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@hjo avatar
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Molto Verboso
Scattered remnants of (two!) 1974 Rallys
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Molto Verboso
@hjo avatar
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Curious about this.

The bike runs fine, but just feels like it loses power in upper revs. And doesn't ever reach super high rev. Not terrible, but the power band should be in the mid-upper range.

Definitely feels like it has more power on the low end, and gets weaker when you open up.

It's a p200, with a replacement SI 24 carb, and whatever jetting came with it.
@birdsnest avatar
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VNB VSC VMA VSX - o9c vbc vmb
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@birdsnest avatar
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Can you pull the stack and let us know what your running?
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@hjo avatar
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Molto Verboso
Scattered remnants of (two!) 1974 Rallys
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Molto Verboso
@hjo avatar
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I'll check. It looks like:

-Idle Jet: 55/160

Main Jet Stack:
-Air Jet: 160
-Mixer Tube: BE3
-Main Jet: 116

But some of them appear to have a 118 main jet.

(this is from Scooterwest, where I bought it. I haven't looked yet).
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Veni, Vidi, Posti
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Veni, Vidi, Posti
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On a stock P200, the 118 jet is for premix, the 116 is for when using the autolube system.
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@hjo avatar
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Molto Verboso
Scattered remnants of (two!) 1974 Rallys
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Molto Verboso
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Oh no. Glimpsing mortality.

There are probably numbers on here, but I can't read them!

The little jet at the end. That would be the 116/118?
Forum member supplied image with no explanatory text
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Nedminder
62 VBB1T Round Tail W/ leaner sidecar
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Nedminder
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Yup - little jet on the end. It plugs in and out - and magnifying readers are your friend...
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@hjo avatar
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Molto Verboso
Scattered remnants of (two!) 1974 Rallys
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Molto Verboso
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Cleaning it helped!

It's 116. And the bigger one is BE3.

The small jet is interesting. It doesn't connect.

So the angled part at the bottom forms a seal, and the fuel flows in from the side, and out the bottom?

The bike runs ok, it just has the most power in the low-mid revs, then feels like it loses power. And it doesn't rev super high, even in third gear.

I've ridden tuned/kitted bikes, and all the power on those is in the high range.
@swiss1939 avatar
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Ossessionato
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
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@swiss1939 avatar
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
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Cdi?
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2007 Stella 225
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Ossessionato
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hjo wrote:
Cleaning it helped!

It's 116. And the bigger one is BE3.

The small jet is interesting. It doesn't connect.

So the angled part at the bottom forms a seal, and the fuel flows in from the side, and out the bottom?

The bike runs ok, it just has the most power in the low-mid revs, then feels like it loses power. And it doesn't rev super high, even in third gear.

I've ridden tuned/kitted bikes, and all the power on those is in the high range.
One of the jets I haven't looked in a few months has air coming in from the top and fuel coming in from the bottom. Those two mix for your ratio.
@swiss1939 avatar
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Ossessionato
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
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@swiss1939 avatar
P208, Stella VMC Stelvio 187, Stella 150, VNX1T, V9A1T, V9B1T, 02 Sportster XLH1208
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Air from the air corrector.. fuel from the bottom where the main jet comes in. They both mix in the atomizer as the fuel level starts high and drops down under throttle.
Forum member supplied image with no explanatory text
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@hjo avatar
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Molto Verboso
Scattered remnants of (two!) 1974 Rallys
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Molto Verboso
@hjo avatar
Scattered remnants of (two!) 1974 Rallys
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Posts: 1847
Location: San Francisco, CA
UTC quote
That diagram makes sense!

So the upper range RPMs are not the main jet, but the BE3 one?

The CDI. Do those decline over time? I've had one fail, and it seems like it either works perfectly, or not at all. And will just instantly stop. It happened on a ride, one minute it was fine, then just stopped providing spark.
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