The BSA A7-A10 Forum

Technical => A7 & A10 Engine => Topic started by: Alan @Ncl on 16.01. 2011 23:54

Title: Filter in Oil Feed Line
Post by: Alan @Ncl on 16.01. 2011 23:54
As a new forum member I must first say how impressed I am by the quantity and quality of the information and discussion presented on this site. 

I have a 1957 Goldflash that I rescued as a partial machine back in 1975.  I then completely rebuilt it using parts from wherever I could get them so its not exactly standard.  For the past 15 years the bike has stood in the back of the garage, completely ignored and without turning a crank but I have recently set about returning my old friend to its former glory. 

I am now getting near the point of attempting to start the engine following this long period of total neglect.  I have provisionally dealt with some magneto and fuel problems (more of that later) but my immediate concern is with lubrication.  When I rebuilt the bike back in 1975, I made up and installed a cartridge type oil filter and located this underneath the oil tank near the centre-stand where it is hardly visible.  However, THIS FILTER IS INSERTED IN THE FEED TO THE MAIN OIL PUMP, rather than in the return (the latter seems to be almost universally the normal approach, as far as I can see in your threads).  It is interesting that back in the 70s, the advice I was getting was to place the filter in the feed but to be careful to select only a filter that did not contain any kind of ball valve or other potential restriction. I ran for years (not huge miles though) on Castrol GTX, with this arrangement, and never had any problems (except for wetsumpiing of course, if stood for long intervals). Having fitted a draincock on the sump plate this was not really a major problem; only an inconvenience.

Having recently thoroughly cleaned out the oil tank I have now been persuaded by the local classic bike guru to invest in some very expensive modern monograde SAE 40 oil (which also includes a detergent, I note).  The bike is certainly not wetsumping to any degree now and I instinctively like the idea of this nice, customised sticky grade 40 stuff adhering to those good old bushes and bearings.  However,I am worried that the added viscosity may prove problematic for the pump when pulling the oil through the filter, especially when cold.

And so to my question.  Should I ?bin? the expensive oil and go back to 20/50 or should I move the filter into the return line and retain the fancy oil (or perhaps replumb the filter but still go back to 20/50 as well)?.  Any ?words from the wise? would be much appreciated as I think the situation I have described is slightly different to those that have appeared in the past.
Title: Re: Filter in Oil Feed Line
Post by: muskrat on 17.01. 2011 08:19
G'day Alan, welcome to the forum.
                                              Move the filter to the return line, most important not to have any restriction on the feed. Oils seems to be a personal thing. I use 20/50 and add Nulon.
Bet you can't wait to throw a leg over her again after so long.
Title: Re: Filter in Oil Feed Line
Post by: LJ. on 17.01. 2011 09:45
Hello Alan... Nice of you to join us, hope you get a lot of pleasure here.

I think the thick SAE 40 oil and filter is asking a bit much, especially as you say in cold weather. I think it's best to stick with either the filter on return with 20/50 or go straight 40 with no filter and change oil regularly like I do. I agree entirely with what you say about that satisfying... "I instinctively like the idea of this nice, customised sticky grade 40 stuff adhering to those good old bushes and bearings." Spot on! when I look in the tank at 20/50 I don't really feel very confident about a watery looking lubricant when tank is sloshed from side to side. Actually I have been using XXXL50 but will go 40 when I get the next 25 litre drum from Castrol.

Just my opinion, let the oil wars begin!  *smile*
Title: Re: Filter in Oil Feed Line
Post by: bsa-bill on 17.01. 2011 10:29
Hi Alan and welcome
My thoughts oil wise, on a rebuilt motor ( sludge trap cleaned, engine flushed) 20/50 or modern oil of choice every time, but not in a motor that still has a sludge trap and oil-ways lined with engine cholesterol.
But do be careful with so called straight oils as some do contain detergent ( as you have said), detergent will release any crud to float around the system, OK this is why you have a filter but it's not designed to handle a backlog of stuff !!!

Title: Re: Filter in Oil Feed Line
Post by: brackenfel on 17.01. 2011 13:20
Hi Alan,
Welcome to the Forum.. In my limited time here I have found this to be a wonderfully informative, friendly and helpful place, I hope you find the same..

As for oil I have a very good friend who recommends 20/50 for everything but I have my doubts..

A long while ago I had a Laverda 500 and the then guru (sadly now deceased) recommended Solkolene Race Lube 40 (a straight oil with some detergent content). I bought every can I could find as it was often been sold off relatively cheaply as there wasn't much demand! I then sold the Laverda and have since used it in my Velo for years. My A10 doesn't have a filter fitted but I intend to use the straight 40 when I refill shortly and will probably also use it for the B33.. The Velo oil gets very dirty but it does have a fabric filter (in the return). I have no doubt that the detergent is removing the crud but (touch wood!) so far with no catastrophic effects....

I have a Laverda 750 which I filled with Duckhams Q20/50 and when it ticks over more slowly than it should the oil light flickers so that's getting the 40 in the Spring too..

A long time ago I was told that straight oils were best for engines full of roller bearings (inc big end) like the Velo & Lav but don't think it'll do any harm in the BSA..
Just my opinion, hope it helps..

Title: Re: Filter in Oil Feed Line
Post by: dpaddock on 17.01. 2011 17:27
I've been using 40 grade diesel engine oil in my A10 for a couple of years now. The reason is that diesel oils retain the anti-friction additives that have been removed from gasoline engine oils (those additives reportedly cause early catalytic converter failure in automobiles, and the oils have been reformulated as a result). The cam followers in the A7/A10 engine are non-rotating and need all the slipperiness of those anti-friction additives.
One can certainly add some STP or other friction modifier to non-diesel oils, but I figure that diesel engines are designed for heavy duty and the lubricating oils have to be formulated for that. So far, there are no problems.

Title: Re: Filter in Oil Feed Line
Post by: nigeldtr on 17.01. 2011 17:57
Hi Alan,

This forum is great, beats watching the tele any day of the week ? how did we cope without forums and internet!

Anyway, I did some tests last summer, gets regularly to over 30C here in central Germany and I found it didn?t make much difference SAE 40 or 50. Once the engine got hot, the viscosity fell through the floor ? oil was at about 80C (I seriously thought about fitting an oil cooler *ex*). These were straight single grade oils ? no additives. They were from a specialist supplier here and he said that a 20/50 should be better, 20 to start with and thickening to 50 when hot. Apparently there are some expanding molecule chains that get excited and thicken things up ? if this is true, to my mind, it?s the perfect solution ? sorry no pun intended. Equally, he said thick oils are fine but move more slowly so you don?t get as much quickly to your bearings to do the lubrication and cooling bit especially important from cold, should get a discussion going *whistle*

That?s my bit, feel better now.

PS Interesting info about the Diesel oil!
Title: Re: Filter in Oil Feed Line
Post by: Goldy on 17.01. 2011 18:42
I don,t think it really matters which oil you use. In the 60,s we just bought the cheapest. The main point is to change it frequently. All the best and welcome.
Title: Re: Filter in Oil Feed Line
Post by: bsa-bill on 17.01. 2011 18:58
Goldy - spot on, and there was not a lot of choice either Castrol, Shell, and a few smaller brands THEN came Duckhams 20/50 (green it was) and we should remember it was designed for motorcycles

David I think oil for diesel engines might well be more robust, amongst other considerations -higher compression rates (my last diesel car was 20:1)
but also engine oil for diesels was amongst the first I encountered with detergent, this was in the late fifties
Title: Re: Filter in Oil Feed Line
Post by: lawnmowerman on 17.01. 2011 19:19
Interesting point regarding diesel oil. I will be changing the oil in the next few weeks so I may give it a try. What grade diesel oil should I use and should it be straight or multigrade, mineral or synthetic. Also detergent or non-detergent - the PO had the engine rebuilt about 500 miles back by JB engineering so hopefully the sludge trap and all the crud was cleaned out.
A friend of mine swears by diesel oil and uses Caterpillar 10/50 - or was it 10/40.

Title: Re: Filter in Oil Feed Line
Post by: Stu55Flash on 17.01. 2011 20:19
Alan, welcome to the forum. This interesting discussion goes on at various times on various classic tractor and car forums as well!

A key consideration for which oil to choose should be the oil pump. The original pumps where built to work with 30/40 grade oils. Modern multigrades are too thin for the pump to work as intended. Compounded by further restrictions like a paper filter make the situation worse. As discussed modern multgrades have detergents to carry crud to the paper filter so there is no need for a sludge trap in a 'modern' engine. Don't know what the people making modern spec pumps, such as SRM, would recommend.

I am using straight 30 grade for winter changed more regularly than recommended to keep the sludge trap clean for longer.

Title: Re: Filter in Oil Feed Line
Post by: chaterlea25 on 17.01. 2011 23:04
HI All,
Some years ago before the "reintroduction" of "classic" straight 30/40/50 oils
It was quite difficult to obtain plain grade oils
I used to be able to get Duckhams fleetol 40 this was used in older diesel engines, then Castrol had 30 and 40 for diesels as well (RX super????)
Nowadays it seems modern diesels use very low viscosity oils and I have not seen a straight diesel lube in the British Isles for a long time!!!
dpaddock can probably still get them in the USA as I believe thyey are available there??

Nigeldtr, I dont think you are correct in your thoughts about multigrade (or we are interpreting things differently??)
Multigrade to the best of my knowledge is described like this,
It has the viscosity of the lower number (say 10,15, 20) at say 0 deg C
And the viscosity of the higher number  (say 40 ,50 ) at say 100 deg C ( I dont have the actual temp figures in my head *conf*)
It does not get thicker as the temperature rises!!

I dont claim to know how all this technology actually works *conf*
My wife has a modern Mini (BMW) which uses a  0w/40 oil, which is bloody expensive!!!!
this pours almost like water and I dont know how it works?????? *smile*

I know that SRM will not guarantee their rebuilt engines UNLESS they are run on straight monograde oil

Alan, I would recommend moving the filter to the return line, as others have said

Regards To All
John O R

Title: Re: Filter in Oil Feed Line
Post by: scotty on 18.01. 2011 00:26

Welcome to the forum..sounds like a nice project you have going there.

I've recently plumbed in an external oil filter on my A10 on the return side.
One of a few reasons for the return side location, I'm told, is that the return side of the pump has double the capacity of the feed side.
i should add that the A10 is not yet running but i have the same filter set up on my B33 and it works very well along with same 40 grade diesel oil that i use on the boat.
Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 18.01. 2011 15:16
Thanks to all of you who have replied (12 so far, which is fantastic) to the thread that I started (restarted really) on oils and filters.  Its great to have access to such expertise and thanks too for all the warm welcomes. 

A range of opinions is evident, as would be expected on a subject like this.  I was half expecting to get more ?flack? for having a filter on the inlet side!  However, from reading previous posts you are clearly a very courteous and friendly crew so perhaps I should not have worried.  That said, it does seem I am in a minority of one at present in having plumbed it this way in the past, and several of you have gently nudged me to move it onto the other side.  This would be easy enough to do as the way its plumbed all I have to do is cut into and connect the return pipe and then bridge the ends of the feed hose with a bit of 8mm tube (see picture if interested).

I am not going to decide too quickly what to do next and some of your replies have prompted me to do a bit more research on oil specs, viscosity etc. I will report back when I finally decide which route to take.

Meanwhile, can I hark back to earlier posts about exacerbated wetsumping occurring in some cases after fitting a filter in the return line. Can I ask did a consensus ever materialise about how this could happen? 

Linked to this, does anyone know what kind of pressure drop typically occurs across a cartridge filter under normal temperature, viscosity and flowrate conditions?  With a positive displacement gear pump, such as we have here, its hard to see where else the discharge flow can go except back to the tank, up to the rockers or internally back through the pump by leakage (i.e. three potential paths in parallel with oil choosing which way to go based on relative flow resistances between them). 

I suppose that if the rocker take off was plumbed on the inlet side of the filter rather than on the discharge side, then a fairly modest filter back pressure could easily divert more oil back into the engine.  I don?t suppose any of the problem cases quoted were plumbed this way but if they were, perhaps this could explain it?
Title: Re: Filter in Oil Feed Line
Post by: A10rocket on 18.01. 2011 16:46
another advantage of having the filter on the return is your pumping filterd oil back into the
tank.  Having the filter on the feed means any particals in the oil get pumped into the tank and start
 to settle in there and eventually you end up with sludge in the tank.
Title: Re: Filter in Oil Feed Line
Post by: nigeldtr on 18.01. 2011 17:36
Hello Everyone,

John, thanks for the oil info. I thought the idea of a multigarde was to be thin when cold and a bit thicker when hot. I may well be wrong, far too much chemistry or what ever it is for me.

PS I also fitted the filter in the return line on my plunger, tucks in nicely behind the gearbox.

Once the engine is run in, is it worth popping in a bit of molyslip or what ever its called?

Re the wet sumping, I think it?s probably more likely to be a worn oil pump or in the case of my SW A10, the pump was not seated correctly on the crankcase!



Title: Re: Filter in Oil Feed Line
Post by: Triton Thrasher on 19.01. 2011 05:26
I thought the idea of a multigarde was to be thin when cold and a bit thicker when hot.

Not exactly.  It thins out when hot, but not as much as a non-multigrade.

20W/50 is supposed to be as thin as a cold mono 20 when cold (W for winter).  It's as thick as a hot mono 50 when hot.  Hot 50 is thinner than cold 20.
Title: Re: Filter in Oil Feed Line
Post by: iansoady on 19.01. 2011 11:13
Once you start an oil thread it never stops....

I found this ( the best guide I've seen - from someone who spent his working life in the oil industry and rode a Commando till his unfortunate early demise.
Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 19.01. 2011 12:54
I was going to offer some comments based on the recent reading I have been doing around the viscosity issue but I think Triton-Thrasher sums it up admirably.  Also Iansoady reference article is excellent.  Its easy to see how people can get 'the wrong end of the stick' and I have certainly learned a lot these last few days.

I am now beginning to wonder what advantage monogrades could ever have relative to a multigrade that has the same upper SAE number?  At face value, it seems that with monos, we are always potentially in jeopardy during that critical cold start up period?  So why do respected authorities like SRM like us to use monos in their rebuilt engines?  There must be some arguments in its favour?
Title: Re: Filter in Oil Feed Line
Post by: nigeldtr on 19.01. 2011 17:55
Triton Thrasher,

I read something like this but you put it much more clearly!  It doesn't get thicker, but also not thinner than the 50W correct ????

I will stick to the 20W/50W for now.

Title: Re: Filter in Oil Feed Line
Post by: trevinoz on 19.01. 2011 19:51
I have said this before and will say it again.
The oil recommended in the 50s was what was available.
In the 60s when multigrade oil became widely available the bike manufacturers changed their recommendation to that product. Just have a look at the late model hand books.
The engines are essentially the same as formerly just prettied up in new cases.
They also recommended EP oils for the gearboxes which opens another can of worms.
Title: Re: Filter in Oil Feed Line
Post by: Triton Thrasher on 19.01. 2011 21:12
Triton Thrasher,

I read something like this but you put it much more clearly!  It doesn't get thicker, but also not thinner than the 50W correct ????

I will stick to the 20W/50W for now.


You have to be sceptical of proud makers' claims.  I wouldn't be surprised if hot 20W/50 is actually a bit thinner than hot 50. It may even be a bit thicker than cold monograde 20, when cold. 

My experience is with Triumphs and I say with confidence that monograde 50 is too thick when cold, to be used in Triumph twins on cold mornings in Scotland (and all mornings are cold here). Oil pressure can collapse when you rev up.  20W/50 works fine.  I've never used monograde 40 or 30, never owned a BSA Twin and do not know why SRM doesn't like multigrades.
Title: Re: Filter in Oil Feed Line
Post by: Stu55Flash on 20.01. 2011 00:31
The article on multigrade oil is fantastic but it considers the oil only not the rest of the engine. The oil technology undoubtedly  moved on but so did the engineering within the engine. This went hand in hand through the 60 and 70s. The technology developed in  iteration, I don't think you can consider any one of these in isolation to the other. The article considers the oil what about the rest of the bike engine?

Title: Re: Filter in Oil Feed Line
Post by: cyclobutch on 20.01. 2011 09:46
Do love a good oil thread.

Putting viscosities aside for a moment. My thoughts were that the monogrades were at least designed to dump the particles, and hence we have a sludge trap to collect them. The 20/50 would carry the particles around, hence you would plump for this if you'd fitted an in line filter. That of course is ignoring comments previously posted here on which of these might now carry detergents and the like.

On the viscosity front, using the 20/50 is going to exacerbate any wet sumping problems there might be of course.

We were talking on issues of preventing wet sumping quite recently somewhere here. Of my experiences:

My engine was fully rebuilt and came loaded, I think, with a monograde. I subsequently fitted a paper filter in the return line. (Fitted in the tool box btw, as the fitting instructions suggested, but which I understand might in fact be higher than is thought good here). At the same time I switched to a 20/50. The bike wet sumped horribly. I fitted an SRM bottom plate with sump plug, but as the crankcase would fill in just a couple of days I tired of the constant draining I had to do from that. So I fitted a Britie valve in the feed line. No more wet sumping.

However in pretty short order I seized the motor on the timing side crank bush. Roger at Cake Street pulled it down and rebuilt it this time. His verdict - the crank was a little tight in the bush, the oil pump body was shot. Maybe. My thoughts are that perhaps the oil pump was poor enough that the oil drained through it from the one way valve down and then the pump didn't self prime.

Either ways. The bike is now fully oil tight and doesn't wet sump a jot - this with that valve no longer in the oil line. Not sure what oil Roger has used - but I'll be checking with him.

Title: Re: Filter in Oil Feed Line
Post by: olev on 20.01. 2011 12:39
I've got one of Goffys oil filters and intend to fit it to the plunger A7.
Can anyone tell me the most elegant spot to fit the dirty great thing.
It won't go in the toolbox.
Nigel said he fitted his behind the gearbox and that seems like the go.
Photos and ideas about rooting the plumbing would be appreciated.
Title: Re: Filter in Oil Feed Line
Post by: alanp on 20.01. 2011 13:42
This jogged my memory re 20W-50 oils and wet sumping. I've got a filter fitted on my return line and use 20W-50 oil and since November when she was kept in the unheated garage it has wet sumped 1 1/2 litres of oil and that's with a new SRM pump. That's approx 20 ml per day. Guess that's the 20W telling me it's thinner in these conditions than 50 grade and will sneak through.
This means that during the riding season with at least one run a week it's of no consequence and I haven't ever noticed any problems with starting or running, so I can't see me bothering to fit an anti-sumping valve, unless I get too bored waiting for the better weather that is!
Regular bike users are probably worrying unduly over this.
Talking about waiting for the better weather, a friend of mine couldn't wait and ended up trashing his gorgeous Dunstall BSA A65 on the black ice/frost down the end of his road last week. Patience my friends!
Title: Re: Filter in Oil Feed Line
Post by: trevinoz on 20.01. 2011 20:38
         Your statement that engine technology advanced throughout the '60s and 70's doesn't apply to British motorcycles.
They were still 30s and 40s designs!
Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 20.01. 2011 21:17
Just taking stock so far, it seems the monograde/multigrade debate can be crudely summarised as follows.

Ideally, oils would have constant viscosity (thickness) independent of temperature.  So on a graph of viscosity against temperature an ideal oil might appear as a horizontal line as shown below.

However, in practice, viscosity does not stay constant.  It decreases (exponentially) as temperature increase and this is true for all oils.  So if we draw a graph of viscosity (on a logarithmic scale) against temperature, we get something like the sloping lines shown on the diagram below (not drawn to scale though as this is for illustration only). 

For a monograde oil such as SAE40 we get a steepish straight line sloping down from left to right. Note this line intersects the one depicting the ideal oil at approximately the operating temperature for which it is designed (say 100 C).  The problem is that at low temperatures, this oil will be very thick so drag will be excessive and lubrication at cold start may be poor.

One answer is to use additives to help flatten the viscosity line (i.e. reduce its slope or increase its viscosity index) so that it lies nearer to the ideal horizontal line. Hence at lower temperatures the oil behaves more like an SAE10 whilst at high temperatures, continuing to behave like an SAE40.  This is basically what multigrade oils do.  Hence they have titles like SAE 10W40 to designate that they behave more like a 10W grade when cold in winter but revert to SAE40 at normal operating temperature. 

The potential advantages of multigrades are thereby evident, especially during starting and at low temperatures.  So what, if any, alternative advantage can monogrades potentially offer? I have seen it stated that:
1   They do not deteriorate (thin out excessively over time at higher temperatures) to the same extent as the multis do.
2   Monogrades are less prone to sludging since they do not contain the VI additives. 
3   They are less prone to wetsumping (important within our current context).

This makes sense to me and fills in a bit of background.  Unfortunately, it still does not definitively tell us which is best!  Perhaps the relative advantages cancel each other out so that, as some on this forum have said, it does not really matter which we use, as long as we change the oil regularly. 

Title: Re: Filter in Oil Feed Line
Post by: nigeldtr on 20.01. 2011 21:43
Hello Olev,

please see attached pictures. The bracket is mounted to the top rear engine bolt and between the oil tank bottom fixing and frame. You need to drop a vertical plate down from this plate to mount the filter head witch is roughly 2 cm offset behind the seen horizontal mounting plate. It fits in well and you can get your hand in to do it up without any great problems, The only difficult bit was bending the tight radius on the copper pipe in the return to the tank. The next filter, I will spray black ;)

If you need more pictures let me know.

Title: Re: Filter in Oil Feed Line
Post by: nigeldtr on 20.01. 2011 21:44
Other picture
Title: Re: Filter in Oil Feed Line
Post by: alanp on 21.01. 2011 10:54
Just let me extend the filter subject high jack a little bit more on the oil debate.
I agree with the conclusion that we don't know what is best for our old air cooled engines and I expect this would vary anyhow depending on how they were used re. speeds, ambient temperature, wear condition etc.
In general, it seems to me we should stay away from the 'too thin' area on the graph when the engine is hot, but what is the best method?
Those of us with oil pressure gauges can see the oil pressure falling as the engine gets hotter until the day comes when you question whether the lower oil pressure you see on the gauge, after a good long 20 mile 70mph plus run, is good enough for the engine. I decided it wasn't and fitted an oil cooler. As expected, the oil temperature in the oil tank went down and the oil pressure went up. Relative to the graph, my oil temperature along the bottom axis is now further to the left and the oil viscosity further away from the 'too thin' area and avoiding the drop towards the 'too thin' area. With the 20W50 oil (with a return filter) this should also give me better oil flow at start up from cold and reduce the multigrade deterioration over time due to the lower oil temperature.
Concerning additives - As the ambient temperature dropped with winter approaching last year I noticed that at start up from cold I needed to raise the tick over screw a little to get a reliable tick over for a few minutes until warm which it didn't need previously. I added some ZX1 Extralube to the oil tank as an experiment and found that the cold tick over increased and I didn't need to alter the screw. After the winter lay up I'm interested to see if this is still the case.   
Title: Re: Filter in Oil Feed Line
Post by: bsa-bill on 21.01. 2011 11:20
Hi Alan
I tried the ZX1 Extralube in my project as it had a sometimes sticky valve, Have to say I was impressed I did however drain it out after a hundred miles or so thinking it might prevent proper bedding in ( not sure I was right but better safe than sorry),
Now to get back on subject (almost)  thinking about low oil pressure, back in the day most cars had oil lights that came on to warn you of low oil pressure, these (IFIRC) came on at 5LBs  !!!
Title: Re: Filter in Oil Feed Line
Post by: lawnmowerman on 21.01. 2011 12:28
Hi Bill

What symptoms did you get from your sticky valve - was it similar to mine in my "Spitback through carb and backfire" topic?
I suspect a sticky valve after the winter layup and was thinking of trying the ZX1 Extralube - where did you buy it?
Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 21.01. 2011 14:03
Thanks Lads.  This ZX1 stuff sounds very promising.  Would be interesting to see Alanp's final judgement after startup this year (I think I will change my name to Alan(N) to avoid confusion).  I am very envious of your oil pressure gauge.  Very useful instrument (much more so than the 'too-late' warning light).
Title: Re: Filter in Oil Feed Line
Post by: alanp on 21.01. 2011 16:29
I suspect a sticky valve after the winter layup and was thinking of trying the ZX1 Extralube - where did you buy it?
Title: Re: Filter in Oil Feed Line
Post by: lawnmowerman on 21.01. 2011 16:56
Thanks Alan
Title: Re: Filter in Oil Feed Line
Post by: bsa-bill on 21.01. 2011 18:53
As Alan says Jim Halfords.
and the valve sticking - It was when setting the tappets, the timing side Ex valve seemed to momentarily stick and then came up and make a "click" presumable when taking up the play between pushrod and tappet/cam or cam follower.
Upon investigation I discovered this happened as the crank came round to the point where it was rubbing on one of the long studs for the primary chaincase, This what I put it down to but after reading the Rockerbox article I wonder if I've missed something.
So the plan now is to have a very close look at the valve springs in situ and if it looks like they are binding anywhere I'll lift the box off and engage a Dremmel type thing.

On the subject of Dremmel I see the smaller one is on offer locally (300 is it) - is this one worth buying or is it better buy to go for the larger (4000 I think )
opinions welcome ( sorry Jim getting off subject again)
Title: Re: Filter in Oil Feed Line
Post by: nigeldtr on 21.01. 2011 20:39
Alan @Ncl,

Super explanation and graphic.

Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 23.01. 2011 20:31
Having now benefited from all of your posts, I have finally decided to 'do the conventional thing' and move my oil filter from the inlet side into the return.  Have managed to do this without cutting into the other armoured hose and have also retained the same filter location; underneath. mounted on a bracket off the centre stand stop.  It is retained quite rigidly by by a big circlip (see pics). The filter is a C103 with 3/4 UNF thread and surprisingly, is still readily available at Halfords. Its bigger than the Norton ones bur presumably offers minimal flow resistance.

Took the oil-tank off and gave it a good clean out.  It was absolutely filthy (shame on me) despite having had a paper filter all these years. At least with my previous set-up the engine was protected from anything getting past the oil-tank suction strainer, due to the position of the filter (I am still a bit nervous about removing this backup).  It will be interesting to see if the repositioning reduces such accumulations in future by trapping all this crud somewhere that it is more easily removed (i.e. in the return filter).

I have also decided to stick with the expensive Silkolene 40 monograde that I bought, partly because its paid for (the scrooge in me) and partly because it 'looks and feels nice'.  Not the most compelling justifications I grant you but since there was no clear majority for switching, this was the path of least resistance. At least this stuff is true grade 40 rather than basically a 20W with additives to reduce its propensity for viscosity reduction at higher temperature (thanks, by the way, to Nigel for your kind comments on my previous post).

The moment of truth draws closer but before firing up, I may have one more new thread to launch.
Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 27.01. 2011 11:20
All seems to be quiet on this front lately (only me posting so hope I am not overstaying my welcome).  I thought it might be worth trying to pull together all of the various contributions made on this topic in the form of a table (see attached).  This comprehensively lists, I think, all the various factors raised for consideration by your various posts.  It then lays out alongside each one, features of Multigrades and Monogrades for comparison.  No real conclusion defining which is ultimately best of course but depending on your primary concern, may provide a useful summary of the arguments for and against, all on one page. 

I had an email exchange (see footnote below) then a chat with the Castrol Classics tech guy who was extremely helpful.  He kindly read my table over and offered a few comments but did not take exception to anything that is included here.  He did point out that while monos do contain some detergent, its very minimal compared to multis. 

I hope this table may prove useful, especially to newcomers wanting a quick intro to the debate.

Initial Email Reply from Castrol:
The current Castrol recommendation is Castrol Classic XXL40, however as you have the in-line filter then you will probably benefit from the Classic XL20w/50. The one thing to take into account is that with roller mains the chewing action of the rollers on the multi-grade will reduce it's viscosity over time, so change the oil every 1000 miles and you will be fine. Monogrades (XXL40) are not affected in this way and retain their viscosity even when due for change.
Title: Re: Filter in Oil Feed Line
Post by: lawnmowerman on 27.01. 2011 12:06
Thaks Alan - really useful summary. I have just changed the oil and used some GTX 20/50 that has been in the garage for a few years. As others have said, the main thing is to change it regularly rather than be too worried about the maufacturer. Personally, with a rebuilt engine I will stick with 20/50 but a filter and OPG is on the "to do" list.

Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 27.01. 2011 13:44
Thanks Jim.  Sounds sensible.  I attach a pic of my filter as now refitted on the return side, underneath in the airstream (sort of).

In passing, I tried a crude test watching the run down from the tank under gravity though the flexihose, with and without the filter in the engine feed line (before changing over).  This was with the fresh Mono40 grade (very thick at current Newcastle temperatures).  Did not look much different with and without the filter. Concluded the filter did not pose an obvious increased resistance to flow under these conditions (a pathetic dribble in both cases) but this was hardly a solid 'scientific experiment'.

Title: Re: Filter in Oil Feed Line
Post by: orabanda on 27.01. 2011 15:09
Just a note about (any) oil; shelf life is around two years. After that degradation of the additives due just to aging means that it no longer performs as when originally mixed.

Use your oil within two years of manufacture date, before its properties permanently change.

My research (after the same soul searching that everyone else has gone through) is that Penrite Enduro (check out the product on their website) is the best choice of multigrade for my A10's (and XT500). Note the high zinc content, which helps reduce wear at high load contact surfaces such as cam lobes and followers.

Some multigrades have significantly less zinc content.

I use return filters of my own design in all the A10's.


Title: Re: Filter in Oil Feed Line
Post by: A10Boy on 27.01. 2011 17:07
I used to have a Hardly... Sorry...  *red*

The oil for that was made by Penrite according to the dealer, it was a 20-50 with high zinc content. So for UK users if we want Penrite 20-50 you can buy it from a Hardly dealer.

Title: Re: Filter in Oil Feed Line
Post by: lawnmowerman on 27.01. 2011 17:12
Hi Richard

I did not realise that oil had a shelf life. My logic was that it had been in the ground for about 25 million years so another 25 years in the garage should not make all that much difference - forgot about the additives  *doh*
Live and learn

Title: Re: Filter in Oil Feed Line
Post by: muskrat on 27.01. 2011 19:02
Nice work Alan, very informative.
                                             I'm still a multi/filter/additive type of guy. I agree that multi's don't last as long, I see my oil pressure starting to drop after about 500 miles. I change it at 1000 to 1500 miles so not really a problem.
 One thing that is confusing is that modern machine manufactures recommend multi, but their oil runs in the gearbox and clutch. Can't get any more chewy than that.
 And what about synthetics ?
Title: Re: Filter in Oil Feed Line
Post by: Alan @Ncl on 27.01. 2011 19:56
Thanks Muskrat
Yours is a good point about the 'chewing' in gearboxes etc. and sadly, I can't clarify further  That point about longevity was added onto my original list following my communication with Castrol and I just took it at face value. I know that old BL cars like minis and maxis also had common engine and gearbox but can't recall whether they had to have more frequent oil changes. Richard's point about shelf life is certainly noteworthy too.

The link between cold running and sludging was also added based on the Castrol man's comments.

Title: Re: Filter in Oil Feed Line
Post by: alanp on 14.02. 2011 14:55
Further to my post on 20th Jan about the wet sumping you get with 20W-50 oil, I have a more accurate measure now based on a drain of the sump I have just done and the precise number of days it has stood. The daily quantity of oil draining into the sump has been 36ccs.
This is with a new SRM pump and backs up the fact that 20W oils are quite thin at the sort of temps we have had over the last month or so and can be expected to drain past the pump easier than SAE 50 grades. I find this daily 'sumping' value quite eye opening. I don't have a value for SAE 50 grades on this engine for a precise comparison but will bet it's a lot less.
Keep this in mind for when you get the bike ready for the riding season after a long winter lay up. Just drain what's in the sump and put it back in the oil tank.
When I ran a DBD34 500 Gold Star a couple of years back it was a pig to start after each winter lay up and when it eventually decided to start it used to set the smoke alarms off in my garage - I now know why, the oil build up in the sump was dragging like mad on the crankshaft and oil was working it's way past the piston skirts until the scavenge side of the pump eventually got the oil in the crankcase under control.
It would be good to get some figures for 40 and 50 grade oils from others who know the number of lay up days and can measure the quantity drained from the sump.
The sun is shining and my Ducati 999S has been out stretching its legs and growling in delight (or was that me?) and if it keeps this up the BSA will be out soon as well since it seems the road salt has virtually disappeared down in SW Devon.