MRC Forum- brought to you by www.morini-riders-club.com Member: g7AW3f

Sorry to bring up yet another oil thread!

I recently returned to the USA and am finding it difficult to source a suitable oil for my 350 Sport. Can anyone recommend a low grade (pre SJ) non-synthetic blend 15W-50 or similar oil? I found 20W/50 Valvoline SG/SJ "Motorcycle" oil at AutoZone: Has anyone found a source for a more appropriate oil for the 350 motor?

Thanks!

Daniel

You're going to have a tough time finding anything below SL grade, since SH and earlier are classified as "obsolete."



You can buy Swiss Motorex 15W50 SG in the USA, but good luck finding it locally. You'd probably be better off ordering it online:
http://www.motorexusa.com/products/atv/ ... portmax-4t

Spectro makes a 15w50 SL, but it's labeled "EXPORT ONLY" on their web site:
http://spectro-oils.com/spectro-silver-4/

Surely, as it has a dry clutch, you can use any oil you like. My view is that with limited HP, even a wet clutch doesn't need special treatment.

I've always used Rotella in my wet clutch bikes, or was it Guzzis(dry clutch), I cant remember. I think Rotella has low friction additives so it wouldnt make the clutch slip. Not an issue for Morinis, or Guzzis, wth was I using it?

Are you after something with zddp designed for flat tappet motors? There is a zddp after market additive on the market. I remember reading something about also using low detergent oils in older bikes since they dont have paper filters and you want the particles to settle, not circulate. Let us know when you figure it out!

"..
Motorcycle usage[edit]
Though marketed as an engine oil for diesel trucks, Rotella oil has found popularity with motorcyclists as well. The lack of "friction modifiers" in Rotella means they do not interfere with wet clutch operations. This is called a "shared sump" design, which is unlike automobiles which maintain separate oil reservoirs - one for the engine and one for the transmission. Used oil analysis (UOA) reports on BobIsTheOilGuy.com have shown wear metals levels comparable to oils marketed as motorcycle-specific."

Tanshanomi wrote:You can buy Swiss Motorex 15W50 SG in the USA, but good luck finding it locally. You'd probably be better off ordering it online:
http://www.motorexusa.com/products/atv/ ... portmax-4t

Thanks! There are four relatively local dealers in the metro Atlanta area. I will try them tomorrow.

The issue is not the clutch but rather the detergents and additives in modern oils that do not always work well with old oil seals and other old-spec bits in the 350 motor. There was an exhaustive thread on it a few years ago, but I forget whether it was on this forum or another.

I think it is a waste of money to use anything other than Castrol GT oil,,, it is what The Morini factory cast into the oil sump plug of my bike and works just great....

15w-40 works just fine except in the very hottest of weather or in the case of a very worn engine.

Robert

tobydmv wrote:I've always used Rotella in my wet clutch bikes, or was it Guzzis(dry clutch), I cant remember. I think Rotella has low friction additives so it wouldnt make the clutch slip. Not an issue for Morinis, or Guzzis, wth was I using it?

Are you after something with zddp designed for flat tappet motors? There is a zddp after market additive on the market. I remember reading something about also using low detergent oils in older bikes since they dont have paper filters and you want the particles to settle, not circulate. Let us know when you figure it out!

"..
Motorcycle usage[edit]
Though marketed as an engine oil for diesel trucks, Rotella oil has found popularity with motorcyclists as well. The lack of "friction modifiers" in Rotella means they do not interfere with wet clutch operations. This is called a "shared sump" design, which is unlike automobiles which maintain separate oil reservoirs - one for the engine and one for the transmission. Used oil analysis (UOA) reports on BobIsTheOilGuy.com have shown wear metals levels comparable to oils marketed as motorcycle-specific."

Rotella T 15w40 is my "fleet oil" used in all of my vehicles including the Morini 350 K2.

My 1974 Sport handbook (English version) lists only Castrol GTX with a change interval of 4000 Km, whilst my 1978 500 handbook (Italian version) lists Castrol 20-50 XL (4000 Km) or Castrol RS (8000 Km) and also Castrol GTZ 10-40 (4000 Km) for winter use.

Later handbooks list Sint Agip 2000, a 10w40 semi synth for year round use.

I thought I would post the under-seat label from my US model K2, a 1985 bike:



As you see, it recommends a 20/50 oil (or "sintetyc"!). I have been using Miller 20/50 semi-synthetic over the summer and I am intending to use a standard 10/40 semi for the winter, when it probably won't see a lot of use anyway, depending on the weather. I tend to give up when cleaning time starts to exceed riding time! This is the oil strategy I have been using for my Bonneville and Trident the last few years and it seems to work for me. I like to think the Bonnie is a bit easier to kick over in winter with the slightly lighter oil, but that's probably in my imagination! With its 11:1 CR, the 350 Morini isn't much easier to kick over than the 750 Bonneville

Incidentally, I have never had any clutch slip problems with wet clutches and semi-synthetic and I do wonder if this is a bit of a myth. Very little oil actually penetrates inside the clutch plate stack. Not an issue for the Morini anyway!

penman wrote:I thought I would post the under-seat label from my US model K2, a 1985 bike:
Incidentally, I have never had any clutch slip problems with wet clutches and semi-synthetic and I do wonder if this is a bit of a myth. Very little oil actually penetrates inside the clutch plate stack. Not an issue for the Morini anyway!

More a question of using car spec. oils laced with friction modifiers in a wet clutch motorcycle. Having said that, the only problem I've experienced was with the 'wrong' *full* synthetic in a Gilera Nordwest with a starter sprag clutch already past its best.

I've been using Halfords 10w-40 semi-synthetic Motorcycle oil recently, though I may source a 10w-50 for running the project on in the summer. After having to do top notch motorcycle spec. full synthetic oil changes on the basis of tens of hours, rather than 1000s of miles, on the YZ450F and 350SXF I don't baulk at spending a few quid on oil. The Voxan had to be fed very special, specific, 10w-50(Voxan) full synthetic made by Motul or Castrol RS10w-60.

Does it really say 1mm for valve clearances?

Yes, it does. It's repeating the error in the front of the 1974 handbook. When you actually go to the section on adjusting valve clearances it says 0.1mm

MickeyMoto wrote:Does it really say 1mm for valve clearances?

Yes it does! And it backs it up with 40 thou. I can only assume there is a decimal point issue here, I think 40 thou would be a bit on the rattly side!

Another label under the seat tells you to adjust the idle air screw to obtain a specific CO reading. OK, adjusting the idle mixture screw will come to the same thing, but it's a bit sloppy calling it an air screw when it actually controls petrol on these carbs. A case of "lost in translation" maybe.

I think that label is wrong about the quantity of fork oil as well; the Marzocchis on my 350K needed 220cc according to the chart in the Marzocchi manual here: http://www.ducatimeccanica.com/marzocch ... chi_25.htm

I use 15w/40 fully synth 'motorcycle spec' oil in my Morini, partly because it's the same stuff I use in my modern Yamaha and partly because of the sustained high revs the Morini tends to be run at.

It seems to work ok.

So far...

I have had problems using 'car' oil in motorcycles with wet clutches, but only on a bike that was making over 125bhp at the back wheel; the clutch became very grabby and unpredictable until the oil was changed and the plates cleaned. We decided the friction modifiers were making it slip until the lever was all the way out and the plates fully compressed together, but that was just a guess. I've never had the same problem when using fully-synth JASO spec motorcycle oil on other motorcycles with similar power outputs.