Tell me about exhausts...

The original 2-stroke Genuine scooter and its 4-stroke manual and automatic offspring

Moderator: Modern Buddy Staff

Post Reply
Anachronism
Member
Posts: 514
Joined: Sat Feb 21, 2009 10:56 am
Location: Colorado Springs

Tell me about exhausts...

Post by Anachronism »

Ok, so I'm trying to get an idea of what I want to upgrade the stock exhaust.

Lots of people go with the Sito+, but I'm not sure that it is a worthwhile performance upgrade.

Long term, I am probably going to put a cylinder kit on it, so I want a pipe that will work with a larger CC cylinder. This leads me to thinking I want an expansion chamber style pipe.

Thoughts?
User avatar
jmkjr72
Member
Posts: 783
Joined: Sat Jul 11, 2009 11:07 pm
Location: green bay wi
Contact:

Post by jmkjr72 »

i have yet to do any tuning on my stella but i can say that using an expasnion chamber pipe will give you more high end power but you wont make as much low end power and your power curve will be a narrow

meaning you will make a lot of power in a very small rpm range

another thing to consider is where you ride more and more areas are getting very sensitive to the noise coming from motorcycles and scooters and an expansion pipe sticks out and screams im an aftermarket pipe and more then likely not street leagel

another thing to consider is that with most if not all left hand pipes you loose your spare with some of the right handers it may be hard if not impossable to adjust your clutch with the pipe on if you need to

i my self am considering a few right handers the pinaso the malossi and the simonini i would love the hotwing but then 400 to 500 for a pipe is a large chunk of change
z 2008 zuma 50
olive 2008 setlla
1979 tomos
Image
User avatar
Kaos
Member
Posts: 4892
Joined: Mon May 19, 2008 5:39 pm
Location: Portland, OR

Re: Tell me about exhausts...

Post by Kaos »

Anachronism wrote:Ok, so I'm trying to get an idea of what I want to upgrade the stock exhaust.

Lots of people go with the Sito+, but I'm not sure that it is a worthwhile performance upgrade.

Long term, I am probably going to put a cylinder kit on it, so I want a pipe that will work with a larger CC cylinder. This leads me to thinking I want an expansion chamber style pipe.

Thoughts?
While its not my bike, just one I've ridden a few times, Vespa Portland's shop bike has a 177cc top end, a 26mm carb, and the Sito+ and it SCREAMS. Other than that it has no mods, its not actually even broken in yet. It will wheelie between shifts, and is a ton of fun to ride. It is a bit loud though.
User avatar
KRUSTYburger
Member
Posts: 3366
Joined: Sun Feb 10, 2008 1:54 am
Location: Pee-Cola, FL

Post by KRUSTYburger »

I was thinking of going sito+ on the P200. Mainly because the exhaust that's on there now is old & rusty. I got the old 24mm carb,
so I get along pretty sporty already. Any ideas what difference the sito+ will make? If it's gonna be real loud I might just get a stock
replacement. I just figured since I need one anyways I might as well upgrade. I dunno... :?:
Image
User avatar
Kaos
Member
Posts: 4892
Joined: Mon May 19, 2008 5:39 pm
Location: Portland, OR

Post by Kaos »

KRUSTYburger wrote:I was thinking of going sito+ on the P200. Mainly because the exhaust that's on there now is old & rusty. I got the old 24mm carb,
so I get along pretty sporty already. Any ideas what difference the sito+ will make? If it's gonna be real loud I might just get a stock
replacement. I just figured since I need one anyways I might as well upgrade. I dunno... :?:
Its slightly louder than the Prima on my Buddy. Its much more rat-a-tat-tat sounding. Being a two stroke and all...
User avatar
Frankie 2 Tone
Member
Posts: 141
Joined: Wed Jun 11, 2008 2:58 am
Location: Richmond, Va.
Contact:

Post by Frankie 2 Tone »

I have the Sito +............made a nice difference, and if I put a 177 kit, it will still handle it fine. You don't necessarily need a giant expansion chamber for such a small engine. The other thing I like, is the Sito + looks stock.
Kickin' it hard to the Rock Steady Beat!!!!!!!!
Sl,ut4
Member
Posts: 27
Joined: Thu Jan 10, 2008 6:58 pm
Location: SLC
Contact:

Post by Sl,ut4 »

1965 VBB 5 Port
Ported and matched Pinasco 184/ WORB5 race cut/ Boyesen Reeds/ Cut reed block/ Malossi 23-64 Upgear/ T5 Fourth/ Disk brake swap/ Ducatti CDI/ Quattrini Ignition/ S1's/ NGK/ B9HS.
01.5 S4 Sedan. Blk/Blk
STGII+ Drivin Slideways!
User avatar
cmac
Member
Posts: 118
Joined: Wed Jul 29, 2009 1:36 pm

Post by cmac »

It would be a no brainer if I could see what's written in the picture :)
User avatar
KRUSTYburger
Member
Posts: 3366
Joined: Sun Feb 10, 2008 1:54 am
Location: Pee-Cola, FL

Post by KRUSTYburger »

Image
Image
User avatar
cmac
Member
Posts: 118
Joined: Wed Jul 29, 2009 1:36 pm

Post by cmac »

Oo0o0o Nice! So 226/PM look to me like the winnaz!
User avatar
KRUSTYburger
Member
Posts: 3366
Joined: Sun Feb 10, 2008 1:54 am
Location: Pee-Cola, FL

Post by KRUSTYburger »

Actually looking at that chart I think I still prefer the Sito+. But of course it would also depend on price differences.
Image
User avatar
Kaos
Member
Posts: 4892
Joined: Mon May 19, 2008 5:39 pm
Location: Portland, OR

Post by Kaos »

But your chart is completely missing torque! You can't pick an exhaust based only on HP!
User avatar
KRUSTYburger
Member
Posts: 3366
Joined: Sun Feb 10, 2008 1:54 am
Location: Pee-Cola, FL

Post by KRUSTYburger »

Oooo... do you have a chart for torque? :bat:

or would that be too hard to measure?

Actually I don't even know what kind of scooter they used for that test. and it's different for different bikes right,
or is it pretty universal that each brand makes a pipe that has specific results for every model of scooter?
Image
User avatar
BuddyRaton
Scooter Dork
Posts: 3887
Joined: Sat Sep 09, 2006 10:08 pm
Location: Boca Raton, Florida
Contact:

Post by BuddyRaton »

They used a Stella for that test and went one mod at a time. I'll check that issue of Scoot! and see what they did first.

I think that changing to a Sito+ and upjetting is the best bang for your buck!

For my P200 I'm planning on a Sito+ and upjetting...that is it!

Expansion chambers rock! IF you get the rest of the tuning dialed in. The Malossi 177 kit is da bomb...IF you port the cases and the jug, dial in the jetting and the timing and dont lock it up on the way.

I have a 67 GT with an 83 p125e, ported and polished Malossi 177 top end, modified 24/24 carb/, custom expansion chamber, P200 tree, P200 clutch. This scooter is STUPID fast! It also siezed on me at about 65 mph :shock: I just got it put back together last night!

Nothing wrong with modifying a scooter. Just remember that you may be giving up some reliability.
"Things fall apart - it's scientific" - David Byrne
www.teamscootertrash.com

'06 Cream Buddy 125, 11 Blur 220, 13 BMW C 650 GT, 68 Vespa SS180, 64 Vespa GS MK II, 65 Lambretta TV 175, 67 Vespa GT, 64 Vespa 150 VBB 64 Vespa GL
Anachronism
Member
Posts: 514
Joined: Sat Feb 21, 2009 10:56 am
Location: Colorado Springs

Post by Anachronism »

I ordered the sito+. Doesn't look like there is a better pipe until you hit the ones with full expansion chambers for $500 like the ones at the top of the dyno above.
User avatar
BuddyRaton
Scooter Dork
Posts: 3887
Joined: Sat Sep 09, 2006 10:08 pm
Location: Boca Raton, Florida
Contact:

Post by BuddyRaton »

Keep us updated!
"Things fall apart - it's scientific" - David Byrne
www.teamscootertrash.com

'06 Cream Buddy 125, 11 Blur 220, 13 BMW C 650 GT, 68 Vespa SS180, 64 Vespa GS MK II, 65 Lambretta TV 175, 67 Vespa GT, 64 Vespa 150 VBB 64 Vespa GL
User avatar
irishtim
Member
Posts: 595
Joined: Mon Jun 18, 2007 4:11 am
Location: NE Ohio--RBC #12, EPSP #13, VCOA #2340

Post by irishtim »

BuddyRaton wrote: I think that changing to a Sito+ and upjetting is the best bang for your buck!

I concur. I ran a Sito+ on my '05 (with a sidecar) and have one on my '08. The stock-look is nice IMHO as well.
OH,PA,IN,WV,KY,TN,WI,MI,SC,ON,BDA
bcarter
Member
Posts: 20
Joined: Fri Oct 23, 2009 7:39 pm
Location: Decatur, GA

Post by bcarter »

I 'invited' my dealer to talk me into a sito plus today. Just went in for some normal maintenance and the subject came up and they looked in the back and saw one on the shelf, quote me a price and I bought it. Took them about 20 minutes to put it on and upjet it.

I had spent about 3 hours on my totally stock stella today running errands and had the usual problem getting up hills, sorta slow acceleration... very smooth, just not a lot of power. On the (long) way home from the shop, I had a lot of fun. Acceleration is a lot better, as is going uphills. The difference is not dramatic, I'm not popping wheelies or outracing cars, but there is definitely a lot more pep. The sound is nice too, not a lot louder, but with more of a popping noise that is cool :)

Anyway, not a lot of time or money invested in this upgrade, and I sure got a nice bang for the buck.
ObjectAgnosia
Member
Posts: 25
Joined: Fri Jul 17, 2009 1:23 am
Location: MA

Post by ObjectAgnosia »

Do you know what your jets are now by any chance?
bcarter
Member
Posts: 20
Joined: Fri Oct 23, 2009 7:39 pm
Location: Decatur, GA

Post by bcarter »

Yeah, they are all still stock except for the main jet. Stock was a 94 (I am fairly certain), but they put on a 98 yesterday afternoon. The discussed whether that was too rich and thought maybe a 96 would be better, so I'll pull the plug in a couple days.

The process of removing and installing the exhaust was easy, I could have done it myself and probably not taken much longer than they did, it is that straightforward. But I am new with all this and a little intimidated about the jetting, so I was happy to let them do it. Additionally, they said that if they installed everything, it wouldn't void my warranty. Kind of hard to say no to all that, lol!
bcarter
Member
Posts: 20
Joined: Fri Oct 23, 2009 7:39 pm
Location: Decatur, GA

Post by bcarter »

I spent another few hours on my stella today (post sito+ install) and I thought I'd post my mini-review:

The dealership told me that I wouldn't get much more top speed out of it, but I would get more power fairly evenly across all RPMs, but this isn't quite my experience with it. Stock, I could get my scooter to 50mph with a little bit of work probably get it higher than that, but it would take time, fourth gear acceleration was pretty bad. With the sito+, I was surprised to see myself at 50mph pretty quickly, with more throttle available. 55mph wasn't tough and cruising at 45-50mph felt a lot less strained. Before it felt like, at that speed, the engine was trying to hold me back a little, but with the new exhaust, it feels very stable with power leftover. Also, there are pretty steep hills where I ride and pre-sito+ I could not go up them in 4th and barely keep 30mph going up them. Now I can do it in fourth and easily maintain 40+mph if not slightly accelerate.

Also there is indeed more power across all RPMs which translates into quick acceleration. When the light turns green I can take off faster than most of the cars do, and actually I am getting to speed probably about as fast as I could in my honda civic. Again, not crazy fast, but good useful acceleration. What I do notice is that this power is pretty evenly distributed from low to high rpms, there is no spike in power. I can also accelerate to higher rpms before I have to shift.

The sito+ is, in my mind now, a no brainer upgrade. Cost me $180 total, including labor, which is really cheap when you think about it. It turned my fun little scooter into something much more usable, without being really loud. Again, the performance upgrade is not dramatic, but it is good useful power. I would totally do it again.
Shane Wilson
Member
Posts: 173
Joined: Mon Oct 08, 2007 8:51 pm
Location: Nashville, TN

Post by Shane Wilson »

Don't forget to do a plug chop just to be sure the jetting is right.

Really good performance can be a bit deceptive with 2 strokes.

They run REALLY great when they're lean but running lean leads to higher cylinder temps which causes seizure.

To do a plug chop, warm up your bike by riding for about five minutes or so.

Then get it up to the top of its range in third gear and hold it there for a few seconds.

Then cut the engine while pulling in the clutch.

Pull your plug. If you're in good shape you should see a light tan to deep mocha around the insulator of the plug.

Here's a site with some good plug photos:

http://www.dansmc.com/spark_plugs/spark ... talog.html
Anachronism
Member
Posts: 514
Joined: Sat Feb 21, 2009 10:56 am
Location: Colorado Springs

Post by Anachronism »

Reading piston wash is another good indication that your tune is correct, and gives you a better indication of actual cylinder temps.

Typically I do plug chops till the spark plug looks good, ride it 50 miles, and pop off the head to check piston wash.

Here is some info on checking piston wash.

http://www.bikemanperformance.com/tech_detail.php?ta=4
Valves are for wussies.
Shane Wilson
Member
Posts: 173
Joined: Mon Oct 08, 2007 8:51 pm
Location: Nashville, TN

Post by Shane Wilson »

Thanks for that.

I hadn't seen that before.

I've been considering a CHT gauge just to be on the safe side.
User avatar
BuddyRaton
Scooter Dork
Posts: 3887
Joined: Sat Sep 09, 2006 10:08 pm
Location: Boca Raton, Florida
Contact:

Post by BuddyRaton »

If you pull the head be sure to torque back on properly, run afewheat cycles and then retorque.
"Things fall apart - it's scientific" - David Byrne
www.teamscootertrash.com

'06 Cream Buddy 125, 11 Blur 220, 13 BMW C 650 GT, 68 Vespa SS180, 64 Vespa GS MK II, 65 Lambretta TV 175, 67 Vespa GT, 64 Vespa 150 VBB 64 Vespa GL
tony.appell
Member
Posts: 8
Joined: Sun Jan 10, 2010 3:31 am
Location: Scottsdale AZ

Thoughts on Exhaust choices

Post by tony.appell »

I have an 08 Stella, blew up the crank bearings at 4 K, (a known and documented weakness on the Indian motor, here is a post from just one site - "A weakness of the Stella is the small end bearing on the crank. With any of these kits, that bearing is more likely to fail. To protect the investment made in a cylinder kit, I recommend replacing the crank or even replacing the small end bearing. A Mazzuchelli crank- stock, cut, or full circle, is something that I also recommend.") I then put in a Mazzuchelli full circle crank, a Pollini 177 cylinder kit, piston and head, upjetted the stock carb (no need to buy a larger one, unless you plan on going over 65 mph, pm me for the details on that) de-restricted the air filter by replacing it with a T-5 version, changed the plug to a NGK B7HS (run NGK B8HS in the summer, when temps go over 90) and to the point of this discussion, put on a non-cat Sito pipe, NOT a Sito plus. If you want to annoy all of your neighbors, and all those with you on a group ride, and possibly cause yourself hearing damage, then go buy a Sito Plus pipe.

I now can run at an (actual) 63 mph, indicated 68 mph, all day long, even with 2 up on a flat road. No problems at all over 1700 miles later. Up from a measly 50 (actual) mph, from the stock scoot.
Post Reply