RGS gauze filter

Re5Guy

Re5Guy

Junior member
Location
New Zealand
Hello all,

I have just done my first oil change on my RGS Corsa now it is going properly at about 500kms. I thought I should check the gause filter as well.

It was coated in a funny cotton like covering. Now that was a surprise and a worry and got me wondering what the hell had been in the engine and how I missed it!

However I did a search and found this from Sproket in 2008 talking about the RGS "the finer gauze in the sump strainer can very often react after a change of oil (if you dont remove and clean it) to develop a cotton/furry like coating on that gauze".

Well that's a relief, no shop rags left in the engine after all, but what causes this? It sounds very strange.

cheers

Tony
 
correct its a reaction to the change of oil brand, there is no definative way to say what first oil and then what replacement oil will give you this problem, but you have had a lucky escape, since the cotton fluff will starve the engine of oil and the first to suffer is the cam bearings right hand side/exhaust, thankfully this is very rare, I have seen three such engines two of them here, all of them 120's, (one was a Jota 120) and heard about others from all corners of the planet, the 180 can still be affected, but is less risk as the strainer is a courser mesh, do you know what oil was in it? you obviously know what you installed. There are dealers worldwide who say this is bollox as they have never seen it, but then ?????? did they clean the strainer???? an engine failure (that they might have repaired) ??? they would never admit to their being fluff blocking the oil return in the strainer would they, The 120 Jota was a pal, who I recovered with a seized engine, he was riding 180 miles to get home from having had a perfectly good bike "routinely serviced", he made it 165 miles, I insisted that we dont touch it, but take it back and witness him dropping the exhaust and strainer, when it came out, he tried to turn away and hide it, rub it clean, but he wasnt quick enough, he agreed to pay for labour, if Paul paid for parts, I was not happy with that, but hey ho its not my bike, I would not have allowed him to even repair it, many photos and audio would have stood up in the county court quite well!

What you must do is several oil changes using the same brand of oil, do something like 100 miles and get the motor nice and hot, drop the oil, clean the strainer with petrol and go again, do it at least two times, three would be better, over the top??? remember what my dear departed dad always told me "oil is cheaper than bearings" and yes the bleeding exhaust is a right pain in the arse, use that oil brand forever. NEEDS DOING
CLEM
 
I sold Maurice a 120 Jota in bits, he rebuilt it and realised it was getting too hot, the oil cooler was full of that stuff. Weird.
 
"Would it be brand, or type, of oil do you think Clem? It would be good to know what the change actually was from and to"

dont know the answer, but would love tp have concrete evidence of what oil make and model was first in and then the type in, at the change. I could then send details to an expert(s) at oil manufacturers and see if a result can be obtained.
I dont understand how this has never occured (to me) in my lifetime on any other type of engine both petrol and diesel, engines from 15cc right up to 27,000cc. I have never come accross it on any engine anywhere, except Laverda triples.
CLEM
 
I remember a tale in LVV regarding Mr Ray Sheepwash ...... ( ex ILOC Chairman ) ....... who had some sort of problem with his Jota 120 ..... dropped exhaust and found filter blocked as a result of four or five ..... ( his estimate if I remember correctly ) ...... oil changes but NO examination of the filter ...........
I believe Mick Hart ...... ( another ex ILOC Chairman ) ...... was present to witness this ..... which caused Mr Sheepwash no little amount of embarrassment apparently .........

As a 180 degree type of guy I always wondered how a filter could end up like that , even after four or five missed checks ........ mine was always checked every other change , and was always completely clean ......... but reading this it seems things are a little different as far as the 120 is concerned .......


As far as brand of oil is concerned , I remember Texaco Havoline 15W 40 leaving a black slimey deposit on the engine internals ...... don`t know if it actually did any harm , but it looked horrible ...... so I steered clear of that particular brand from that point on ..........
 
This is an interesting and slightly worrying thread. My RGA Sprint has been drained of oil, but I've yet to delve into the oil strainer. I'm wondering if there's a solution, as I have no clue what oil's been used in it, even recently. I have been planning on using a semi-synthetic oil, along with an external mocal spin on filter body and cartidge filter. Flushing oil would have been fine to use, if it was a dry clutch but if anyone can suggest a solution, I'd be keen to hear it.
 
It really is a bizarre anomaly. Clearly a chemical reaction between some additive/s used in different oils. Why the 120s are the only ones affected is even more puzzling. The gauge of the mesh seems to be the only significant difference.
 
Ok, well this could be a can of worms that's been revisited.

I have no idea what oil was originally in there, but it had been in there for 30 years or so. I had a cheaper Castrol 20-50 oil in it because I was always planning to do a very short oil change. It is period correct for the bike and I run other classics on it, so I will stick with it instead of changing it up like I was planning.

I have cleaned everything up and put the exhaust back on (well sort of, I've spotted one of the exhaust clamps has a crack in it :cautious:).

Coincidentally I was going to remove the rocker cover because it was leaking, this became even more relevant following Clem's comments about oil starvation to the cam bearings. I can report that there was still lots of oil up there so fingers crossed....

So get the exhaust clamp sorted, a new rocker cover gasket and then I have multiple oil changes to look forward to. YAY!!!
 
Of course, 180s are subject to the same affliction, as are all other bikes.
Any stories of engine damage linked to this fluff? If not, better to get rid of that oil strainer.
Paul
 
Way back in the 80's the oil filters on some industrial sewing machines suffered the same afliction and it was found that some oils were comtaminating the filter in the same way. The problem was fixed by the manufacturer by changing the filter material from some sort of brass to stainless steel.
I've seen some fine filter sleeves slipped over the steel coarse filter on RGS filters, these I remove and run the bike without.
Regular oil changes will keep the engine clean.
Without starting another oil thread, I've run my SFC 1000 on Penrite 10 tenths oil since running it in from new, and after some quite considerable mileage checked the bird cage filter, it was as if it had just come out of the new parts bin, the engine internals all looked good to. The same bike now has over 90,000 km on it and the engine has never been apart, still runs well and doesn't burn any oil.
Based on this experience I run all 6 of my Laverda's on synthetic oil.
 
The fine mesh filter is standard on the RGS series engines, and may well be made of brass with a soldered seam. I've never experienced the fluff phenomenon but interesting to read of a similar issue on industrial sewing machines. Maybe Clem hasn't been hallucinating after all 😂
 
Never owned a 120 , but I`m assuming it has a similar sump filter / strainer secured by three studs as on the 180 , but with a finer mesh ........

Does the 120 have a higher rate or volume oil pump ? ........ The possible combination of that , and maybe the more restricted mesh on the filter , would be the only differences I would think ......... apart from the firing order of course .......... maybe the answer lies within a combination of those things ..........

With the 180 , the routine I followed was an oil change every 1500 miles .... ( as recommended by Moto Laverda ) ....... plus a check of the " filter " / strainer every 3000 miles ........... Esso Extra 20/ 50 is what went in .......... Nowadays it would probably be Silkolene semi 10 /40 .........

As Clem mentioned , removing the downpipes is a bit of a pain ...... especially when each inspection revealed a squeaky clean filter / strainer ........ but as Laverda said in their handbooks ........ regular attention to oil changes and filter inspection will remove the need for any form of engine repair ........ ( or words to that effect .... ) ........



BTW ..... talking of over optimistic claims being lost in the translation .......

Does any one remember the news announcement issued by the Zane publicity department regarding the launch of the new range of 668 twins ?

The Italian / English translation was full of phrases like ...... " restarting the Laverda with great affection " ........

.......... and that Moto Laverda was about to ....... " fling it again internationally * .......


It was a little like a notice you might see in an overseas hotel ..... " All the drinking water has been passed by the management ... " ...... or " Our receptionist will bend over backwards to accommodate you ... " .............. but much funnier ...........

Wish I`d kept it ...........
 
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I’m going to put my twopenneth in- I believe that any fibrous coating/ pickup on the strainer has either entered the engine from an external source - broken up air filter, workshop blue paper, etc or it must originate from the motor itself. The clutch plates are fibrous and of course wear and will block filter strainers- I have seen this many times. Less obvious is nylon, rubber, silicone or paper from gaskets, cam chain tensioners etc that accumulate in the mesh.
I do not believe it has anything to do with-incompatible oils creating blue fluff. Vehicle manafacturers build engines for use around the world- they know people will use a locally sourced oil- they stipulate a minimum grade only,not a particular make. Oils are blended to be compatible unless stipulated- Castor based oils for example .
If mixing of motor oil produced this mythical fluff- surely manafacturers would be aware of this ? Well there not!
Methanol turns oil milky ( as does water) and Castor mixed with non castor forms jelly like blobs that cause merry fuck- and I have seen that.
Guzzi shop in London used a mislabelled bulk barrel of hydraulic oil on two engine oil changes ( Rock oil were the culprits) this blew the motors up as the mix/ heat caused the oil to set like grease.
If you’ve got a fuzzy strainer, I reckon it’s clutch plates fibre.
 
I disagree with all of that Mr Exmoor Beast, the reason, it happens 80 to 150 miles after an oil change, in EVERY SINGLE CASE that I have come accros. its something to do with the residues of the existing oil, mixing with the new oil and creating this dreaded fluff which is NOT BLUE, its very black in fact, but possible to see lighter colour in the fibres. it is also unique to the 120 degree Laverda triples, never seen or heard of it before in any engine, until a moment ago regarding sewing machine oil. never seen a 180 with it, but it probably does happen. some 180 owners have fitted 120 strainers, those with external oil filters will never see inside the canister, and if they block (usually) there is a by-pass route internally to save the motor. 750's have brass soldered gauze, triples have steel, does this change anything? as in the stitchers?
CLEM
 
CLEMTOG said:
I disagree with all of that Mr Exmoor Beast, the reason, it happens 80 to 150 miles after an oil change, in EVERY SINGLE CASE that I have come accros. its something to do with the residues of the existing oil, mixing with the new oil and creating this dreaded fluff which is NOT BLUE, its very black in fact, but possible to see lighter colour in the fibres. it is also unique to the 120 degree Laverda triples, never seen or heard of it before in any engine, until a moment ago regarding sewing machine oil. never seen a 180 with it, but it probably does happen. some 180 owners have fitted 120 strainers, those with external oil filters will never see inside the canister, and if they block (usually) there is a by-pass route internally to save the motor. 750's have brass soldered gauze, triples have steel, does this change anything? as in the stitchers?
CLEM
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So why is it unique to 120 Laverdas & not every vehicle in the world? Piet, Alan Bell and Toddy must know of this phenomenon.
The sewing machine story involves changing the gauze from brass to stainless steel to prevent fluff build up- couldn’t be cotton fluff by any chance?
 
Just to help (or not) the discussion I can say that in my case...
- the engine has never been apart to the best of my knowledge, done 13,000km
- I carefully inspected the inside of the engine with an endoscope, it was very clean inside (like looked "new" clean).
- I have replaced the clutch plates with new ones and this was the first oil change since installation.
- the air filter is new and not degrading.
- no idea what oil was in it, but now using a 20/50 mineral oil.
- the fluff looks black to me

cheers, Tony
 
CLEMTOG said:
I disagree with all of that Mr Exmoor Beast, the reason, it happens 80 to 150 miles after an oil change, in EVERY SINGLE CASE that I have come accros. its something to do with the residues of the existing oil, mixing with the new oil and creating this dreaded fluff which is NOT BLUE, its very black in fact, but possible to see lighter colour in the fibres. it is also unique to the 120 degree Laverda triples, never seen or heard of it before in any engine, until a moment ago regarding sewing machine oil. never seen a 180 with it, but it probably does happen. some 180 owners have fitted 120 strainers, those with external oil filters will never see inside the canister, and if they block (usually) there is a by-pass route internally to save the motor. 750's have brass soldered gauze, triples have steel, does this change anything? as in the stitchers?
CLEM
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The stuff I've found usually resembled cotton wool. Luckily, not enough to hamper oil flow. No further contaminants found either.

The course sand-strainers of the early triples wouldn't catch it, reckon it would even pass through the 500 and 750 "filters" unnoticed. Late 180s had a very fine brass mesh, the same as the 120s. The 120 strainers are only about half the length of the earlier versions though.

piet
 
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