Does cooler weather really enhance engine performance?

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Sep 26, 2015 | 01:47 PM

#11

ChickinOnaChain

Big Kahuna HDF Member

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From: .....

I always thought cooler weather just means cooler engine, which means happier engine.

Sep 26, 2015 | 02:31 PM

#12

Ink83

Road Warrior

Joined: Oct 2013

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From: Australia

Yep it's defintely true, on an injected engine the cool more dense air will allow the ecm to add more fuel

I live where temps easly get up to 100 plus, so when it gets cooler, it's really noticeable how much harder the bike pulls

Sep 26, 2015 | 02:37 PM

#13

Tired

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From: SWMO

I read awhile back that scientists are just a couple years away from growing new eyes. So, spank you plank at will.

Sep 26, 2015 | 05:41 PM

#14

electricstart

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Man I could use new eyes .My Harley motors seem to like the cooler less humid temps .

Sep 26, 2015 | 09:20 PM

#15

ILMFBL

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From: x

Hold on, my brale printer just quit.

Sep 26, 2015 | 09:59 PM

#16

Hey Man

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From: West Central FL

In my Shovelhead it sure does. Cold air enhances combustion.

Sep 26, 2015 | 10:01 PM

#17

lh4x4

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From: Illinois

I winter ride every year. Last winter from Nov. 1 to Mar. 31 I rode 9,740 miles.

The Softail Custom, Buell and a Freewheeler are my primary winter rides.

Soft 02's statement that old guys put their bikes away in the winter was a proven fact is pure myth. Most of the winter riders that I come across each winter are older. Maybe not as old as me(I'm 75) but certainly not the under 30 kids.

Back to the OP's question. As some have posted the O2 content is much higher in the winter but other factors play as big a role. The engine is colder also. So when the spark fires the dense incoming charge the expanding gas puts more pressure on the piston. The engine in the cold wind will dissipate the heat quicker and ready for the next shot. This does not happen in liquid cooled engines as much. The engine runs at a constant temp unlike the air cooled engine and just does not benefit as much. The incoming air charge has a longer path in the intake and gets warmed more before it enters the combustion chamber. It is just a short shot for the TC engine.

Riding in 20 degree weather is like giving the bike a constant shot of NO.

A 96 will feel like a 110. It is impressive. It is not so noticeable over the 40 to 50 range.

If it gets under 30 in your area this winter and the roads are clear. Just do a few miles and a couple of launches. You will love the experience.

Last edited by lh4x4; Sep 26, 2015 at 10:06 PM.

Sep 26, 2015 | 11:03 PM

#18

splattttttt

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From: MASS_hole

lh4x4, tanks you for sharing.
I've only been riding air cooled efi motorcycles since last year. Proud to say that it all started with a sporty and now a big twin. Both, 2014 models.
Been riding since moving to the Boston are in 84. All imports; and all water cooled.
It was vague to me last winter, though I was certain that my mildly tuned fls ran smoother with out hesitation and a felt, broader power band.
In fact today, I hardly needed to shift into sixth during my daily commute whilst cruising at my usual avg of 75mph.

Really wish there was a way to keep that air charge cool even in the middle of summer. Man what a difference!