Thread: FZR/FZS/SHO Cooling system
05-27-2009, 07:52 AM #1
FZR/FZS/SHO Cooling system
I was looking at the FZR/FZS/SHO cooling route of the engine. From the first glance it shows that the exhaust gets all the cool water before the poor engine. The cylinder head where all the power lies is the last to be cooled down.
The question is... if the in-coming water from the pump gets routed to the head first (get rid of the thermostat) then down to the block then out through the exhaust achive a much cooler running engine = more power if not the same?
I know engine temp have been discussed a lot and everyone has an opinion about whats the best engine temp, I am not talking about riding in ICE COLD water! In addtition to that please correct me if I am wrong but wouldnt power decrease as the engine temp increase?at least thats what i know in cars.
I bet some workshop is looking into this right now and will have a new cooling route to sell soon.
my 2 dirahms
05-27-2009, 10:36 AM #2
05-27-2009, 02:51 PM #3
05-27-2009, 04:18 PM #4
05-28-2009, 12:50 AM #5
05-28-2009, 12:53 AM #6
05-28-2009, 01:08 AM #7
This is not my area but here is what I think
No doubt the SHO cooling system is weak,
As soon as we put 40 hp in it over heats,
More hp more cooling lines are required, the whole engine and intercooler are fed by 1 small line, cant remember the size of the hole it goes through but its something like 10 -12 mm
Engines need temp to make power, the bores dont get round untill the heat builds up, most engines I have looked at with relation to this on the engine dyno make max power between 70-80 c (160-175)
(Just personal experiance here)
Engines also need even cooling, the best systems are closed loop where the temp is more controlable and even.
If your not closed loop then the best way to work it is to feed it through the exhaust manifold first to heat it up.
Problem with the Yamaha ,there is just not enough water flow to do the job once you start making more power.
05-28-2009, 03:15 AM #8
Pete, would you think if we increase the exit water instead of increasing the incoming water would cool the engine. As I see in the illustration all the water coming from the exhaust and the engine block gets cramped in the head then it has only one exit which is controlled by a thermostat. Taking out the thermostat and drilling one more exit hole for example 10mm in the front of the head (which really dangerous u can ruin the head) would allow more water to exit and in return enter also.
I am interested in this cuz our climate in the middle east is very hot now temps are around +40C. and we need to keep our engines running cool.
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