I have had outstanding results from the Lenale fan. If you want low cost effective oil cooler fans try Big Sky had their fans on 3 bikes with out a failure. They big sky fans are simple and easy to install
BIG SKY FAN
Don't kid your self to much on cooling the oil. HD engines do not flow enough oil to the heads to do much cooling once fully warmed up. However cooling the oil a bit can't hurt on a hot day.
This will give you an idea of the effect a lenale fan can have on head temps.
Lenale fan temps
No Harley was hurt in this test. Photos of temp displayed

Out side air was about 70 degrees
103 with lowers open
SYN 20/50 oil
Temp management off
No natural air flow
Started bike allowed to idle
At 261 turned on Fan
40 seconds dropped to 255
90seconds 239
120 seconds 225
at this point the drop slowed a bit
3 minutes 219
5 minutes holding 219 @ same 1000 rpms
7 minutes raised to 221
10 minutes 221 1000 rpms holding
Fan off
10 seconds 230
1 minute 248 climbing steady
1 minute 30 262
2 minutes 266
3 minutes 277
3minutes 20 280
4 minutes 293
FAN on drops of 1 degree per second or so
2 minutes 260
3 minutes 248
4 minutes slowed to 237
FAN off allowed to come to 331
Fan on
Fast drop
1 minute 289
came back down to 228
So there it is for now I will do more as I have time.
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