Motor temperatures

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windweaver
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Re: Motor temps

#16

Post by windweaver »

they all sound logical to me WW
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Re: Motor temps

#17

Post by Pantony »

Panzerama; it think your correct in your cause of running hotter in the front, as I remember the cam profile is also different between front and rear to compensate for some of this energy irregularity. I have read Cottens post on his "physical" readings as well as yours and seguway to the bikes heat, Pantony will not under any circumstances be sticking his tongue or forehead on the 48FL anytime soon.
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Re: Motor temperatures

#18

Post by 58flh »

I think everyones theory makes sense to some degree,hence what Cotton said a variety of factors.I also think that when moving down the road the fuel mix. can be more dispersed towards the rear cyl.! Thats why alot run richer at the rear cyl. & leaner in the front cyl.--If you look at the plugs!--This I believe is just another factor in the good theorys already explained. And the front cyl. fires first,I would like to see temp. results in a singlefire set-up! Anyone running this?----RICHIE :?
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Re: Motor temperatures

#19

Post by kitabel »

The rear cylinder is continuously cooled by oil throw-off from the rods and wheels, the front isn't (even with the baffle).
The older engines have symmetrical cam timing.

because of the same thing that makes hot water pipes freeze before cold water pipes
Which is what?
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Re: Motor temperatures

#20

Post by 59Panman »

58flh wrote:I think everyones theory makes sense to some degree,hence what Cotton said a variety of factors.I also think that when moving down the road the fuel mix. can be more dispersed towards the rear cyl.! Thats why alot run richer at the rear cyl. & leaner in the front cyl.--If you look at the plugs!--This I believe is just another factor in the good theorys already explained. And the front cyl. fires first,I would like to see temp. results in a singlefire set-up! Anyone running this?----RICHIE :?
Richie,

I am trying to understand your statement that "the fuel mix can be more dispersed towards the rear cylinder" :?:
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Re: Motor temperatures

#21

Post by Cotten »

Folks,

These are all great questions that we are trying to answer from our armchairs.
Without data, we are conjuring.

Kitabel!

Unless you live where the hot water pipes freeze when the cold do not, I have no foundation to explain.
It is a real phenomenon, and I believe it applies to the front-hotter-than-rear heat signatures in our motors.

And ozwick86!

Richie may be referring to the bias created by a vertical throttledisc, as well as other theory.
Langsencamp & Linkert went horizontal for their DC models, and the rest is History.

....Cotten
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Re: Motor temperatures

#22

Post by 58flh »

Thank you!--Its what I was trying to get accross,---Now Along with that phenomena, with a naturaly apirated motor going forward!-The long intake of a pan -Do you think its possible that some of the atomized mixture will tend to flow towards the rear?---The reason I ask is My plugs were always richer in the back & leaner in the front!--When I pointed the pumpshooter a smidge towards the front cyl. instead of down the middle, My plugs now read the same!--I realize that the vacuum made is great on the intake downstroke. SO why does mine burn even now? & if you look at a fuel injected bike the plugs are identical.--Just something to think about. When going down the pike at 55-65 mph Do you think its possible that the mix would favour the rear? Or was my ADJ. of the shooter nozzle just at a better break-point for the 2 90 degree turns the mix has to make at the end of the intake to fill both cyl.?----Richie :?:
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Re: Motor temperatures

#23

Post by kitabel »

A hot surface will lose temperature faster than a cold surface through convection and radiation (in the same air temperature) because the heat transfer rate varies as the temperature differential.
This effect stops when the hot pipe cools to the same temperature as the cold pipe (which has itself been cooling at a slower rate).
The phenomenon is perceived, not actual.
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Re: Motor temperatures

#24

Post by 58flh »

KIT!---Hence similar to tubing on a hilbourne inj. for auto!--Longer the tube=faster the aceleration in velocity in it!---Richie
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Re: Motor temperatures

#25

Post by dontsink »

Great info for newbies - thank you!
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