Advice on jetting?

Hwarang · Post by **Hwarang** » Mon Apr 30, 2012 5:50 pm

So, I think I want to toss that prima pipe on my Buddy 125. I see that if I order the kit, it comes with three jets (90, 95, 100).

I'm a bit of a noob ... mechanically. I understand I need to re-jet. I don't know which one of those to put on, though (or why).

Can someone explain (or link) some info? I tried googlin' and mooglin' but I didn't find a suitable explanation. I figure you cats might be able to just tell me which to use ... or teach a man to fish, so to speak.

Any advice is most appreciated.
Thanks!
-B

k1dude · Post by **k1dude** » Mon Apr 30, 2012 5:57 pm

I think which one you use is just trial and error, otherwise, they would just give you one jet to replace the stock jet.

I would personally take a look at your spark plug - it should be a nice even mocha color. Then I would throw on the Prima pipe with your stock jet, After a couple hundred miles, look at your plug again. If it still looks like it did before, you're fine. If it looks ashen, you're too lean, so throw on the 95. If it looks too black, throw on the 90. I think the stock jet is a 92. I think most people wind up using the 95.

I've never done the Prima pipe yet, so I'm talking out my arse. But that's how I believe the proceedure goes according to what I've read.

Hwarang · Post by **Hwarang** » Mon Apr 30, 2012 6:03 pm

k1dude wrote:I think which one you use is just trial and error, otherwise, they would just give you one jet to replace the stock jet.

I would personally take a look at your spark plug - it should be a nice even mocha color. Then I would throw on the Prima pipe with your stock jet, After a couple hundred miles, look at your plug again. If it still looks like it did before, you're fine. If it looks ashen, you're too lean, so throw on the 95. If it looks too black, throw on the 90. I think the stock jet is a 92. I think most people wind up using the 95.

I've never done the Prima pipe yet, so I'm talking out my arse. But that's how I believe the proceedure goes according to what I've read.

That's fine, I'll take arse-talk at this point.

So, if I can infer from your post ... putting the prima pipe on changes the exhaust characteristics in such a way that the engine will run a little more lean?

So, I am looking to put a jet on that counteracts that?

k1dude · Post by **k1dude** » Mon Apr 30, 2012 6:10 pm

Yes. The Prima pipe usually leans out the mixture a little. USUALLY! I would imagine there are Buddy's out there that ran rich after the installation just to make me look like an idiot. I suspect that's why they give you a 90. But you'll notice even in the kit, they favor giving you more jets to enrich (2) rather than leaning out (1). And the bias is 2 leaner and 8 richer than stock. So you can assume most people are running too lean after the Prima pipe install.

Hwarang · Post by **Hwarang** » Mon Apr 30, 2012 6:47 pm

Ok, that makes sense. Thanks!

tenshi · Post by **tenshi** » Mon Apr 30, 2012 8:08 pm

Hwarang, I just did what your proposing and your really not going to get much improvement if any. All you'll end up with is scoot that gives you 10 mpg less. But if you want to know what my shop did, and they've done it several times and found that this optimal for my elevation, here it is. They took the #92 jet out and put the #95 jet in. Changed the air fuel mixture from 1 1/2 turns out to 2 1/2 turns out. This works fine for sea level up to 2500 ft, then it starts getting to rich. By the time you make it up to 4,000 your top speed is 35smph. Hope my info helps.

tenshi · Post by **tenshi** » Mon Apr 30, 2012 8:12 pm

oh you're not going to gain any top end, but the bike will feel like its running smoother and will run a few degrees cooler.

k1dude · Post by **k1dude** » Mon Apr 30, 2012 8:37 pm

tenshi wrote:I just did what your proposing and your really not going to get much improvement if any. All you'll end up with is scoot that gives you 10 mpg less.

Interesting. I've always thought of getting the stage 1 kit. Now, not so much. Thanks for the insight. I guess I'll never get to hear that Prima pipe sound everyone likes so much.

tenshi · Post by **tenshi** » Mon Apr 30, 2012 8:40 pm

don't get me wrong. I love the sound of the Prima pipe, I'll just probably put the #92 back in to get my mpg back.

Hwarang · Post by **Hwarang** » Mon Apr 30, 2012 8:52 pm

tenshi wrote:Hwarang, I just did what your proposing and your really not going to get much improvement if any. All you'll end up with is scoot that gives you 10 mpg less. But if you want to know what my shop did, and they've done it several times and found that this optimal for my elevation, here it is. They took the #92 jet out and put the #95 jet in. Changed the air fuel mixture from 1 1/2 turns out to 2 1/2 turns out. This works fine for sea level up to 2500 ft, then it starts getting to rich. By the time you make it up to 4,000 your top speed is 35smph. Hope my info helps.

That's ok, bud! This is a cosmetic mod. I want the cooler looking and sounding pipe. I'm just asking about the jets because I don't want to accidentally run my scoot too rich or lean. A friend is going to help me with a few other minor performance mods (like better rollers or sliders, etc). Overall I'm not looking to squeeze more performance out of my Buddy (otherwise I'd buy a170i). It's basically good enough as-is, for what I do with it.

I just want it to look sweet and stay in good condition!

tenshi · Post by **tenshi** » Mon Apr 30, 2012 11:41 pm

If you really want to feel a difference in the way the Buddy rides change the tires to Zippys, S1s or even better Heidenaus. Second on the list would be the NCY transmission kit.

Hwarang · Post by **Hwarang** » Tue May 01, 2012 1:19 am

tenshi wrote:If you really want to feel a difference in the way the Buddy rides change the tires to Zippys, S1s or even better Heidenaus. Second on the list would be the NCY transmission kit.

I dinged my rim (deep as a quarter) on a wicked pot hole, and my rear tire is now a "slick" - so I was, in fact, browsing the Heidenau website ...

tenshi · Post by **tenshi** » Tue May 01, 2012 1:29 am

Although they are normally a little more than the other two, you won't regret it. Scooterwest.com carries them.

Hwarang · Post by **Hwarang** » Tue May 01, 2012 1:40 am

tenshi wrote:Although they are normally a little more than the other two, you won't regret it. Scooterwest.com carries them.

Tomorrow I have the day off to move into my new pad. If the movers wrap up in time, I'm going to explore Chicago a little bit (and probably end up at Scooterworks).

tenshi · Post by **tenshi** » Tue May 01, 2012 1:46 am

Ask them when they'll be getting the NCY transmission kit back in stock for me. I need it for my blackjack.

Hwarang · Post by **Hwarang** » Tue May 01, 2012 1:51 am

tenshi wrote:Ask them when they'll be getting the NCY transmission kit back in stock for me. I need it for my blackjack.

Ok, it's on the list!

CAPE COD PSYCHO · Post by **CAPE COD PSYCHO** » Tue May 01, 2012 5:18 pm

I just got my Psycho 125 back this morning. I had the dealer do the first service and install ncy super transmission, 10g Dr. Pulley sliders, kevlar belt, jet the carb (100), and take the restrictor out of the airbox. It sounds awesome! He said it takes off really well.

Unfortunately for me, it's pouring rain here today and I can't take it for a ride! Murphy's Law. I'm dying to go for a ride. I'll let you know how it all goes when I finally get to ride it!

k1dude · Post by **k1dude** » Tue May 01, 2012 5:48 pm

CAPE COD PSYCHO wrote:I just got my Psycho 125 back this morning. I had the dealer do the first service and install ncy super transmission, 10g Dr. Pulley sliders, kevlar belt, jet the carb (100), and take the restrictor out of the airbox. It sounds awesome! He said it takes off really well.

Unfortunately for me, it's pouring rain here today and I can't take it for a ride! Murphy's Law. I'm dying to go for a ride. I'll let you know how it all goes when I finally get to ride it!

Let us know if you loose top end. Supposedly with 10g sliders, you should loose some top end. I'm curious how much.

tenshi · Post by **tenshi** » Tue May 01, 2012 10:43 pm

Just saw that NCY Super Tranny is back in stock at Scooterworks.com. Can't wait until payday.

Hwarang · Post by **Hwarang** » Thu May 03, 2012 1:24 pm

tenshi - didn't get to scooterworks yet. no time on a weekday (they're not open very late).

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