs with a dial gauge being different for center and outer cylinders, that's because the outer spark plug holes are angled so the probe will have to extend farther (3.64mm) than it does in the center hole (3.42mm) to achieve the same timing angle of 24° (or piston position of 3.42mm) BTDC for all cylinders. Unfortunately, the gauge's probe will typically have a fair amount of side play which makes it impossible to read correctly when sitting at an angle and carbon on the piston crowns make matters worse. The best way to set the outer cylinders timing would be to remove the tank and securely attach the gauge to the frame so the probe can move directly in line with the piston, then set them all at 3.42mm. Or just use a degree wheel.

Many bikes use leaner jetting for the hotter cylinders. The fuel gets used more efficiently so less is needed. Also, you won't need to have as many jets when rejetting.

[tz375]

I like the idea of keeping the timeing and jetting the same on all three cylinders although i see not everyone does that,

If you're refering to timing specs with a dial gauge being different for center and outer cylinders, that's because the outer spark plug holes are angled so the probe will have to extend farther (3.64mm) than it does in the center hole (3.42mm) to achieve the same timing angle of 24° (or piston position of 3.42mm) BTDC for all cylinders. Unfortunately, the gauge's probe will typically have a fair amount of side play which makes it impossible to read correctly when sitting at an angle and carbon on the piston crowns make matters worse. The best way to set the outer cylinders timing would be to remove the tank and securely attach the gauge to the frame so the probe can move directly in line with the piston, then set them all at 3.42mm. Or just use a degree wheel.
:[/quote]


Good catch. I always set timing with a dial gauge and the cylinder head off and lock it in. I forget that other people use points and time it up with the head in place.

[diablo]

Good to know about the three into a single chamber, that three into one thing is looking less atractive all the time, Sounds real nice but i need the power more than the sound.
Good to know that that ignition timeing is the same on all cylinders and the plug angles is what makes the difference.
I thought i read somewhere that the middle cylinder has a slightly smaller displacement and that was the difference in jetting. Correct me if i am wrong but i am afraid of running the middle cylinder lean, heating it up and burning it down.
Years ago a machineist friend of mine (kawi 9 guy) set the timeing with a dial gauge and it came out exactly on the marks, i have trusted the marks to be very close ever since.

[diablo]

There are a handful of guys on this site that represent a timeless wealth of knowledge on suzuki gt's, cheers to you because you would be missed. Seems like strokers of any brand are becomeing desireable these days. So glad i did not sell mine, looking foward to takeing a newly aquired 750 k to the frame next month and i am shure i will have a few questions for you .