Engine oil change

[Guest gavin]

I know its very subjective topic, especially when thinking about type of riding, but I would like to get a feeling about how often the engine oil should be change.

In theory with modern semi, or fully, synthetic oils and without the added shearing stresses of a gearbox I think the stated 6000 miles should be safe.

I'd liked to hear what you guys think as I've always changed my jap bike oils at 3000 mile intervals (my old Z1 has 115,000 miles up and is still running sweet)

[zebulon]

On the last v11 Guzzi told to change Oil every service so every 10 000 km (6200 Miles) but in the facts all the real goods Guzzi mechanics in France says it is better to change it every 5000 km (3100 Miles).

 

For my daytona rs i change it between 4000/5000 km (so less than 3000 Miles)because i use the bike only for making long trip or sport trip

The bike only had 40 000 km since 1999 but it rides fine.

[RichMaund]

I believe the 6k mile interval is some sort of marketing gimmick.

My valves and TB balance won't stay in adjustment that long and the bike would run like crap if I let everything go that long.

I check valves, set TB balance and change fluids every 3k miles. I change the filter every third change. I use synthetics exclusively. This interval is more in keeping with what Guzzi used to recommend and reflects, in my experience, a reasonable amount of use that the bike will run well between adjustments.

 

Some of you may think I'm nuts to leave all that "contaminated" oil in the filter between changes. But it is a relatively small volume. I change it frequently enough that the left over oil in the filter is still good by Guzzi's reconing. And the filter is plenty large enough to do it's job for three changes. Heck, that's how long the old style shorter filer was good for. This one should be no different. Besides, as tricky as it is to remove and replace the manhole cover below the filter, better to do it every 9k miles and save much wear & tear on it!

[callison]

I've given up on the manhole cover. The filter wrench never seems to get a good enough grip to remove the filter. Doesn't matter if it's a metal or plastic one, UFI or some other. Nowadays, I just remove the pan and wipe the bottom out while I'm at it. I've had one Guzzi I did this on for four years before the pan gasket got stiff enough to require replacing. YMMV.

[dlaing]

I love lube threads

What it all boils down to is what is most cost effective in terms of time and money.

I can hear the difference between the engine running on dirty oil of only 1000 miles and a fresh oil change. So the viscosity does brake down enough to create more noise rather quickly, and presumably more friction and wear.

So what is going to break down?

Rings, Cylinder walls, valve train, Bearings, oil pump?

So say you need a new top end every 50,000 miles and a new bottom end every 100,000 miles. Perhaps that is $1000 every 100,000 miles. I am just guessing. The point is that the cost should be weighed against the cost of oil changes.

 

There are lots of strategies for oil change scheduling.

You can change the filter every time or every other time.

You can use dinosaur oil and change it frequently.

You can use automotive or motorcycle oil.

You can use synthetic oil and change it less frequently.

For the most part, you get what you pay for.

Synthetic Motorcycle Oil is arguably the "best" stuff to put in, but also the most expensive.

Automotive synthetics are moderately priced, available everywhere, and will last a long time.

 

Say you are low budget and do an automotive synthetic oil change every 10,000 miles costing $20 per oil change times 10 oil changes over 100,000 miles, which totals to $200 in oil changes. After 100,000 miles you should have money left in the bank for an engine overhaul with Carillo rods and FBF pistons.

Now if you had taken exceptional care of the bike and changed the Agip Motorcycle synthetic every 2500 miles, and used the OE oil filters, your engine will be in better condition, but you will have spent $2000 in oil changes,!!! Nothing left in the bank!!! But your engine MAY go another 100,000 miles.

Moto Guzzi recommends a happy medium between these two strategies.Nothing wrong with that. The Agip oil can probably go 10,000 and still be ok, but you'd be taking a chance.

Personally, 6000 miles is fine.

I think automotive synthetics like Mobil One and Castrol Syntec, are the best deal out there. Just don't expect to pay $4/liter and have it protect well for more than 6000 miles.

I think they are only good for about 5000 miles. They do not have the extra protection that motorcycle synthetics have nor the durability of oils like Amsoil or Red Line.

Now if you can get a good deal on Motorcycle sythetics, go with that.

I found Motul synthetic for $25 for four liters. I feel very comfortable running it for 6000 miles.

Another strategy would be to use dinosaur oil like Castrol GTX and change it every 2-3000 mile. It is more labor, but cost effective.

The bottom line is that you can spend too much on oil changes, or you can spend not enough and pay Moto Guzzi later for new parts.

I don't know of any study of oil changes versus engine repair, but I suspect if you use your common sense everything will be alright.

[Guest gavin]

Thanks all, just as I thought - lots of good theory and all erring on the side of caution.

 

I'm going to go to 3,000 mile oil changes, filter every other change and use semi-synthetic Castrol GPS 10w40 for extreme temperture.

The reason for this choice of oil is that I spoke to Castrols tech department (sad I know!!) and for an air cooled engine this is more durable over a wider heat range and the viscosity is higher (water cooled motors maintain a steady temp).

 

The guy made good sense and was actually recommending a cheaper oil than the fully synthetic stuff - therefore he sounded genuine (.....?).

As mentioned before my Z1 has done over 100,000 miles and that only ever had Castrol GTX, albeit very regulary so I think a lower milage change is good.

 

We'll resume this discussion in 85,000 miles time and see what happens!!!!!!

[Janusz]

For my daytona rs i change it between 4000/5000 km (so less than 3000 Miles)because i use the bike only for making long trip or sport trip 

The long trip is the least taxing on the oil. If you do mostly long trips you might as well prolong the intervals between oil changes but for sure not shorten.

 

It always amuses me when somebody doubts a factory official recommendation. Look, Moto Guzzi uses and recommends a fully synthetic oil in new bikes changed every 10,000 km. You will never make a mistake if you follow that. I challenge anybody to show ONE documented case when following manufacturers advise caused a failure.

 

The ONLY conclusive and sure thing to PROVE the best oil change interval is an oil analysis. Based on these most big OTR rigs change oil every 100,000 on average and run for milions of miles on modern synthetic oils. On my diesel car I change a quality synthetic every 25,000 km BASED ON OIL ANALYSIS. The engine works extremely hard, hot and at over 20/1 compression.

 

Paying a little extra or even double for a good quality real synthetic (no semi synthetic gimmic) is an excellent economy; these oil are vastly superior. And MG factory, again, recommends the synthetic (not semi) for use.

 

The oils today, all of them, are so much better then even 10 years ago that all the rules our fathers taught us about oil changes HAVE NO MERIT.

 

Our engine is a low revving (my Miata has higher redline for God's sake) traditional engine with a separately oiled and cooled transmission and clutch.

 

Of course that a statement like that : "my XYZ had oil changed every 1,000 miles and run for gazilion miles with no problem" might be true but proves absolutely nothing. Frequent changes will not hurt you at all. Only your pocket.

[Janusz]

The guy made good sense and was actually recommending a cheaper oil than the fully synthetic stuff - therefore he sounded genuine (.....?).

If you want to be a skeptical you might say that he only possibly made more profit on a cheap oil.

[emry]

Don't forget that the oil we are changing isn't actually worn out. It is just dirty. The purpose of changing the oil is to remove the extremly small particulates that are the result of the combustion process and the small amount of physical wear that takes place in the engine.

[Janusz]

That would be true only in case of older Guzzis which do not have a filter.

 

A stock filter is more then enough for 10,000 km.