Hesitation at mid-high revs: jets?
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Addicted
1981 P200E / 1979 P200E / 1974 Rally 200
Joined: 30 Jul 2009
Posts: 561
Location: San Francisco, CA
Sun Apr 04, 2021 4:05 pm quote
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.
Moderator
VNB VSC VBC VSX
Joined: 28 May 2008
Posts: 4796
Location: Hustletown, TX
Sun Apr 04, 2021 5:15 pm quote
Can you pull the stack and let us know what your running?
Addicted
1981 P200E / 1979 P200E / 1974 Rally 200
Joined: 30 Jul 2009
Posts: 561
Location: San Francisco, CA
Sun Apr 04, 2021 6:23 pm quote
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).
Ossessionato
Joined: 22 Oct 2011
Posts: 4399
Location: Tega Cay, SC
Mon Apr 05, 2021 3:56 am quote
On a stock P200, the 118 jet is for premix, the 116 is for when using the autolube system.
Addicted
1981 P200E / 1979 P200E / 1974 Rally 200
Joined: 30 Jul 2009
Posts: 561
Location: San Francisco, CA
Wed Apr 07, 2021 8:02 pm quote
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?

IMG_0780.JPG

Ossessionato
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 2200
Location: california
Wed Apr 07, 2021 8:06 pm quote
Yup - little jet on the end. It plugs in and out - and magnifying readers are your friend...
Addicted
1981 P200E / 1979 P200E / 1974 Rally 200
Joined: 30 Jul 2009
Posts: 561
Location: San Francisco, CA
Wed Apr 07, 2021 9:05 pm quote
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.
Ossessionato
VSX, Stella 177, VNX1T, V9B1T
Joined: 20 Jul 2018
Posts: 2906
Location: Staten Island, NY
Thu Apr 08, 2021 12:55 am quote
Cdi?
Molto Verboso
2007 Stella 225
Joined: 02 Nov 2019
Posts: 1571
Location: Rochester, Minnesota
Thu Apr 08, 2021 4:27 am quote
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.
Ossessionato
VSX, Stella 177, VNX1T, V9B1T
Joined: 20 Jul 2018
Posts: 2906
Location: Staten Island, NY
Thu Apr 08, 2021 5:47 am quote
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.

emulsiontube.jpg

Addicted
1981 P200E / 1979 P200E / 1974 Rally 200
Joined: 30 Jul 2009
Posts: 561
Location: San Francisco, CA
Thu Apr 08, 2021 12:50 pm 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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