New Exhaust

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JJScoot
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New Exhaust

Post by JJScoot »

So I installed the scooterworks performance exhaust
https://www.scooterworks.com/Scooterwor ... gLfAPD_BwE

and the upjet recomendation.

Didnt really see any top end gains and the bike even was a little more sluggish. I was wondering if anyone thinks I should reinstall the original jet to see if that makes a difference. Someone mentioned to me that I might need to do something to the airbox to help it. Any ideas? It is still under warranty so before I start wrecking it, I might just put the stock jet and muffler back on.
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Stanza
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Post by Stanza »

Maybe do a plug chop first and get a read on it.
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az_slynch
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Post by az_slynch »

Your idle jet should be fine, but you'd have to upjet your main by one or two jet sizes.

Have you done anything to the intake side of the motor? You may want a less restrictive filter in order to see any real gain from an exhaust. Even swapping the stock foam out with a piece of UNI green or red foam can help, just be sure to lightly oil them.

Finally, may I suggest an alternative? Here's a pipe that will show better gains: https://www.treatland.tv/MLM-genuine-bu ... pe-495.htm

It's not much louder than stock and has a proper expansion chamber. The sidebleed looks odd, but it allows for a stronger reversion pulse and makes your engine feel a lot stronger in the mid-to upper rev range.


EDIT: According to the Scooter Lounge parts site, your stock main jet is a Keihin #75. The Scooterworks site recommends upjetting to a #80 for that pipe.
Last edited by az_slynch on Fri Aug 24, 2018 12:33 am, edited 2 times in total.
At what point does a hobby become an addiction? I'm uncertain, but after the twelfth scooter, it sorta feels like the latter...

Seriously...I've lost count...

Seven mopeds ...that's still manageable...
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Stanza
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Post by Stanza »

That MLM pipe is pretty much guaranteed to void the warranty though....not sure if that is important to you or not.
JJScoot
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Post by JJScoot »

Stanza wrote:That MLM pipe is pretty much guaranteed to void the warranty though....not sure if that is important to you or not.
Yeah, it's why I went with the scooterworks one- that and I don't like how loud the Prima is.

Would just breaking the snorkel off help at all? I wil check the plug to get a read. I'm looking for dark brown right?
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az_slynch
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Post by az_slynch »

Stanza wrote:That MLM pipe is pretty much guaranteed to void the warranty though....not sure if that is important to you or not.
I'd expect that swapping to an aftermarket exhaust shouldn't void the warranty under the Magnusson-Moss Act. The ones Scooterworks sells that "will void your warranty" are stated as such on their site; that empowers Scooterworks/Genuine to void the warranty under the terms of the Act. Unless they have documentation in the owners manual that specifies any aftermarket exhaust other than the specified "performance exhaust" voids your warranty, it might be harder for them to turn you down.

Now, goofing up the installation by not bolting the pipe on right or failing to install or replace the exhaust gasket could void it.

I guess Malossi carb changes get a pass. Odd, since they can do plenty of damage. The NCY manifold is nebulous at best with the *Off Road Use Only* tag.

The snorkel can be unscrewed from the air box. You'll get a slightly larger opening, but I would put some sort of mesh over it to keep critters or large debris out of the box.
Last edited by az_slynch on Fri Aug 24, 2018 12:35 am, edited 1 time in total.
At what point does a hobby become an addiction? I'm uncertain, but after the twelfth scooter, it sorta feels like the latter...

Seriously...I've lost count...

Seven mopeds ...that's still manageable...
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az_slynch
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Post by az_slynch »

JJScoot wrote:I don't like how loud the Prima is.
Some expansion chambers can be horribly loud. My buddy had an NCY chamber on his bugeye Zuma and it was obnoxious as all hell. Not a fan of loud pipes myself. Just so you can get an idea of sound level, here's a sidebleed MLM pipe on a 50cc Elite E:

https://www.youtube.com/watch?v=0_OsC7lk774

Not too loud compared to most expansion pipes.
At what point does a hobby become an addiction? I'm uncertain, but after the twelfth scooter, it sorta feels like the latter...

Seriously...I've lost count...

Seven mopeds ...that's still manageable...
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Stanza
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Post by Stanza »

az_slynch wrote:
Stanza wrote:That MLM pipe is pretty much guaranteed to void the warranty though....not sure if that is important to you or not.
I'd expect that swapping to an aftermarket exhaust shouldn't void the warranty under the Magnusson-Moss Act. The ones Scooterworks sells that "will void your warranty" are stated as such on their site; that empowers Scooterworks/Genuine to void the warranty under the terms of the Act. Unless they have documentation in the owners manual that specifies any aftermarket exhaust other than the specified "performance exhaust" voids your warranty, it might be harder for them to turn you down.

Now, goofing up the installation by not bolting the pipe on right or failing to install or replace the exhaust gasket could void it.

I guess Malossi carb changes get a pass. Odd, since they can do plenty of damage. The NCY manifold is nebulous at best with the *Off Road Use Only* tag.

The snorkel can be unscrewed from the air box. You'll get a slightly larger opening, but I would put some sort of mesh over it to keep critters or large debris out of the box.
I mean, my bike came with a warranty sheet and it's mentioned in the list of don't-do-that things

"Any Damage resulting from Modifications to the vehicle including but not limited to the use or performance/aftermarket parts"

Though I guess it'd depend on what was being asked for under warranty. A fancy pipe probably wouldn't be responsible for damage to your electrics, for example.
JJScoot
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Post by JJScoot »

I wont have time to mess with it until weds. Ill take a look at the plug- I dont want caramel anymore or do I? And then if that looks ok Ill go from there. Other than pulling off the snorkel, I dont want to do anything else to it. I checked my sliders and a few of them had a couple of worn down spots, but nothing terrible. I cleaned the variator and replaced them with some I had. I also have a yellow contra spring that I have never put in, I might try that out this weekend too. will it take mph off my top end?

I was pretty happy before the exhaust and up jet with my acceleration and just wanted a little more on the top end. I might end up just going back to stock. if nothing improves.
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az_slynch
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Post by az_slynch »

JJScoot wrote: Ill take a look at the plug- I dont want caramel anymore or do I? And then if that looks ok Ill go from there.
A mocha or caramel-colored plug is good. Ashy white indicates too lean, damp and black is too rich. Check the plug at idle and at various throttle settings. If you run it up to speed, hit the kill switch and coast to a stop, then pull and check the plug...if you let it come back to idle, you'll get a false plug reading for high throttle.
JJScoot wrote:Other than pulling off the snorkel, I dont want to do anything else to it. I checked my sliders and a few of them had a couple of worn down spots, but nothing terrible. I cleaned the variator and replaced them with some I had. I also have a yellow contra spring that I have never put in, I might try that out this weekend too. will it take mph off my top end?
Hard to say what the spring rating is without knowing the vendor. Different vendors use different color codes to identify the spring rating. If you can tell us what brand it is or where you bought it, we can determine if it's suitable.

At any rate, a stiffer contra spring alters the engine speed at which the transmission variates. Stiffer springs need more engine speed to be compressed. One pitfall is that just changing the spring can improve acceleration at the cost of top speed. In addition to higher revs, you may consider using heavier rollers to help overcome the spring and get the variator to actuate fully. Getting this to work well can sometimes tale a bit of fiddling, but I'll share a trick I found to guide the tuning.

Generally for a stock motor, I recommend going with the lowest level performance spring and adding rollers that are one gram heavier than stock. You can always mix three stock and three of the heavier rollers to create a smaller overall weight change. The ideal net gain is a bit sharper acceleration, as the variator stays in "low gear" longer, with the extra weight helping to mitigate the loss of top speed.

For really dialing it in, a cheap solution is to use a smartphone with a cycling app that can track and graph speed over time. I used to use My Tracks for Android, but it's n longer available. Whichever app you use, make sure it can record a ride and display a speed over time graph.

Get on your scoot, start a log with the app and accelerate from zero to top speed. Pull over and stop logging, then review the graph. When you look at the acceleration curve (speed over time), there's generally a dip in speed when the transmission variates. This data will help you dial in your transmission.

You can lighten the rollers to minimize the dip in the aceleration curve. If you have no dip, you can add weight to improve top speed, just make small changes until you start to see a small plateau in your acceleration curve.

Good luck with the tuning and share your findings, it's a bit of work but it'll be worth it when the scoot just accelerates cleanly from idle to WOT.
At what point does a hobby become an addiction? I'm uncertain, but after the twelfth scooter, it sorta feels like the latter...

Seriously...I've lost count...

Seven mopeds ...that's still manageable...
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wheelbender6
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Post by wheelbender6 »

I installed the Prima pipe on my buddy 125 and bigger jet. It does not void the warranty IF installed by a Genuine dealer.
I am happy with the Prima pipe, though performance increase is small.
It tried a few air box mods, but they all hurt performance a lot. I was told on another forum that the keihan clone carb on the Buddies will never run well with airbox mods or a pod filter.
2013 Buddy 125, Prima Pipe, #95 main jet, Orange CDI
JJScoot
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Post by JJScoot »

https://i.imgur.com/JaRxp41.jpg

Looks ok?

80 jet in there ( the recommended change withbthis exhaust)
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az_slynch
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Post by az_slynch »

JJScoot wrote:https://i.imgur.com/JaRxp41.jpg

Looks ok?

80 jet in there ( the recommended change with this exhaust)
Looks a touch rich, but not too far out off the mark. Did you pull the snorkel yet?
At what point does a hobby become an addiction? I'm uncertain, but after the twelfth scooter, it sorta feels like the latter...

Seriously...I've lost count...

Seven mopeds ...that's still manageable...
JJScoot
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Posts: 116
Joined: Sun Apr 23, 2017 11:42 pm

Post by JJScoot »

No I didnt. Mine doesnt seem to have one- Just kind of a cover/deflector. (2017 50) I tried running with it off, but didnt notice a difference. I went to put in an NCY 1500 compression spring I ordered a while ago and it was the wrong size. Will put in the correct one when it gets in. At this point, I think putting the stock jet and exhaust back on will be better than what I replaced them with.
JJScoot
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Post by JJScoot »

az_slynch wrote:
JJScoot wrote:https://i.imgur.com/JaRxp41.jpg

Looks ok?

80 jet in there ( the recommended change with this exhaust)
Looks a touch rich, but not too far out off the mark. Did you pull the snorkel yet?
Should I try putting the stock jet back in? Any harm in trying that?
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