Author Topic: Oil flow problems  (Read 851 times)

Propellor

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Re: Oil flow problems
« Reply #15 on: June 29, 2015, 11:35:26 AM »
Thanks for that info,  I dont think raising the oil tank would solve the problem, XL and XR's have the oil in the frame so should have a greater head of pressure to start with.
I meant the delivery pipe to the head, RS 600 flat trackers all ran a big bore feed to the head
I think the problem lies at the pump, it needs to be larger running at a lower speed, spinning a standard pump faster would lead to worse cavitation problems I think

You're welcome.

Good point you make re oil in frame versions. But if there is cavitation it will almost certainly be a problem on the suction side of the pump. You'd need to find a way increasing the effective head felt at the suction port to the pump. Or lower the oil temperature. Or both!

I don't know enough to say whether rpm of the pump is the factor. But if it keeps the localised velocity of the oil low in the suction line, then I guess yes, that would move in the right direction to avoid cavitation. As far as I know anyway.

I'm not entirely sure how you'd test for proof of cavitation. Severe cases show eventually as little pockets of erosion into the metal, local to where the cavitation has occurred.

High running temperature and off road machines kind of go together. The power demand can be high, but the speed of the vehicle not that high. Maybe!?
BEIGE is all the rage

guest1230

  • Guest
Re: Oil flow problems
« Reply #16 on: July 04, 2015, 07:10:11 PM »
This may sound stupid but did you make sure the little orifice and o  ring between the pump and clutch cover stayed in place when rebuilding.  I had to lean my bike well over on side stand to get mine to stay in situ.  Plus the o ring can get squashed if you use non standard gasket as I did once. 

Nell

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Re: Oil flow problems
« Reply #17 on: July 05, 2015, 11:27:25 AM »
Coming back to my comments of 4th June on this thread when I suggested the oil tank internal screen / mesh filter may be restricted or blocked giving an oil flow problem to the pump. You said it is was 6000 miles since rebuilding the oil system which could be time enough to build up fine debris in the wire mesh to cause the problem. I changed the pump, "O" rings, oil hoses (thought it may be the internal wall of the inlet hose collapsing) without success. Priming the pump produced enough oil flow to the filter outlet to the cylinder head then nothing thereafter but bubbles. After cleaning the mostly blocked tank mesh and reassembling every thing there was immediate oil pressure to the head and no trouble thereafter.
A lot of work perhaps but if up to now all else has failed!!!

JOOLZ

  • Posts: 910
Re: Oil flow problems
« Reply #18 on: August 08, 2015, 09:26:57 AM »
I have had no more oil flow problems since I replaced the banjo's for 2, 8mm x 1.25 spigot and some big bore hose.

guest564

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Re: Oil flow problems
« Reply #19 on: August 09, 2015, 08:20:52 PM »
I wonder if the pipe was breaking down. I ran my XBR to 8500 and never had an issue, that was running Silkolene semi-synthetic bike oil.

JOOLZ

  • Posts: 910
Re: Oil flow problems
« Reply #20 on: August 10, 2015, 09:28:09 AM »
I checked to old pipe and its in perfect condition, so I dont think that was the problem, anyway Im pleased that I have no more problems there with the new setup

johnr

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Re: Oil flow problems
« Reply #21 on: October 19, 2015, 09:59:06 PM »
not knowing the engine but having had a similar problem on a different bike in the past, is there a chance that a restriction in the oil flow that should be there somewhere is missing? i had a kawasaki that had an oil flow problem to the top end, it was a real head scratcher, and turned out to have been the emission of a small jet that restricted oil flow in one oilway which when in place created a higher pressure behind it, oil still came through the jet, but the backpressure it created also forced the oil that was restricted by the jet to travel up another oilway in the engine. hope this makes sense!