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Shearer 2 into 1 Dune Pipe


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If some of you want the thread to die why are coming back on to repost ( or just bashing the pipe ) ?

 

Also why do you have to be so rude in your comments he must have put alot of time into developing this pipe

and what works for one person or setup might not work for the next.

 

Not everyone runs your pipe. If we were all the same what fun would that be.

 

I am sorry if this offends anyone. Lets encourage change not bash it we might all learn something.

We were trying to let the thead die because an idiot with horrible dyno tuning skills was the one trying to keep it alive. If this other fella that did the R&D knows what he is doing, then this thread would be better off to keep going with his input.

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  • 2 weeks later...

i'm curious why this pipe choice for a turbo? what does a 2-1 stand to gain on the setup? i don't agree with the "only one cylinder is open at a time" way of thinking at it. what happens in a 2-1 is that the pulses have to share a chamber and run into one-another, and basically, each cylindrr says to each-other, "get your own pipe" the way i understand it..... on traditional chambers, the pulse comes back to the cylinder at a preset time, as it gets near the right rpm, it begins entering the chamber a little too soon, which still creates stuffing, but some bleeds back out. then it hits the right time, and lastly, it gets kinda cut short once it exceeds the right time, and stuffing starts to decrease. this is the timing cycle. normally, the pulses can find a peaky harmony where stuffing can still work on a shared chmaber, but, normally creates an interference closely off that.....so i am really curious how this thing is made to be broad in description i really would like to see the power profile. judjing (a book by it's cover) the look, length, and girth of the pipe, i'd venture to assume that there is actually 2, or 3 timing conditions that enforce stuffing. first, a real low-timed pulse return on the traditional cycle. 2nd, a timing that allows the pulses to exchange cylinders, and 3rd, a duoble-cycle pulse. possible to have a 4th with double-cycle cylinder excange pulse, if interference can be dealt with. the "y" doesn't look verry nice for this, though....

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i'm curious why this pipe choice for a turbo? what does a 2-1 stand to gain on the setup? i don't agree with the "only one cylinder is open at a time" way of thinking at it. what happens in a 2-1 is that the pulses have to share a chamber and run into one-another, and basically, each cylindrr says to each-other, "get your own pipe" the way i understand it..... on traditional chambers, the pulse comes back to the cylinder at a preset time, as it gets near the right rpm, it begins entering the chamber a little too soon, which still creates stuffing, but some bleeds back out. then it hits the right time, and lastly, it gets kinda cut short once it exceeds the right time, and stuffing starts to decrease. this is the timing cycle. normally, the pulses can find a peaky harmony where stuffing can still work on a shared chmaber, but, normally creates an interference closely off that.....so i am really curious how this thing is made to be broad in description i really would like to see the power profile. judjing (a book by it's cover) the look, length, and girth of the pipe, i'd venture to assume that there is actually 2, or 3 timing conditions that enforce stuffing. first, a real low-timed pulse return on the traditional cycle. 2nd, a timing that allows the pulses to exchange cylinders, and 3rd, a duoble-cycle pulse. possible to have a 4th with double-cycle cylinder excange pulse, if interference can be dealt with. the "y" doesn't look verry nice for this, though....

 

You've been drinking again...haven't you?

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"only one cylinder at a time".... in my head (imagination land) i see the pulses getting messed up by eachother in one pipe.... but ive got a little bit of info that led me not to believe that there is no(major) interference between multiple pulses in one expanison chamber. of course we know that snowmobiles have been using 2 into 1 pipes for along time, and that dans turbo bike has set amazing records with twin scimitar with 2 into1 pipe, thats a little of the more obvious examples. during the testing of this pipe for shitz n giggles we put the pipe on a twin-gle crank bike(instead of the crank being 180degrees, both rods/pistons are at tdc and bdc at the same, firing both cylinders at the same time every 360degrees), the bike ran fine at idle but when reved it would bog horribly from both pistons firing at the same time and "double stuffing" the pipe. when the twin-gle bike had regular pipes(fmf) on it would rev like normal because both cylinders had there own pipe to fill, it was easy to see that if both pulses enter the(1) expansion chamber at the same time "double stuffing" the pipe the engine will not run anywhere near decent, on a normal 180degree crank there doesn't seem to be interfernce of pulse charges.

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Does anyone have links to Motofast? I checked on Dynoports website and its down right now , I am looking into the 2-1 intake and exhaust combo , I want to play with something different for awhile .

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Does anyone have links to Motofast? I checked on Dynoports website and its down right now , I am looking into the 2-1 intake and exhaust combo , I want to play with something different for awhile .

they dont make motofast pipes anymore. I would forget the 2 into 1 unless your running a turbo. There are way better low-mid pipes in a twin setup. All these guys that claim all these things about the pipe are flaky, and I have a hard time trusting what they say seeing how they wont prove it.

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  • 2 months later...

i think its cool..

 

what about the serval???? seems there isnt a pipe that really suited for it except the shear twins and the cpi's, other drag pipes.. what about a high flow low temp 2-1? i'm really interested in that one..

 

 

ok now on the other hand a same firing banshee motor !!!! i have been thinking of those in my head for along time didnt know what to expect what would happen i felt the sucker would probably just shake itself to death. wasnt sure if it would have more botom end and then just not rev as easily as the 180 firing now. ?

 

whats up with that?!?!!?

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  • 4 weeks later...

Can anyone direct me to more info and/or where they sell this Shearer 2 into 1?

 

 

I currently run the Dynoport 2 into 1 on my 98 Banshee (%100 stock motor internally - only mods are V-force 3's, 4 deg adv timing, reed spacers, .025" shaved stock head, K&N with ProDesign adaptor (airbox lid on in winter, off in summer), 290 main jets, and a Vito's high performance clutch with 3 HD springs to deal with the added power) and I use to run a Motofast 2 into 1 on my 87 Banshee (same basic mods as my 98, but the engine was also bored .060" over with Vito's Superstock pistons & Keihin 28mm PWK's - that setup worked very nicely, but the modified port timing on the pistons while making a good bit more topend, DEFINITELY weaked the bottom end which made a difference when manipulating the machine around on the sick hillclimbs!). This basic engine setup has worked out absolutely perfect for me and the riding I do with it in Western PA (Lot's of tight technical trails and very steep technical dirt and/or boney hill climbs).

 

But I do admit I would like a little more top end power just for the real long & loose high speed hill climbs, and I wouldn't mind being a little more competative in a drag race with those that have chosen to stick to twin pipes on their Banshee's. However I refuse to give up ANY of my Dynoport's valuable current off idle torque and linear Bottom end through mid range through topend pull just to gain this topend peak horsepower, so I'd also love to see the dyno tests and comparison of the Dynoport 2:1 against this Shearer 2:1!

 

 

incidently: My other thought process is to leave my Dynoport pipe and do the 4mm stroker crank which I'm figuring would maintain my current power curve layout while increasing the output across the board. This pipe would however be much easier (and probably cheaper!) if it is truly an improvement on Dynoport's design.

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  • 7 months later...
  • 2 years later...

 now the few i had are out and people like them

Get anymore feed back on the high volume 2 into 1?   Got any more made?   Anyone ever get any Dyno numbers or comparisons down on paper?

 

 

I tried the Pro Circuit twins just to prove to myself I wasn't missing something and I was right.   Sure they pull nice & hard once the rev's come up to the 4-5000 range, but off the pipe down in the 1000-4000 rpm range where I need to depend on them to make torque they are gutless just like most twins.  So it's back to my 2 into 1 Dynoport for now; but I'd love to make some more topend for wheelspeed on the big long coal hills without these modified port timing Vito's superstock pistons (or porting similar to them) which weakens a bit of my off idle torque unless I bring my compression up more, plus I'd possibly like to go to a 4 mil someday; so I'm still hoping this high volume Shearer 2 into 1 could be my answer!!!!!

Edited by gonecheenin
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