Author Topic: 750: CR style return line oil cooler  (Read 1515 times)

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Offline Garage_guy_chris

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750: CR style return line oil cooler
« on: July 07, 2016, 09:43:19 PM »
Ok so with the hot summer temps and humidity and city traffic my overheating problem is back and causing alot of "stop to cool the bike off" Since this weather is here i have been thinking about oil coolers again.  Now i have seen the sandwich plate coolers that go under the filter housing and I even have a sandwich plate fresh from the swap meets. Now the problem comes in because i have the hindle 4-2-1 exhaust and there isnt enough clearance to run a sandwich plate.

What I have seen while screwing around on the net is the CR750 style coolers that go inline with what looks like the scavenging / return side of the engine to oil tank,  oil line. generally the line comes off the engine goes to a cooler mounted up front and then goes back to the oil tank. 

I do have a couple questions about such a setup:
-It is the outer scavenging line NOT the supply line that these systems use.
-Does a system like this work on a street bike?
-Will a system like this overcool in milder weather?
-Is a stock oil pump up to the task of scavenging with the extra hose and cooler?

« Last Edit: July 08, 2016, 06:07:32 AM by Garage_guy_chris »
1971 Cb450 Cafe  (on the road)
1974 Cb750 Restomod (on the road)

Offline City Boy

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Re: 750: CR style return line oil cooler
« Reply #1 on: July 08, 2016, 07:54:20 AM »
Hi.Yes,you would route the oil return line to the cooler and then back to the tank.Yes,it will work fine on a street bike and the oil pump is up to the task.You may find overcooling in mild temps and at that point you will need to cover all or a portion of the cooler as required. Good luck.
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Offline Old Scrambler

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Re: 750: CR style return line oil cooler
« Reply #2 on: July 08, 2016, 11:46:37 AM »
+1 with City Boy.............where are your lights for the street?
Dennis in Wisconsin
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Offline turboguzzi

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Re: 750: CR style return line oil cooler
« Reply #3 on: July 08, 2016, 11:58:45 AM »
there is a reason why coolers are put in a pressure line. the scavenge pumps sucks a mixture of air and oil (it's a dry sump remember?) so the cooling will be less effective. not saying it will not cool at all, but not near to what it will do with a proper setup.

Offline Garage_guy_chris

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Re: 750: CR style return line oil cooler
« Reply #4 on: July 08, 2016, 09:55:51 PM »
+1 with City Boy.............where are your lights for the street?

thats not my bike, i just saw that picture showing a return line cooler.

It sounds like this may be a viable solution. Im gonna try to figure out a cooler core and the plumbing for it all and see what happens. 
1971 Cb450 Cafe  (on the road)
1974 Cb750 Restomod (on the road)