OP
UTC

Hooked
2005 Px150(Black) and 1983 P200
Joined: UTC
Posts: 143
Location: montreal
 
Hooked
2005 Px150(Black) and 1983 P200
Joined: UTC
Posts: 143
Location: montreal
UTC quote
So i have it running like a champ all summer,

a few days ago it developped a bog at WOT on uphills, when it used to never have that. I had that bog at the beggining of the summer, but since i drilled a hole in the air filter (heart shaped), that was forever gone...till now

Im talking sito plus and upjet. with the heart shape removed in the filter.

The temps have gotten on average 5-8 degrees C cooler than July....
And the bog feels like a rich bog (i can smell the gas)
My question is, how do cooler temperatures, given the same amount of fuel cause a rich bog? Would that not lean the mix out?

It only happens on uphills...under heavy load...the kind of speed where im at max WOT, on an uphill, neither accelaerating or decelerating.
@nigelthefish avatar
UTC

Ossessionato
ET2, PX150
Joined: UTC
Posts: 3410
Location: Denver CO
 
Ossessionato
@nigelthefish avatar
ET2, PX150
Joined: UTC
Posts: 3410
Location: Denver CO
UTC quote
So what jets are you running?
@aviator47 avatar
UTC

Moderator
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
 
Moderator
@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
UTC quote
Have you checked your spark plug?
@scooter_west avatar
UTC

Sponsor
Joined: UTC
Posts: 4200
Location: San Diego, Ca
 
Sponsor
@scooter_west avatar
Joined: UTC
Posts: 4200
Location: San Diego, Ca
UTC quote
Those Dellorto SI carbs don't seem very sensitive to temperature changes in my experience. I'd be surprised if 5-8 degrees made any difference at all. I know I've ridden to work at 60 degrees and home at 90 degrees without any real difference. I'd investigate other issues. We usually upjet from a 98 to a 102 with the Sito Plus on a PX150. I've not done the air filter mod before.

To answer your question about jetting; cold air is denser than hot air so cold air would add more air, leaning out the mixture.
OP
UTC

Hooked
2005 Px150(Black) and 1983 P200
Joined: UTC
Posts: 143
Location: montreal
 
Hooked
2005 Px150(Black) and 1983 P200
Joined: UTC
Posts: 143
Location: montreal
UTC quote
thanks for all the replies..
finnally checked the plug

est elle couleur chocolat.....after a nice wot run

so i guess im good...maybe when i run wot an extended period on uphills it runs out of fuel to the carb?
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