Pressure Gauge Adapted

[pete roper]

To be brutally honest I don't think most anti drain back valves are particularly effective in most oil filters.

 

All they are really is a sort of rubber diaphragm that sits inside the filter above the holes where the oil comes in, (The oil comes into the filter through the holes around the outside of the base-plate and then exits to the bearings through the orifice that screws onto the mount.). Certainly on my Patrol which has two oil filters, both with anti drain back valves, they seem to empty themselves if the time it takes for pressure to build up and the light to go out is any guide. It has always been thus.

 

One of the huge advantages the Guzzi motor has is that it has very short galleries. Once the pump is spinning, even at cranking speed, it takes next to no time for the galleries to fill. Even filling the filter doesn't take long. You can check this out by taking the plugs out and removing the ignition relay next time you do a filter change and put the filter on empty. Spin the motor on the starter and even at cranking speed it only takes a few seconds for the filter to prime. It's easier to see this on the older bikes that don't turn the idiot lights out while cranking but you can do it by pressing the button for a couple of seconds and releasing it, then repeating till the light doesn't come back on.

 

Obviously it's far better to prime the filter by filling it with oil but I wouldn't die in a ditch about it. Few car filters are primed before installation due to the fact that few of them sit facing down and most workshops just change the oil and filter and then fire the engine up, there is residual lubrication in there but it's best if you can get fresh oil flowing to the bearings immediately. Certainly starting an engine with a dry filter by planting your foot to the floor and 'firing 'er up' isn't a bright idea but priming at cranking speed, even with the plugs in, shouldn't do any major damage but I'd avoid it if I can.

 

Pete

[Ryland3210]

I believe there is a difference between pressure and flow. A thicker oil will build pressure quicker when cold but a thinner oil will flow to the bearings faster.

In my opinion, the pressure build is not because the oil is getting to the bearings quicker, but rather because it is resisting going to the bearings.

 

That depends on where the pressure is being measured. For example, if right at the pump outlet, your interpretation might be correct. On the other hand, if the pressure is monitored at the farthest point in the oil feed system from the pump, then it isn't. The location for my adapter is on the banjo fitting feeding the heads, which is somewhere in between.

 

Remember that the pump in question is a fixed displacement type, so the flow rate is the same, regardless of viscosity, unless the pump has significant leakage. However, if it does, the higher viscosity oil leaks less, and flow rate to the bearings will be slightly higher.

 

In the case where there is no significant pump leakage, even though the flow rates are the same and oil reaches the bearings at the same time, higher viscosity oil builds pressure faster because the pressure drop through the bearings is higher.

 

There is the pressure relief valve to consider. Until pressure reaches its cracking pressure, the full flow of the pump is delivered to the bearings. If the passages to the bearings were very small, then your point would be well taken, since the relief valve might bypass oil before it got to the bearings, and lower viscosity oil would have the advantage. However, I suspect, admittedly without having looked into the passage designs, is that they are designed to provide very little flow restriction.

[Ryland3210]

Is it possible to get the gauge in white to match the veglia of earlier v11 bikes?

 

No problem.

[dlaing]

No problem.

Are you selling kits?

EDIT I guess so. From an earlier post you posted your website http://www.motratech.com/Welcome.html

Have you made a setup for the V11S?

Or a discounted setup where we have to figure out where to mount it?

[Ryland3210]

Are you selling kits?

EDIT I guess so. From an earlier post you posted your website http://www.motratech.com/Welcome.html

Have you made a setup for the V11S?

Or a discounted setup where we have to figure out where to mount it?

 

Yes, I have been making up kits, but volume has been low, so I haven't been able to justify a modified mounting scheme. One customer has used an existing location on the instrument panel and one of the two screw locations on the adapter. It seems to work fine.

 

I believe the manifold the gauge mounts to is compact enough that it should be straightforward to make up a sheet metal plate for it to connect to using the two screw locations. The DIY sheet metal fabrication would be made to adapt to the forks, or the brackets for the clutch or brake lever. I guess my answer is that it only makes sense to offer complete kits as they are.

[Ryland3210]

To be brutally honest I don't think most anti drain back valves are particularly effective in most oil filters.

 

All they are really is a sort of rubber diaphragm that sits inside the filter above the holes where the oil comes in, (The oil comes into the filter through the holes around the outside of the base-plate and then exits to the bearings through the orifice that screws onto the mount.). Certainly on my Patrol which has two oil filters, both with anti drain back valves, they seem to empty themselves if the time it takes for pressure to build up and the light to go out is any guide. It has always been thus.

 

One of the huge advantages the Guzzi motor has is that it has very short galleries. Once the pump is spinning, even at cranking speed, it takes next to no time for the galleries to fill. Even filling the filter doesn't take long. You can check this out by taking the plugs out and removing the ignition relay next time you do a filter change and put the filter on empty. Spin the motor on the starter and even at cranking speed it only takes a few seconds for the filter to prime. It's easier to see this on the older bikes that don't turn the idiot lights out while cranking but you can do it by pressing the button for a couple of seconds and releasing it, then repeating till the light doesn't come back on.

 

Obviously it's far better to prime the filter by filling it with oil but I wouldn't die in a ditch about it. Few car filters are primed before installation due to the fact that few of them sit facing down and most workshops just change the oil and filter and then fire the engine up, there is residual lubrication in there but it's best if you can get fresh oil flowing to the bearings immediately. Certainly starting an engine with a dry filter by planting your foot to the floor and 'firing 'er up' isn't a bright idea but priming at cranking speed, even with the plugs in, shouldn't do any major damage but I'd avoid it if I can.

 

Pete

 

Good practical data. I'm still not sure whether it's better to start the engine and keep it at idle, or reduce the time to build pressure by going to 2,000 RPM, for example. In journal bearings, hydrodynamic oil film is easier to maintain at higher RPM's all other things being equal. So one way to look at it is that if there is residual oil in the bearing, perhaps metal to metal contact is better avoided by immediately going to a moderate RPM as soon as she starts.

[dlaing]

Good practical data. I'm still not sure whether it's better to start the engine and keep it at idle, or reduce the time to build pressure by going to 2,000 RPM, for example. In journal bearings, hydrodynamic oil film is easier to maintain at higher RPM's all other things being equal. So one way to look at it is that if there is residual oil in the bearing, perhaps metal to metal contact is better avoided by immediately going to a moderate RPM as soon as she starts.

I'd agree with that, but I think that above 2000RPM you get diminishing returns.

Without scientific backing, I would guess 1500-2000RPM is ideal.

1000-1200RPM may be too gentle...

What pressure readings do you get during a cold start at various RPMs? How does that reading relate to actual bearing oil pressure?

[Ryland3210]

I'd agree with that, but I think that above 2000RPM you get diminishing returns.

Without scientific backing, I would guess 1500-2000RPM is ideal.

1000-1200RPM may be too gentle...

What pressure readings do you get during a cold start at various RPMs? How does that reading relate to actual bearing oil pressure?

 

Hi Dave,

 

In an earlier post, I reported:

 

"One of the members and I have been discussing how fast oil pressure builds on cold starts with 15W40 oil. I thought I would share the results with everyone.

 

I left my beloved bike out in the cold last night, knowing it was going to dip below freezing. There was still frost on the grass and the air temperature was 34 F. There was condensation on the bike, so I knew it was good and cold.

 

While I was cranking to get it started, pressure started to build almost instantly. Within 3 seconds of relatively slow cranking, before the engine even sputtered, pressure was up to 20 psi and climbing fast. I estimate the engine was turned over 10 revolutions at most, by which time it reached 40, and still kept climbing. When it started, it jumped to 65. at 2000 RPM, it was at 80 psi, which appeared to be the relief valve's effective limit at this low an oil temperature. Normally it stays around 50-60 when fully warmed up, depending on ambient temperature.

 

Conditions are my '04 Cafe Sport with about 4000 miles, Purolator L10241 filter, 15W40 Shell Rotella oil."

 

This is an extreme condition, but it's all the data I have at the moment. Had the bike not started, it was heading for over 40 PSI at idle. My recollection is that it was around 65 psi at idle.

 

Since then, I have changed to 20 W50 oil. I'll see if I can start the bike at a more typical temperature and report back, but I want to wait until it's a decent riding day. I don't want to start it without giving it a good run, and it's snowing.

[Ryland3210]

Hi Dave,

 

In an earlier post, I reported:

 

"One of the members and I have been discussing how fast oil pressure builds on cold starts with 15W40 oil. I thought I would share the results with everyone.

 

I left my beloved bike out in the cold last night, knowing it was going to dip below freezing. There was still frost on the grass and the air temperature was 34 F. There was condensation on the bike, so I knew it was good and cold.

 

While I was cranking to get it started, pressure started to build almost instantly. Within 3 seconds of relatively slow cranking, before the engine even sputtered, pressure was up to 20 psi and climbing fast. I estimate the engine was turned over 10 revolutions at most, by which time it reached 40, and still kept climbing. When it started, it jumped to 65. at 2000 RPM, it was at 80 psi, which appeared to be the relief valve's effective limit at this low an oil temperature. Normally it stays around 50-60 when fully warmed up, depending on ambient temperature.

 

Conditions are my '04 Cafe Sport with about 4000 miles, Purolator L10241 filter, 15W40 Shell Rotella oil."

 

This is an extreme condition, but it's all the data I have at the moment. Had the bike not started, it was heading for over 40 PSI at idle. My recollection is that it was around 65 psi at idle.

 

Since then, I have changed to 20 W50 oil. I'll see if I can start the bike at a more typical temperature and report back, but I want to wait until it's a decent riding day. I don't want to start it without giving it a good run, and it's snowing.

 

Two reports:

 

1. I started the bike this morning after it was in the garage all night at about 60 degrees F. It idled at 60 psi with the 20W50 oil.

 

After warming it up, riding in 30 degree weather, pressure stayed at 65 psi when cruising. Interestingly, it was at 60 at idle, and also at WOT acceleration.

 

2. With Roper Plate installed, refilled with 4 quarts, pressure remained at 60 from 2000 to redline in first gear and also through second, both at WOT without "wheelies". This verifies that it cured the pump starvation I had experienced before installation of the Roper Plate. I cannot say what would happen if one executed a wheelie. I'm happy with the results from the Roper Plate. My recommendations are to avoid WOT in first gear if you do not have one of these valuable additions, and to refill with 4 quarts with filter change, and keep the oil level up there.

[pete roper]

1. I started the bike this morning after it was in the garage all night at about 60 degrees F. It idled at 60 psi with the 20W50 oil.

 

After warming it up, riding in 30 degree weather, pressure stayed at 65 psi when cruising. Interestingly, it was at 60 at idle, and also at WOT acceleration.

 

2. With Roper Plate installed, refilled with 4 quarts, pressure remained at 60 from 2000 to redline in first gear and also through second, both at WOT without "wheelies". This verifies that it cured the pump starvation I had experienced before installation of the Roper Plate. I cannot say what would happen if one executed a wheelie. I'm happy with the results from the Roper Plate. My recommendations are to avoid WOT in first gear if you do not have one of these valuable additions, and to refill with 4 quarts with filter change, and keep the oil level up there.

 

Why the difference in pressure between when accelerating and cruising I have no idea. I can't see how there could be that much resistance in the galleries to make a whole heap of difference. As you accelerate hard through the gears, at higher RPM's I'd expect there to be a slight presure drop due to demand/delivery issues. Is your guage electronic or one of the 'Pipe' types? If it's electronic perhaps it's voltage related .

 

As for point 2.) You've got to be wrong. It's pure snake oil being sold by a crook. Actually while I know that people like pulling wheelies It's always seemed a bit pointless to me. Any energy you waste lifting the combined weight of bike and rider into the air is energy not available for making the horizon come towards you faster. S'OK if you're on a machine with ludicrous quantities of HP but on a poor, wheezy old thing like a Guzzi it seems a bit counter-productive.

 

Pete

[Ryland3210]

Why the difference in pressure between when accelerating and cruising I have no idea. I can't see how there could be that much resistance in the galleries to make a whole heap of difference. As you accelerate hard through the gears, at higher RPM's I'd expect there to be a slight presure drop due to demand/delivery issues. Is your guage electronic or one of the 'Pipe' types? If it's electronic perhaps it's voltage related .

 

As for point 2.) You've got to be wrong. It's pure snake oil being sold by a crook. Actually while I know that people like pulling wheelies It's always seemed a bit pointless to me. Any energy you waste lifting the combined weight of bike and rider into the air is energy not available for making the horizon come towards you faster. S'OK if you're on a machine with ludicrous quantities of HP but on a poor, wheezy old thing like a Guzzi it seems a bit counter-productive.

 

Pete

 

 

Point 1. My guage is the mechanical type. I was surprised at the slight drop during accel as well. I suppose there is more oil consumption at higher RPM's, but the pump's flow rate increases as well. The difference might be ordinarily be pressure drop in the filter as flow increases, but then the relief valve is after the filter, so I'm puzzled too. It's only a few psi, so no worries, but it is strange.

 

Point 2.

If I were me, I wouldn't trust me either.

[Skeeve]

Actually while I know that people like pulling wheelies It's always seemed a bit pointless to me. Any energy you waste lifting the combined weight of bike and rider into the air is energy not available for making the horizon come towards you faster. S'OK if you're on a machine with ludicrous quantities of HP but on a poor, wheezy old thing like a Guzzi it seems a bit counter-productive.

 

Pete:

 

You're absolutely right, wheelies are pointless. So's bowling. So are a lot of other things people do. So why do they do'em?

 

'Cause they're fun!

 

Of course, dirt bikes are made for wheelying, so there's always that "plan B" approach for those who've got the ready cash and garage space to support it.

 

Ride on!

[pete roper]

Pete:

 

You're absolutely right, wheelies are pointless. So's bowling. So are a lot of other things people do. So why do they do'em?

 

'Cause they're fun!

 

You're quite right But kindly remember I'm an who rides like the grandfather of the oldest in the world .

 

Pete

[polebridge]

Finally got my pressure guage installed. It's a really nice piece and looks great. The only problem I had was getting the pressure line feed attached directly under the fuel tank. On my bike there are various cables/hoses directly in the way and I needed to bend the pressure line sharply to get in installed. It would have been easier to remove the tank completely (maybe).

 

Anyway it was fairly straight forward and easy to get in place. I think it is a valuable piece of equipment on this particular model of bike. As John has previously noted, you can actually see oil pressure DROP when applying hard acceleration. It looks like I will be installing one of Roper's sheets as soon as I can locate one.

 

Being able to monitor oil pressure on this bike has been a real eye opener. I've seen the light so to speak (the oil pressure light that is and I do not wish to see it again).

 

I have a question for John (or anyone on the board who can help) about oil pressure and his experience with the V11. On my bike (Coppa Italia) pressure reads about 80 psi when I first start the bike cold. After it gets completely warm it will drop to around 40 psi at idle and stay around 60 psi when just cruising aound (probably about 3K rpm).

 

Does this sound normal?

 

Thanks.

[raz]

I have a question for John (or anyone on the board who can help) about oil pressure and his experience with the V11. On my bike (Coppa Italia) pressure reads about 80 psi when I first start the bike cold. After it gets completely warm it will drop to around 40 psi at idle and stay around 60 psi when just cruising aound (probably about 3K rpm).

 

Does this sound normal?

The OPRV is rated 55-60 psi. John mentioned 80 psi but I think that was for a much shorter time. What weight oil are you using?