Castrol full Synthetic auto oil in a Guzzi?

[dlaing]

I am getting more confused.

Thanks for the post Pete.

I had no idea Friction Modifiers were bad for dry clutched machines.

From Mobil's FAQ:

"Can I use Mobil 1 15W-50 in my bike, just like I use in my car? Mobil 1 is Mobil 1, right?

 

Mobil 1 for cars and Mobil 1 for motorcycles are markedly different. Every oil is a balance of benefits. Mobil 1 Tri-Synthetic™ Formula for cars has been developed specifically to satisfy car manufacturers' needs for increased fuel economy and low emissions.That's why new cars come with friction-modified, low-phosphorus 5W-30 motor oil. The low viscosity and the friction modifiers help fuel economy. The low phosphorus levels help protect catalytic converters. "

So no, you should not use automotive Mobil1, nor Castrol GTX, nor Syntec, nor most automotive oils....DRAT!

 

So I guess it is motorcycle only, with a few exceptions like Amsoil.

 

And thanks Gthyni for the post about the Motul 300v.

I have used their 5100 a few times and seems to burn more quickly than the Maxum semi-synthetic motorcycle oil that I have used.

Perhaps the 300V will do better.

[Guest John T]

This information does not apply to the 15-50 oil. It is not friction modified as regulations only call for it in the lighter oils. No car manufacturer calls for 15-50 oil. The trend is for lighter and lighter oils in cars. 0-30 and even 0-20 is required in many cars today.

 

If the bottle says "energy conserving" it is friction modified. M1 15-50 does not have this on the bottle.

 

Also, M1 wants to sell MC oil. Most bikes have wet clutches and don't like friction modifiers. Call and talk to a M1 tech and tell him you have a dry clutch bike and they will say you could use 15-50.

[pete roper]

The need for super-lightweight oils in many modern vehicles is, I believe, mainly a result of their having many long, complex oil galleries and delivery paths within the engine. Most engines nowadays are double overhead cam units with the cams running directly in the head castings and the cams being retained by caps. In the case of a straight six with it's oil pump located at the front of the block it will take a fair amount of time for the pump to deliver sufficient oil to the last cam bearings at the back of #6. Add in cold weather, tighter machining tollerances (Smaller gaps for the oil to be pushed through etc.) and a *traditionally* formulated multigrade and it can take a fair while for oil to get to these remote bearings.

 

The lightweight oils have a much higher low temperature flow rate so they can be delivered much quicker when the engine is cold helping prevent boundary lubrication occuring. The downside is of course that drain-down when hot is quicker and more complete than with a higher viscosity oil. it's swings and roundabouts really. Because of the bleeddown issue though I can see the attraction of using a synthetic in those sorts of applications as they do offer better start up protection as the residual film strangth is stronger.

 

With refference to a Pushrod Guzzi engine though??????? All the oil galleries are really short. Check out how quickly your oil pressure warning light goes out when you hit the starter? Take off a rocker cover and start the engine and watch to se how quickly oil is delivered to the rocker gear? IMHO the extra expense of a synthetic simply isn't warranted.

 

The energy conserving nature of thinner oils also has to do with losses due to friction of the oil, both internally and in the delivery paths, once again with short galleries the savings will be minimal compared to a large multi-cylinder engine.

 

As for the suitability of modern car-type oils? Any modern oil is so superior to what was around when the engine was designed in the early '60's it will do fine. Like a car engine the clutch is not incorporated with the engine and neither is the gearbox a pressure fed item that shares the same lubricant as the engine like most modern motorcycles. If you think of your Guzzi as a close equialent to a semi-commercial rotary hoe or a small petrol driven excavator you are probably closer to the mark than looking at modern cars or motorcycles

 

Pete

[Guest John T]

Pete,

 

You may be right with regard to the old round fins that don't produce much power....in those applications any old oil will do.

 

In the newer square heads, most notably the sports, and mostly the ones that have been hotrodded, a good synthetic just fits the bill. (why does Guzzi spec syn. oil?) When one spends alot of money on a bike and saves a few bucks on oil...well...do what you want.

 

I like the fact that when stuck in traffic or when beating the snot out of my bike, the best oil I can get is protecting my engine. Sometimes it just feels good to put the best in. (Bikes and oil are a hobby)

 

Your point on the thinner oils in cars is very valid, but the fact that these engines are water cooled and don't swing much temp wise really points out that any thin oil will do. (not turbocharged cars though)

Also, carmakers will do anything for better gas mileage and thin oils help here.

 

In the end, put whatever you want in your engine, I do! (currently Redline through out the bike)

[pete roper]

Crappy old roundfin LeMans= 848cc & 52 rear wheel BHP stock.

 

V11= 1054cc & 78-80 RWBHP

 

So the new engine is 20% bigger and produces 30% more power. Extracting more out of the V11 motor is costly and time consuming whereas the earlier models were in such a low state of tune that you could prize more out of them by doing not a lot more than waving a magic wand at them . Needless to say that's what people did, (and still do.) and at that time synthetics weren't available. In reality though none of them, new or old, produce anything more than 'Bugger All' power.

 

My horible little hot-rod was dynoed on what I suspect, (but don't care!) was a slightly optimistic Dyno and produced 84 RWBHP @ about 9,750RPM from 891cc which I thought was pretty bloody impressive! The problem I had was that when run at that speed it torched it's big ends. Why? Because at that speed the oil pump started cavitating. And I'm sorry, it doesn't matter a tinker's cuss what oil you use if it ain't getting to the pump

 

I'm certainly NOT trying to stop people from using synth. What people use is their own afair. I do think though it is important to debunk a few myths though.

 

As to why Guzzi recommend synthetic? Well, they are selling a product into a *performance* market, (as are Porche.) where the customer wants to believe that they are buying some sort of specialist, performance machine that needs *Special Stuff* to keep it running right. It's all part of the 'Toss-pot' Factor that is important to most of us in one way or another, (I'm no exception .). People are hardly likely to be impressed if Guzzi said "You can run your new V11 Sport on fermented rhinoceros semen if you like, but used chip fat is cheaper." are they?

 

Pete

[jrt]

fermented rhinoceros semen

How much is that per gallon?

[docc]

Lubricity, retention of viscosity and the multitudes of intensely technical features aside, synthetics do have one characteristic I would find beneficial in a big twin.

 

Sythetics have almost zero evaporative loss. That is to say they do not vaporize under heat and pressure like petro oils. The V11 Sport tends to gather a good bit of oil in the airbox from the crankcase venting under high rpm/spirited riding. I'm betting a synthetic would eliminate this misting. In the stock air box the temperature sensor is just by the vent and , after a bit, the whole area is pretty oily. Less of this mess would be better .

[belfastguzzi]

Less of this mess would be better .

Are you referring to the previous post?

 

But anyway Docc, I think that you are clutching at straws now. After all, this is the technical diagram of what MG are careful to recommend be used in their motors:–

[Steve G.]

Like I said, you guys put bunker crude oil in yours, I'll put the best in mine. Everybodys happy.

Oh, and ignore everything that the manufacturerer of this machine recommends, any kind of oil will do, and, oh yeah, that break in procedure, the regular maintenance, greasing the u-joints, well we know better.

Ciao, Steve G.

[Mike Stewart]

Come on guys,

 

Earl is Earl, dino vers. syn. is about the same as long as it meets the criteria. I use Mobil 1 just so I do not have to change the oil as ofter (just like the car manufactures). 4000 low miles between oil changes and I am at bless! Can you say all temperture?

 

Mike