SRM oil pump

[ellis]

I know SRM don't advise fitting their pump to a bike with a spin on canister filter. Has any body done this and if so what were the results. Or should I not fit such a high capacity pump with a car type filter. 

ELLIS

[Dean]

I was not aware of SRM's recommendation and have fitted their pump and a spin on filter. I wonder of that accounts for the recent onset of wet sumping? I not sure why though?

[Triton Thrasher]

Their logic may be that once you stray from standard spec, they don't know what they're guaranteeing.

[RichardL]

As far as I can see, SRM has not included such a warning in the description for the pump in their online shop. You would think that is where the warning would need to be, rather than selling the pump to the unsuspecting filter user. I also have an SRM pump with a spin-on filter and have gone about 1000 miles that way with no apparent trouble and very little wet-sumping. (Just finished a bunch of yard work in 100 deg. F., so too lazy/tired to go looking for the pump install instructions.)

Richard L.

[a101960]

It seems to me that SRM have some rather bizarre ideas. For example if SRM rebuild an engine for you, the warranty is null and void if you fit a filter of any description. Similarly the same thing applies if you use anything other than straight oil.  Whats that all about? Personally  I fail to see the logic especially in light of the fact that oil has advanced so much since the days when BSA were still extent. In fact in the later years BSA were in fact actually specifying multi grade engine oil. In the Haynes A10 manual (first published 1973) it says in the acknowledgements  section “Our thanks are due to BSA Motorcycles Limited for their assistance” and then goes on to recommend Castrol GTX 20/50. If you by an SRM sump drain kit they supply Allen bolts rather than studs. SRM have a good reputation, but I do not think that they are always right.

John

[metalflake11]

S.R.M. Do not recommend fitting an additional oil filter, period. The bike should also be run on straight oil and not multigrade, the engine was designed that way.

Like it or lump it, those are the facts, and I am staggered that people with all the evidence before them choose to ignore them. There is a reason they guarantee their work if you follow their advice, but not doing so invalidates said guarantee.

[metalflake11]

It seems to me that SRM have some rather bizarre ideas. For example if SRM rebuild an engine for you, the warranty is null and void if you fit a filter of any description. Similarly the same thing applies if you use anything other than straight oil.  Whats that all about? Personally  I fail to see the logic especially in light of the fact that oil has advanced so much since the days when BSA were still extent. In fact in the later years BSA were in fact actually specifying multi grade engine oil. In the Haynes A10 manual (first published 1973) it says in the acknowledgements  section “Our thanks are due to BSA Motorcycles Limited for their assistance” and then goes on to recommend Castrol GTX 20/50. If you by an SRM sump drain kit they supply Allen bolts rather than studs. SRM have a good reputation, but I do not think that they are always right.

John

Bizarre ideas?........I prefer to call it feedback from building many thousands of engines that have covered millions of miles. Oils may have moved on to keep up with modern engine engineering, an A10 is an old design of engine.

Castrol were back handing anybody and everybody back then to endorse their products, and Haynes are notorious for their mis-information in their manuals anyway.

Straight oils are designed to let go of foreign bodies, multigrades are designed to hold them until they are filtered. Straight oil leaves these foreign bodies in the sludge trap before any damage can be done by them. Multigrade will try to hold on to them, and carry them all the way to the filter which can only be fitted on the return side. That means all the damage is done before it is filtered.

It really is that simple.

[RichardL]

Well, there are a lot of twists to this that threaten to bring on another full-blown oil debate. I'm no oil expert, but I do have a few comments.

As I understand it, oil in the days when our bikes were made did not have limits on the amount of zinc included. Therefore (again as I understand it), flat tappets were well protected against wear. Today, zinc is restricted, so I use Valvoline VR1 Racing Oil, which has about as much zinc of any oil I can buy at the local auto parts store.

As has been recently explained here (so, yet again, "as I understand it"), it is the detergent in motor oil that suspends particles for filtering and not the elements that control viscosity behavior through various ambient temperatures as seen in multi-grade oils.

Finally, if BSA was so concerned about using straight (single-grade) oils, how would that explain what is seen stamped into the top of the oil can in the attached pictures?  (That can is a prized possession.)

I am happy to be corrected if wrong but, then, I am going to ask those who are oil gurus to get on the same page with their stories so that us oil novitiates will not be confused.

Richard L.

Adding a close-up (with my daughter accidentally-on-purpose in the background).

[a101960]

Finally, if BSA was so concerned about using straight (single-grade) oils, how would that explain what is seen stamped into the top of the oil can in the attached pictures?  (That can is a prized possession.)

Richard, exactly! Metalflake11, you might find this to be an interesting read  http://www.realclassic.co.uk/techfiles/oil030319.html  Well actually so might everyone else.
John

[duTch]

 Thanks Richard, I was thinking same, but you put it better than I would've

      Well, there are a lot of twists to this that threaten to bring on another full-blown oil debate. I'm no oil expert, but I do have a few comments.    .........

.....>....  I am happy to be corrected if wrong but, then, I am going to ask those who are oil gurus to get on the same page with their stories so that us oil novitiates will not be confused.

Richard L.
...........   

[bsa-bill]

S.R.M. Do not recommend fitting an additional oil filter, period. The bike should also be run on straight oil and not multigrade, the engine was designed that way.

just in an argumentative mood so I would strongly advise against the use of any crank end oil feed, the engine was not designed that way

[KiwiGF]

On the sludge trap.....does anyone know for certain it was designed to store small metal particles? Anyone actually forensically examined the sludge?  I thought that (maybe) it was supposed to store the larger particles that could not fit through the big end clearance, that clearance being less than 001 on a good engine.....it seems to me that whatever oil you use those larger particles will have to stay in the sludge trap, until the big ends get sloppy anyway 

I run cheapo castrol 20/50 and a "commando" filter on a rebuilt engine, oil changed every 1000 miles ish, filter every other oil change, no problems so far but I've not done 10's of thousands of miles.

[polly]

I hated the old american qt cans .....if your spout was not sharp or you didn't whack it in hard enough the first time the can collapsed  and the oil went every where

[muskrat]

So SRM are a bit hypocritical with all the mods (roller timing side conversion etc) they sell, and yet insist on mono oil and no filter!
Cheers

[mikeb]

in reply to the original question, i have fitted an srm oil pump and a spin on filter (in the return line). but only done 1000 miles since doing so. the return flow (into the tank) is better than the old original pump, and no wet sumping (i replaced the ball/spring valve in the crankcase too).
i have noticed that if the bike is sitting for a week there's a bit of overhead noise that takes a minute to so to settle down, and I've wondering if this could be due to the increased time it takes for oil to reach there with the longer return path through the filter.