Anyone ever make a straight pipe for their Buddy 150?

eatworksleepdie · Post by **eatworksleepdie** » Thu Sep 22, 2011 9:36 pm

I have a friend who's a custom fabricator, and he does some amazing work. he put a 6 point roll cage in my 92 gti, all tig welded etc. looks great.. anyway..

has anyone ever had experience running a straight pipe on their scooter? I have a Black Jack 150 cc scoot.

the skinny is, I had a slight exhaust leak a while back (lost one of the exhaust nuts at the motor) and my butt dyno told me I had some HP gains.. well I want those ponys back, and thought about running a straight pipe.

think i need to worry about running the plug too hot? if i did do this, it'll allow the exhaust to exit that much faster, what i'm not sure about is if it's going to suck that much more air causing hotter temps.. should I also put a bigger jet in to dump more fuel?

anyone have any experience with this?

Tocsik · Post by **Tocsik** » Thu Sep 22, 2011 9:47 pm

Haven't heard of it on the Buddy yet but it sounds amazing on the 4T Stella:
viewtopic.php?t=19103&highlight=straight+pipe+stella

flatblackbuddy · Post by **flatblackbuddy** » Fri Sep 23, 2011 12:42 am

Tocsik wrote:Haven't heard of it on the Buddy yet but it sounds amazing on the 4T Stella:
viewtopic.php?t=19103&highlight=straight+pipe+stella

I would kill for my Buddy to sound like that. The louder the better. Do you know if that pipe is available for the Buddy?!

viney266 · Post by **viney266** » Fri Sep 23, 2011 2:07 am

I can't see the point in annoying THAT many people...Why do it?

Keep in mind, this is from a guy who has owned several Sound of Singles roadrace bikes that would make that seem quiet...very quiet...But I can't see being that loud on the street...

flatblackbuddy · Post by **flatblackbuddy** » Fri Sep 23, 2011 2:48 am

viney266 wrote:I can't see the point in annoying THAT many people...Why do it?

Keep in mind, this is from a guy who has owned several Sound of Singles roadrace bikes that would make that seem quiet...very quiet...But I can't see being that loud on the street...

Because I'm immature and I like loud noises.

All sarcasm aside, is there a QUALITY pipe out there that's louder than the prima but not a straight pipe? If only Two Brothers made a pipe for the Buddy. I actually do like that sound - not obnoxious unless you really wind it up, at which point you're acting obnoxious

neotrotsky · Post by **neotrotsky** » Fri Sep 23, 2011 5:42 am

On a 4-stroke motor, you need a certain level of backpressure. Sure, the Prima pipe may "look" like a straight pipe, but there is a level of restriction and baffling in it that produces the backpressure required for the engine. Remember that internal combustion engines are glorified air pumps, and you need the right pressures on either side of the intake and exhaust ports as well as inside the chamber to have everything work correctly. If the pressures are off and not balanced, you will lose performance and can damage your engine.

Also, any desrestriction you do on the exhaust side needs to be reflected on the intake side, and that's where the math gets sticky. You *could* run a straight pipe and a cheesecloth filter for your intake and mess around with the fuel and idle screws, but your engine wouldn't last long.

easy · Post by **easy** » Fri Sep 23, 2011 11:30 am

poc made a pipe for the chetak that was very lound and added abt 10 mph. I dont rember anyone talking abt engine damage caused by the pipe just your normal tuning and carb jet set up

eatworksleepdie · Post by **eatworksleepdie** » Fri Sep 23, 2011 1:30 pm

neotrotsky wrote:On a 4-stroke motor, you need a certain level of backpressure. Sure, the Prima pipe may "look" like a straight pipe, but there is a level of restriction and baffling in it that produces the backpressure required for the engine. Remember that internal combustion engines are glorified air pumps, and you need the right pressures on either side of the intake and exhaust ports as well as inside the chamber to have everything work correctly. If the pressures are off and not balanced, you will lose performance and can damage your engine.

Also, any desrestriction you do on the exhaust side needs to be reflected on the intake side, and that's where the math gets sticky. You *could* run a straight pipe and a cheesecloth filter for your intake and mess around with the fuel and idle screws, but your engine wouldn't last long.

cool! thanks!! this is exactly what I needed to confirm. I will probably rethink the idea. I don't want to have a straight pipe for the "loudness" factor, but more for the performance HP gains. We might have to put some baffles in there in order to give it some back pressure if its decided to do so.
When I rode/had my Ducati 748 in 2002, I had my pipes hollowed out by a guy who made a business out of it. The thing was loud as HELLLL.. way too loud, but it was also much much faster. Gave it probably about a 4-5 HP gain which is a lot on a bike that weighs 400 lbs. so if i could get a 2-3 hp gain on a bike that weighs 200 lbs, I'd be doing good!

My fab'ing buddy went to LTU, and re-designs suspension systems for the fun of it

go figure. here's a link to some of his work: http://btekfabrication.com/ (note: that's my trans when he put a Quaiffe LSD in my trans, in the header image, haha)

eatworksleepdie · Post by **eatworksleepdie** » Fri Sep 23, 2011 1:36 pm

and another thought.. Harleys are WAY LOUDER than that stella in the vid. I just had 3 douche's go by me last night, all on harleys, all were ridiculously loud. all had straight pipes and probably 1300cc (or so) bikes etc.. there's no way a little 12 hp 150 cc buddy would ever be as loud as those Harley dudes. just my .02

HowHH · Post by **HowHH** » Fri Sep 23, 2011 2:17 pm

eatworksleepdie wrote:and another thought.. Harleys are WAY LOUDER than that stella in the vid. I just had 3 douche's go by me last night, all on harleys, all were ridiculously loud. all had straight pipes and probably 1300cc (or so) bikes etc.. there's no way a little 12 hp 150 cc buddy would ever be as loud as those Harley dudes. just my .02

Yeah. Loudness is relative. I ride every so often with a few friends who have various cruisers. The Prima pipe doesn't stand a chance in that crowd.

Tocsik · Post by **Tocsik** » Fri Sep 23, 2011 2:36 pm

I sometimes think my Prima pipe seems too loud but then other factors skew the curve. Even sitting next to an idling tractor/trailer rig at a stop light drowns out my little Buddy.

Of course, the 150cc Buddy's are much louder under load than at idle but even pulling away at WOT gets drowned-out out by any muscle car, diesel Doge pick-em-up truck or any number of various tuner cars etc.

It's like marriage in the South. It's all relative.

(I'm allowed to say that cuz I'm originally from North Carolina)

viney266 · Post by **viney266** » Fri Sep 23, 2011 4:21 pm

Yeah, wouldn't it be nice if Two brothers, or Yoshimura made a good pipe? Now THAT is what I want to hear

flatblackbuddy · Post by **flatblackbuddy** » Fri Sep 23, 2011 5:53 pm

viney266 wrote:Yeah, wouldn't it be nice if Two brothers, or Yoshimura made a good pipe? Now THAT is what I want to hear

Speaking of Two Bothers...they make an exhaust for the Kymco Super8 150, which I believe utilizes the same GY6 motor as the buddy. Anyone knoe if this would work for our bikes? I'm sure that there would be some mounting issues that would need to be addressed, but would this work mechanically?

Here's the exhaust: http://www.twobros.com/cgi-bin/shopper? ... LL-09.html

bigbropgo · Post by **bigbropgo** » Fri Sep 23, 2011 7:50 pm

if your buddy can fab/weld then any gy6 pipe should work. a yosh would look amazing.

Tocsik · Post by **Tocsik** » Fri Sep 23, 2011 8:25 pm

There's a member in Guam with a custom pipe that looks similar to a Yoshimura (that "carbon fiber" look).

Good pics in this thread: viewtopic.php?t=14733&highlight=custom+pipe

Syd · Post by **Syd** » Fri Sep 23, 2011 8:41 pm

I can't find any pictures now, but I think Keys put a SuperTrapp on his Buddy that I remember looking pretty nice.

BuddyRaton · Post by **BuddyRaton** » Sat Sep 24, 2011 6:12 am

easy wrote:poc made a pipe for the chetak that was very lound and added abt 10 mph. I dont rember anyone talking abt engine damage caused by the pipe just your normal tuning and carb jet set up

I think POC also looked at making a performance pipe for the Buddy but realized that the Prima was going to be hard to beat as far as performance

easy · Post by **easy** » Sat Sep 24, 2011 5:06 pm

BuddyRaton wrote:
easy wrote:poc made a pipe for the chetak that was very lound and added abt 10 mph. I dont rember anyone talking abt engine damage caused by the pipe just your normal tuning and carb jet set up
I think POC also looked at making a performance pipe for the Buddy but realized that the Prima was going to be hard to beat as far as performance

I think I read that also but I'd be interested in getting a used 4t stella if they made a kit that'll enable a dependable 65 or so mph

neotrotsky · Post by **neotrotsky** » Sat Sep 24, 2011 10:23 pm

Also, the "loud pipes save lives" adage isn't as accurate as chopper guys and other motorcycle riders would like to think. The audio effect kicks in here, stating that sounds moves at a fixed rate depending on environmental conditions and SLP (sound pressure levels) measured in dB. The higher the dB, the louder the pipe. BUT, the sound is still traveling at the same speed (1,130fps @ 68 degrees, add 1.1 degree per 1 degree Fahrenheit of temperature increase). This means that the faster you go, the shorter the time the sounds has to move ahead. And, when traveling, the sound has less resistance going behind you because of the wake you and your bike make in the air creates a lower pressure zone (since sound is simply compression and rarefaction of air molecules and will naturally travel to the space with the least resistance first).

And, the exhaust is aimed BEHIND you, which means you are not projecting the full sound ahead of you. Some estimates are that only 20% of the sound produced by exhaust pipes is actually traveling ahead of the rider.

So, in truth, everyone to the side and back of you will REALLY hear that noise, but ahead of you? Not so much. Is it loud enough to make a difference? That's where the eternal debate is.

k1dude · Post by **k1dude** » Sat Sep 24, 2011 11:19 pm

I can't stand loud Harley's or sport bikes. I don't think it has to do with safety like they claim. I think it has to do with ego (Look-at-me! Look-at-me!).

Have you ever noticed people with loud bikes always try to situate themselves in the middle of a crowd and rev their bikes as much as possible without moving? And all they do is swivel their heads to see who is looking at them. That has nothing to do with performance or safety.

I actually love the sound of power, but not at the expense of ruining everyone else's peace. And I'll take a low rumbling 'thrummm' over 'wheeeeeeee' or 'braaaaaaap' anyday. I've yet to hear a Prima Pipe, but if it's as loud as a Harley with straight pipes, I want nothing to do with it.

But if a Prima or straight pipe on a Buddy or Stella gives it the sound of power without the obnoxious and intrusive decibel levels of other loud motorcycles, I'd be all for it.

Tocsik · Post by **Tocsik** » Sun Sep 25, 2011 12:56 am

k1dude wrote:I can't stand loud Harley's or sport bikes. I don't think it has to do with safety like they claim. I think it has to do with ego (Look-at-me! Look-at-me!).

Have you ever noticed people with loud bikes always try to situate themselves in the middle of a crowd and rev their bikes as much as possible without moving? And all they do is swivel their heads to see who is looking at them. That has nothing to do with performance or safety.

I actually love the sound of power, but not at the expense of ruining everyone else's peace. And I'll take a low rumbling 'thrummm' over 'wheeeeeeee' or 'braaaaaaap' anyday. I've yet to hear a Prima Pipe, but if it's as loud as a Harley with straight pipes, I want nothing to do with it.

But if a Prima or straight pipe on a Buddy or Stella gives it the sound of power without the obnoxious and intrusive decibel levels of other loud motorcycles, I'd be all for it.

Reminds me of a South Park episode....