Check it out

[Panhead5496]

Tempting to buy for the Warrior, would look sweet.

No way to add a muffler though, neighbors already complain about ONE straight pipe, imagine 2

http://www.ebay.com/itm/Mini-Bike-C...280698f&pid=100009&rk=1&rkt=1&sd=162552651574

 

[itsid]

would look cool on a mini bike I bet.

I don't think it'd be louder than a single straight pipe.

So I'd say, if you want it.. buy it!

'sid

 

[MiniMudder12]

Funny I just made dual pipes for my Baja warrior.

 

[Panhead5496]

would look cool on a mini bike I bet.

I don't think it'd be louder than a single straight pipe.

So I'd say, if you want it.. buy it!

'sid

Yeah it would look awesome it wouldn't be louder I don't think either...I was just making a dig at my cranky neighbors

Once the funds allow, I will for sure

Funny I just made dual pipes for my Baja warrior.

Pics or it didn't happen

 

[Bbqjoe]

Do it!!!!!

---------- Post added at 09:42 AM ---------- Previous post was at 09:41 AM ----------

Funny I just made dual pipes for my Baja warrior.

Did not!

 

[Panhead5496]

Do it!!!!!

---------- Post added at 09:42 AM ---------- Previous post was at 09:41 AM ----------



Did not!

I know I really need to

I attached some pics of what it looks like for those curious to see that didn't click the link.

 

[Panhead5496]

Love this part of the ad lol

"Remember this is not a Muffler, it make a lot of noise when it accelerates!
This is not legal for the streets!"

Come on now, does even LOOK like a muffler

 

[bob58o]

It looks sick! But my question is if you have two pipes that have a cross sectional area of 1 sq inch, does that behave the same as 1pipe with CSA of 2 sq inch. I really don't know. Does the exhaust gas slow down compared to a single pipe with CSA of 1 sq inch? Or stay the same because each pipe is still 1 sq inch. I should have taken fluid dynamics. Physics was a backup plan cause I didn't do well in Mechanical Engineering as a freshman. LOL

I love the way it looks, but I'm guessing there are better options for performance.
EDIT: unless one of the pipes is a pseudo-pipe just for show and not functional.

 

[Kartorbust]

It looks sick! But my question is if you have two pipes that have a cross sectional area of 1 sq inch, does that behave the same as 1pipe with CSA of 2 sq inch. I really don't know. Does the exhaust gas slow down compared to a single pipe with CSA of 1 sq inch? Or stay the same because each pipe is still 1 sq inch. I should have taken fluid dynamics. Physics was a backup plan cause I didn't do well in Mechanical Engineering as a freshman. LOL

I love the way it looks, but I'm guessing there are better options for performance.
EDIT: unless one of the pipes is a pseudo-pipe just for show and not functional.

Looks like both pipes work judging by the way they are cut at the beginning of the manifold. Outside of looks, almost seems pointless. Though a factory mini bike has exhaust similar.

---------- Post added at 08:02 PM ---------- Previous post was at 07:59 PM ----------

Dual exhaust on a single outlet is as pointless as dual exhaust on a turbo diesel...only one down pipe off the turbo and you won't get an equal amount of exhaust out of it.

 

[itsid]

....Dual exhaust on a single outlet is as pointless as dual exhaust on a turbo diesel...only one down pipe off the turbo and you won't get an equal amount of exhaust out of it.

..he said, hopped in his twin turbo and rushed off...
'sid

 

[Panhead5496]

It looks sick! But my question is if you have two pipes that have a cross sectional area of 1 sq inch, does that behave the same as 1pipe with CSA of 2 sq inch. I really don't know. Does the exhaust gas slow down compared to a single pipe with CSA of 1 sq inch? Or stay the same because each pipe is still 1 sq inch. I should have taken fluid dynamics. Physics was a backup plan cause I didn't do well in Mechanical Engineering as a freshman. LOL

I love the way it looks, but I'm guessing there are better options for performance.
EDIT: unless one of the pipes is a pseudo-pipe just for show and not functional.

Yes it looks very sick

Can you repeat that in English please

Lol just kidding, but I have no idea about that stuff. I'm sure there are better performance options, but who cares when it looks that cool!

They both definitely are outlet pipes it seems

Looks like both pipes work judging by the way they are cut at the beginning of the manifold. Outside of looks, almost seems pointless. Though a factory mini bike has exhaust similar.

---------- Post added at 08:02 PM ---------- Previous post was at 07:59 PM ----------

Dual exhaust on a single outlet is as pointless as dual exhaust on a turbo diesel...only one down pipe off the turbo and you won't get an equal amount of exhaust out of it.

I think they both work too.

Now that is one nice looking mini bike! What is it? I wouldn't mind one of those

This guy has lots of cool stuff http://www.ebay.com/usr/andrei-x?_trksid=p2047675.l2559

This would be SWEET looking on a cart http://www.ebay.com/itm/Ceramic-Coa...762458?hash=item3f7f8b1ada:g:q4gAAOSwT5xZRcL~

 

[Kartorbust]

It's a Little BadA mini chopper. Can't use the whole name because of the language used with it.

 

[bob58o]

but who cares when it looks that cool!

HI, My name is Bob. Bob cares.

The only reason I wondered about the dual pipes is because I've been looking over exhaust options for a 212 predator.

Math is more universal than English so I'll speak in math. LOL

212cc = 12.94 cubic inches
3600 RPM

Cross Sectional Area of Exhaust Pipe = Displacement x RPM / 88,200
3.14159 x r^2 = 12.94 x 3600 / 88,200
3.14159 x r^2 = 46,584 / 88,200
3.14159 x r^2 = 0.528
r^2 = 0.168
r = 0.41"

So a 0.41" Radius here means a 0.82" Inner Diameter Exhaust Pipe
a 1" pipe with 0.065" wall thickness has a 0.87" Inner Diameter

0.5945 = 12.94 x RPM /88,200
52,432 = 12.94 x RPM
RPM = 4,052
So according to this formula, a 1" exhaust pipe with 0.065" wall thickness is tuned for just over 4k RPM.

Just felt like sharing.

 

[ezcome-ezgo]

Solid dose of GAB there. Equal amounts of fluid, one amount moving through a 1" pipe, one amount moving through 2-1" pipes. All else being equal, the amount moving through the 1" pipe will have a higher velocity.

 

[Panhead5496]

It's a Little BadA mini chopper. Can't use the whole name because of the language used with it.

Oh I gotcaha. I've seen those, awesome looking bikes!


@Bob I am going to have to take your word for it, all that sounded like "blah blah, add blah blah to blah, divide by blah, get blah blah"

You are smart, very impressive stuff

 

[bob58o]

I'm not that smart. Formulas I share are plagiarized from the internet. I'm not deriving any of these formulas. Algebra and trig I remember because it is useful for everyday stuff. I took three Calc classes and 2 differential equations classes in college and barely remember a lick of it. Haven't had to used calculus since school. There are calculators and programs for that stuff.

Gear ratios and max speed questions come up often so I try to to show people how to calculate it themselves. The exhaust stuff... I just happened to be looking at for my own engine.

I do spend a lot of time making sure all the pieces fit together correctly. Like making sure gear ratio, tire size, camshaft, valve size, carb size, exhaust size, valve springs, clutch engagement,.... all fit together for the type of driving I plan on doing.

 

[Panhead5496]

Well regardless, you still can use the formulas!

I took one algebra class and it about killed me lol. I suck at math

I bet your stuff runs very well

 

[Noseoil]

Bob, thanks for the math lesson, but I think you've left out the stuff about the length of the pipe having something to do with the rpm range it works at. Just sayin'....

 

[Hellion]

Nice product but I offer an appeal to the unnamed manufacturer to please make some in chrome!

Be delighted to have some glitz and be able to turn it those wonderful rainbow colors from heat discoloration. I think that's desirable.

 

[bob58o]

Bob, thanks for the math lesson, but I think you've left out the stuff about the length of the pipe having something to do with the rpm range it works at. Just sayin'....

The formulas for exhaust length involve wave tuning. Need to know the the cam event timing to tune for a specific RPM (exhaust valve opening).

A pressure (or negative pressure) wave travels a certain distance at certain speed. You can use those numbers to solve for time. Adjust the length so that the negative pressure wave starts at the valve when the exhaust valve opens, moves to the end of the exhaust, and comes back to the head at the time you want it to (during the cam overlap). If timed correctly (meaning the right length pipe is used), the negative pressure will help pull out any remaining exhaust gasses and help pull air/fuel in through the intake. The length of the pipe determines at what RPM this effect is optimized.

In general, the the length doesn't change the RPM where the peak is. Shorter pipes will fatten up the area under the curve post peak HP.
Longer pipes will fatten up the area under the curve pre peak HP.


I feel like I'm being baited to use Calculus. I won't do it. LOL


Longer pipes means it takes a longer time for the wave to travel back and forth in the exhaust pipe. This helps the engine scavenge air better at low rpms when the piston is moving slower and there is more time between the events.

Shorter pipes means it takes less time for the wave to travel back and forth. This helps at higher RPM when the piston travels faster and the time between events is shorter.

Please excuse the rough drawing.