px extra cooling

[ducksta]

results in barrall temp without fan fitted 34 degrees barrall temp with fan fitted and running over same distance 32 degrees so not much in it.
but i tried

[sean brady scooters]

very interesting though and it did after all cool the barrel by a couple of degrees ,but maybe the cylinder head ran hotter instead as the air flow from your little electric fan just blasted down over the barrel and possibly diverted the cooling air in that direction .
temp tests on cylinder head are more important i think .
how did you measure the temp ?

[ducksta]

sorry sean i tested the head in the same spot streight down the spark plug gap in the cowling, i used a digital infa red thermometer

[Morgan]

looks positive. I'd check how it does on long runs and short runs, basically the more tests the better. I wonder what it's like through town as opposed to open road. maybe get a proper cht gauge and get it more accurate ?? Might be onto a winner there mate, get yur patent sorted

[ducksta]

i ran it around the york bypass then through town stopped took the reading on tick over, conected the fan then retraced my steps took the 2nd reading when back home

[Morgan]

Ahhhh...a flaw in your test. The first reading was at the end of a run through town whereas your second reading was at the end of a by-pass run. different runs with different cooling characteristics. Keep up with it though.

[ducksta]

but the engine had run twice as long but still cooled so is that a better result

[Morgan]

Not necessarily. Run 1 could have been up hill or into a head wind, therefore the return would be down hill with a tail wind. Try doing the same run but reverse the fan off/on and see if that produces the same results. Time can be an issue, but the strain on the engine is more important to produce heat. Another quick test would be to run scoot with fan off, leave on tickover for say 5 min then check temp, then repeat with fan on. It may be that the fan improves cooling in slow moving traffic but detracts from cooling on motorway running or vice-versa ???

I think a cht would be a big improvement in testing as when driving,you could monitor the temp when the fan is switched on and clearly see if the temp raises, falls or remains as is

[ducksta]

could put the fan at a angle to go with the flow of the flywheel? or just take it off lol

[bryansmudge]

Why not turn the fan round so that its sucking the hot air out of the cowl aiding the forced supply air from the flywheel while your at it. You may have to put some sort of baffle in place to redirect the ehaust air from your fan if its hot enough, to prevent the air space around the carb from heating up too much causing the fuel in the carb and fuel supply line from gasing off.