Hello

I have had cam seizures twice. Hopefully to stop it happening again I have fitted a pressure gauge on the output of the oil pump. So at least I get an early warning.

But, the pressure output has surprised me. The gauge is calibrated 0-10 bar. O-5 would have been better but I couldn’t get one. When the engine is cold the pressure varies between 1 bar (14.5 psi) and 4 bar (58 psi) at 3,000 revs. But when the engine warms up the pressure drops to 0 bar at tick over and 2 bar (29psi) at 3,000 revs.

There is a phenomenal drop in oil pressure as the engine heats up. I have heard oil pressure drops off as temperature increases specifically in motor cycle oil pumps but the I didn’t expect this degree of difference. I don’t know of anyone who has fitted a pressure gauge to a TR1 so have nothing to compare it to.

Is this normal?

Note: Photo attached of adaptor and pressure gauge fitted.

Photo adaptor

Photo mini Oil pressure gaude fitted.

You should drill a bigger bore into the screw that holds the 2 oil lines that go to the cylinder heads, and replace the oil pump with the bigger one from the xv1100. That should do the trick. What kind of oil are you using?

Bye,
Georg

Hello Georg

Thanks for the response.

The oil I am using is Castrol GTX 10w40 part synthentic.

I have drilled out the oil way through the bolt.

I do have an XV1100 oil pump I can fit. But I wanted to understand if this low oil pressure is normal with a standard TR1 oil pump when the engine heats up?

Regards
Kevin

Hello Kevin,
i´ve mounted an Pressure Instrument (as it is used for cars) since some years, it´s not exact but it can give me a warning, in case something is wrong. I use a pump of the newest type, is from the bt1100, i think Yamaha had 3 different types, XV1000,  early  XV1100 and new XV/Bt1100.

I mounted an oil-pipe from the crankcase underneath the starter, just before the Oil passes the Filter.
Then it´s "converted" to an electric Signal and a wire goes to the Instrument.

When the Oil -the Engine- is cold, it shows me very high pressure, even at 1000RPM, at the end of the scale with 5 bar. When the engine is hot, the pressure shown is at max. 1 bar at 1000, but at 3000 it rises to 3 bar, at 5000 i think the bypass (4-5 bar) opens, the pointer is kind of flouncing (maybe not the right expression?).
So-hot oil =low pressure is normal. The hole drilled into the screw you showed should not be wider then 2,5 mm, otherwise the pressure goes low.
As i wrote, my instrument is not exakt, and it depends on the position where you are measuring,
Regards Ali

I would assume that what you see is really not so much low pump performance, but rather low pressure drop across the flow path. That would tell me that your flow is good (definitely not lower than with a cold engine) and that you should get enough oil to the locations where you need it - you do have a newer/bigger pump, so that the flow concern has been eliminated. If now something plugs up you will see high pressure - that would then be a problem!

Holger

Well, I guess I could have read your post completely before putting my 5 ct in...
Of course you have not put in the other pump yet => what do you know about the status of your original pump? Is it possible that it is severely leaking internally?

Holger

kdemery wrote:

The oil I am using is Castrol GTX 10w40 part synthentic.

I prefer 15W40 or 20W50, but only plain old mineralic. Or are you riding in siberia? ;-)


Quote:

I do have an XV1100 oil pump I can fit.

Then fit it! The original pump has also a quite small intake filter, that is often clogged with dirt.


Quote:

But I wanted to understand if this low oil pressure is normal with a standard TR1 oil pump when the engine heats up?

With the thin semisynthetic oil and the original (eventually worn out a little bit) oil pump this can be possible, i believe.

Bye,
Georg

Hello Geog, Ali & Holger

Thanks for your support. I should note the the bike is running very well. If I hadn't fitted the pressure gauge I would have had no concerns.

My TR1 oil  pump is the original but the bike only has 12,000 miles on it (18,000 kms). So very low milage. I think the oil pump is OK.

The XV1100 pump I have in an unknown. I need to check it before I install in the TR1. But Georg, I take your point and should install it but I will get it checked first.

So, what I gather is the following:

1. Lower oil pressure as the engine warms up is normal.
2. When the engine has warmed up low pressure is good as it indicates there are no blockages in the oilways.
3. I should fit a better oil pump. I will do that when I have checked mine out.
4. I don't live in Siberia so I should be using 20W40 oil. I will change the oil and see what difference that has on the pressure.

Thank you all for your help.

Regards
Kevin

Hello Kevin,

just a little remark,
at the bolt to the heads the pressure is much less than just behind the pump. Measuring at the bolt means  Oil has been pressed (hopefully)  trough  the other channel to the crank, Rods, and is spilled to the Piston-Bolt and so on and that of course lower down the pressure at the upper point.
The main reason for pressure drop at a hot engine is that the Material of the parts to be oiled is widening a lot, all the clearences and gaps are much wider then. So there should be some pressure to avoid friction, and it lowers down the more up it has to be pressed. Very low Pressure also can  indicate clearences are out of the specified range, esp. lower rod-bearings. In my opinion a pressure of 1 or more bar at the head-pipes with a hot engine is good.
I use Castrol 20-40 or 20-50 Oil mineralic stuff for bikes , its not the cheapest, but when i make a change after 6000-8000KM it still looks and smells like Oil ,
Regards Ali

Hello Ali

You have made a very good point here that I missed. Because I am measuring the oil pressure at the bolt I am measuring the oil pressure to the heads not the output of the oil pump.

I feel a lot more comfortable about the lower pressure now.

Just for information. I wanted to change my oil to a higher viscosity to see if it improved pressure at higher temperatures. I wanted to use a 20w40 but could not find any so I changed the oil from 10w40 to 15w40. It has made no noticeable change to the indicated oil pressure.

Thank you for your help. I hope I will see you at the rally.

Regards
kevin

kdemery wrote:

Photo mini Oil pressure gaude fitted.

I want to get this awesome mini gauge.
please tell the details of this mini oil pressure gauge.

Regards
MORI

Hello Mori

I purchased the pressure gauge from www.miniaturepressuregauge.com.

It is described as a '23mm Pressure Gauge 0-10 bar 1/8 Npt'. Total cost to be including taxes and postage was £21.60.

You will need to make up a new bolt to replace the existing banjo bolt.

Regards
Kevin

Hello Kevin

Thank you for letting me know.
I think your place is also good.
I'm going to think about new configuration of the mounting location.

Thank you

Mori