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bike overheating

All oil filters are made with a safety so that "can't" happen, because flowing oil is more important than filtering oil.

However, on a really old filter it can happen from that safety getting stopped up too. Either way I'm glad your satisfied with how it's running now.

Any chance you could cut the other filter open and post some pics, so we can see what if anything was defective.

I dont think I threw it out yet, so I will cut it up and post some pics later
 
Bad oil filter...

Hmmmm....

It would be almost impossible for a oil filter to cause a bike to heat up quick or over heat.

Now if it was low on oil that could cause it, but the filter itself no.

Almost all filters these days have a bypass, but so does the oil pump (high pressure by-pass that is)!

This is the typical construction. That spring on the left; once the pressure to flow through the element exceeds the pressure needed to compress that spring it forces the filter LEFT and allows oil to flow directly from the outer body area into the core area and bypass the filter.
View attachment 43992
I'd imagine, this would quickly elevate the oil temperature if the filter was plugged and the bypass worked at a very low level as the pump would by struggling against the load. It can't be good.

If ever IN DOUBT; touch the filter and the pan area; they should be both be NEAR THE SAME TEMPERATURE! A COLD FILTER IS A BAD SIGN!!!!
 
Don't our engines also have a bypass right before the filter and after the oil pump in case a old filter were to get clogged up?
 
Don't our engines also have a bypass right before the filter and after the oil pump in case a old filter were to get clogged up?

It has a "relief valve" per page 5-43(Yamaha manual, 07-09), accessable from the oil pan. I'm not sure, but I believe it may be for too much oil pressure, not a bypass.

Seems really odd that the oil filter clogged up(unless original/never changed), overheated but kept running with no or little oil pressure AND NO MAJOR ENGINE DAMAGE..

And as posted above, the filter would have a bypass valve JUST for this potential problem, and that failed too...:confused:
 
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Yeah i looked all through the manual and service book and couldn't find exactly what it is supposed to be used for, but that makes sense.
 
^^ internally next to the pump inside the block is the OP relief valve. When the oil is cold and thick thus unable to push through the gallies, bearings, orifices, the internal over pressure relief may activate dumping some of the pumps oil right back into the pan. Same is true of high RPM.

From the o7 service manual it has this which shows what the pump must be capable of at a given RPM.
Oil pressure 240 kPa at 6,600 r/min
(2.4 kg/cm² at 6,600 r/min)
(2.4 bar at 6,600 r/min)
(34.1 psi at 6,600 r/min)

HERE is the info on the bypass filter recommendation by Yamaha and the engines internal over pressure relief.
Bypass valve opening pressure 80–120 kPa (11.6–17.4 psi). <internal to Filter.
Relief valve operating pressure 450.0–550.0 kPa (65.3–79.8 psi).
Of course it depends on the health of the engine, but rotary pumps (Trochoid) such as this tend to double the pressure when RPM is doubled so i potential that the engine is in dumping via the Relief valve over 10 - 12k but I'll never know until I put a pressure gauge on it!

Bottom line, A Yamaha APPROVED filter goes into by-pass if the pressure difference inside to outside of filter element is greater than 11.6–17.4 psi. What sucks about this is that during by-pass mode the debris trapped in the OUTER PLEATS of the filter have a direct path right back into the main galley of the engines oiling system. Only high end well designed filters prevent this.

EDIT: the Over Pressure relief is prevent stalling the oil pump and breaking it or the drive mechanism. Remember - fluids do not compress well and if it can't pump it, something has to give. better to dump it than break the chain or drive shaft.
 
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^^ internally next to the pump inside the block is the OP relief valve. When the oil is cold and thick thus unable to push through the gallies, bearings, orifices, the internal over pressure relief may activate dumping some of the pumps oil right back into the pan. Same is true of high RPM.

From the o7 service manual it has this which shows what the pump must be capable of at a given RPM.
Oil pressure 240 kPa at 6,600 r/min
(2.4 kg/cm² at 6,600 r/min)
(2.4 bar at 6,600 r/min)
(34.1 psi at 6,600 r/min)

HERE is the info on the bypass filter recommendation by Yamaha and the engines internal over pressure relief.
Bypass valve opening pressure 80–120 kPa (11.6–17.4 psi). <internal to Filter.
Relief valve operating pressure 450.0–550.0 kPa (65.3–79.8 psi).
Of course it depends on the health of the engine, but rotary pumps (Trochoid) such as this tend to double the pressure when RPM is doubled so i potential that the engine is in dumping via the Relief valve over 10 - 12k but I'll never know until I put a pressure gauge on it!

Bottom line, A Yamaha APPROVED filter goes into by-pass if the pressure difference inside to outside of filter element is greater than 11.6–17.4 psi. What sucks about this is that during by-pass mode the debris trapped in the OUTER PLEATS of the filter have a direct path right back into the main galley of the engines oiling system. Only high end well designed filters prevent this.

EDIT: the Over Pressure relief is prevent stalling the oil pump and breaking it or the drive mechanism. Remember - fluids do not compress well and if it can't pump it, something has to give. better to dump it than break the chain or drive shaft.

Yikes:
I looked up the spec on the filter i've been using:
By-Pass Valve Setting-PSI: 8 << (YAMAHA SPEC: 11.6–17.4 psi)

Which means as the filter saturates with particles, the lower by-pass mode likely means debris is being dumped back into the oil. OK time to use a different filter or change it more often. . . hint 51358
 
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