Cooling system mods.

Madman

Anyone modded cooling flow?
We are making an attempt at installing the 60mm impeller
from the newer motor into the old single phase side cover.

Its worth 15% increase in flow.
Will try and take some photo's of the conversion with parts used.

My 907 motor is not happy in the city streets.
Open roads is fine.
If i have time and access, i will dyno before and after to
see hp loss with the added drag.

Mr.R

Hi,
I haven't experimented with the flow but...
My '92 based 'Mildly tuned' 851/916cc motor 116 rwbhp@9,500 rpm doesn't really have a problem with over heating apart from when stuck in slow moving traffic* on a hot day and I don't run a fan,(removing the fan helps with the cooling as long as you can keep the bike moving)
I've got a genuine 888 Corse rad' (extra 3 rows at the bottom) to fit when I install my 984cc motor, which I hope to hit close to the 130 rwbhp mark at under 10,000 rpm.

*Not really what these bikes were intended for but...
If I get caught in a snarl up I just keep the bike moving while keeping an eye on the temp' gauge.
If the temp' gets too high, I just pull over and have a smoke while the motor cools down or turn the motor off when stuck at a standstill.
(Having a Hawker Odyssey battery helps here!)

Rather than play around with larger impellers, have you tried 'Water Wetter' or similar?
This stuff is ment to lower the temp' by at least 10%, how much extra heat can your 907 be kicking out?
I'm assuming that you're running a 95mm bore Hi Comp' 851 here??

Steve R

Madman

Steve

This is a 92 setup also.
Yes 95HC, stock stroke.
The motor loves to be run hard. The harder you run it
the cooler it runs. It just cannot take the city stop and go
in the summer.
Gearing has some input on running temps. If i go taller it
helps pull the heat back out of it faster. I run 15/36. Most run in the 40-42 area with a 15. I found it to be a coolant flow issue at the lower rpms.
Tried the usual quick stuff (wetter,man fan sw, higher press ect)
Ducati's answer was to increase the flow and pressure.

Bill

loony888

i put a custom rad on my 888, it's 7mm thicker, has larger cores and turbolators that move the coolant from the back to the front to the back and so on, the fan is gone and with engine ice i have had no overheating issues at all. the temp gets up in traffic but not to the point it boils and before, with the std rad and fan it ran hot too and the fan never came on soon enough!

paul.

Madman

loony888 wrotewith the std rad and fan it ran hot too and the fan never came on soon enough! paul.

Agree 100%!!! Its a problem with the 92 and newer coolant system.
The sensor at the midway point in the crossflow rad was just stupid
in oem form. (not enough coolant flow)
With a change in flow i expect to not need a fan and not have the
wide coolant temp swings. This shoud also make the ecu input (fueling)
more consistent. Sensor is on the rightside of front head!

Time will tell
Bill