Do these 2 stroke motors make more power when it's hot out? Tonight I was riding in 65 degree temperatures and my motor had trouble getting much above 215 degrees. When it's in the upper 80s it seems to make a little more power and I've see it get up to 290 degrees. So far I think the fastest speed I've seen was on the hotest day.
Do China Girls like warn weather?
- Thread starter biknut
- Start date
With most engines, the opposite is true. They like cold weather. Cold air is denser that hot air and this allows for a denser intake charge to fill the combustion chamber. More fill = more power.
These China Girls are finicky sometimes so I suppose that anything is possible with them. Perhaps yours is cold blooded and likes the extra heat?
These China Girls are finicky sometimes so I suppose that anything is possible with them. Perhaps yours is cold blooded and likes the extra heat?
I don't know about China girls but Vietnamese girls seem to like warm and humid!
Sorry, personal experience excepted, chances are they like warmer and (in fact) humid conditions. More dense air = better combustion.
Sorry, personal experience excepted, chances are they like warmer and (in fact) humid conditions. More dense air = better combustion.
i've ridden mine in 100+ weather and it runs fine, and in Southern California, the coldest i've ridden is probably 60 degrees.
mine seems to run better when it's colder, like 65-70.
i know there's plenty of guys out there that ride in the snow and freezing temps, along with the guys in AZ who ride in extreme heat, so they'll run at pretty much any temp.
mine seems to run better when it's colder, like 65-70.
i know there's plenty of guys out there that ride in the snow and freezing temps, along with the guys in AZ who ride in extreme heat, so they'll run at pretty much any temp.
Within "normal" temperature ranges (roughly -20 to 100+°F) the only difference as far as the engine is concerned (the rider may be disgruntled lol) is the fuel air mix as the colder it is outside, the denser the air is as others have mentioned (dense air = more of it per volume = leans fuel/air mix).
However, as it can be somewhat of a drastic difference in density with the average, noticeable performance change (with the HTs anyway) in an approximate 30° range (if tuned for 80° you'll note a pronounced difference at around 50° etc.) - as most HTs are running a touch rich - not only do you get a performance increase as you can get "more" air crammed into the combustion chamber per compression stroke (kinda like a weak supercharger), you'll get the added performance of a closer to correct fuel/air mix (NT & Speed carbs).
Needle clip position alone isn't really sensitive enough to compensate for this, nor is the difference in density usually enough to damage anything due to a lean condition (provided you're not running lean to begin with) but if you're noticing a pronounced improvement in performance on hot days & running poorly on cold (test w/just a hair of choke for improvement) - you may be running too lean in general & should prolly check your plug's coloration & condition.
I ride year-round in conditions ranging from -40 to 110°F and although there's a somewhat drastic change in performance in that range, I don't bother re-tuning, needle clip position has a pronounced enough effect that it'll never be quite "perfect" anyway I figure - fortunately & purely coincidentally my winter beater loves the cold (that carby runnin' rich) and my summer cruiser the heat (& that 'un runnin' lean) anyway
Ofc as the "quality" control of these motors varies as greatly as the elevations they're used at (higher the elevation = lesser the air density), as I'm at sea level in the frozen northlands & we all favor different oil/fuel ratios (less oil = more fuel = richer air/fuel mix) my observations may vary greatly from yours heh
However, as it can be somewhat of a drastic difference in density with the average, noticeable performance change (with the HTs anyway) in an approximate 30° range (if tuned for 80° you'll note a pronounced difference at around 50° etc.) - as most HTs are running a touch rich - not only do you get a performance increase as you can get "more" air crammed into the combustion chamber per compression stroke (kinda like a weak supercharger), you'll get the added performance of a closer to correct fuel/air mix (NT & Speed carbs).
Needle clip position alone isn't really sensitive enough to compensate for this, nor is the difference in density usually enough to damage anything due to a lean condition (provided you're not running lean to begin with) but if you're noticing a pronounced improvement in performance on hot days & running poorly on cold (test w/just a hair of choke for improvement) - you may be running too lean in general & should prolly check your plug's coloration & condition.
I ride year-round in conditions ranging from -40 to 110°F and although there's a somewhat drastic change in performance in that range, I don't bother re-tuning, needle clip position has a pronounced enough effect that it'll never be quite "perfect" anyway I figure - fortunately & purely coincidentally my winter beater loves the cold (that carby runnin' rich) and my summer cruiser the heat (& that 'un runnin' lean) anyway
Ofc as the "quality" control of these motors varies as greatly as the elevations they're used at (higher the elevation = lesser the air density), as I'm at sea level in the frozen northlands & we all favor different oil/fuel ratios (less oil = more fuel = richer air/fuel mix) my observations may vary greatly from yours heh
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Now see? I was going to say something like that but decided to stay professional so here goes:
Barley Awake makes some good points and one that I don't think of much anymore because I've lived at such a high altitude for so long that I just don't consider it. Altitude has a profound effect on any internal combustion engine. We who live in the 5 to 6000' range, and some even higher, take for granted that our engines perform a certain way. When a guy posts that he normally cruises at 33 to 35mph with a 41T sprocket some of us high altitude guys scoff at that. I know I do. Then I stop and look at his location and it hits me; Hey, he's just at sea level. No wonder his engine can make that kind of power. I'd love to take my best running bike down to the beach somewhere and see what it can do. I might have to adjust some but its a good bet that it would be an even better running bike down low, than up here at 6000' where the air is thin.
Now for temperature. I can't honestly say that I've noticed a lot of difference. This past summer we never saw 100 degrees in Denver but had lots of 90s and high 90s. My bikes seemed to run the same as they do when it's in the 20s and 30s. I don't do as well at those temps but the little Chinese thing between my legs (no pun) seems to run the same.
Whatever. Just tossing in my input.
Tom
