Oil retaining ball modification (to A65 system)

[Topdad]

Hi Kiwi, thats a yes ,look at orabanda's reply to my earlier  incorrect post above , regards Bob

[bsa-bill]

Just for the sake of variation, instead of making a liner for the hole you could install the tube inside the spring so as to limit the travel of the ball but leaving enough space for the pumped oil to get past.
My twopence worth would be one of two ways.
1 - similar A65/50, drill out just big enough to remove existing ball and spring, then drill out larger from pump to just short of oil feed to bearing, (larger being large enough for ball and flowing oil), then drill for smaller holes at the periphery of the bottom of the larger hole so that the ball could not block oil flow, counter sink the pump to accept the ball.

2 - fit the  Bri-Tie non return valve that I have lying in a box in the shed as neither bike wet-sump to any extent after rebuilds, not popular with everyone but worked for me just fine and has the same components as your about to retro fit

PS I'm not good with apple carts

[KiwiGF]

Im not sure of its effect on the design but the std a65 pump has a bigger supply hole to suit it's revised spring/ball arrangement?

[wardleybob]

Hy guys you drill a 5/16 hole from the front .tease out the original ball and spring.I put a 6mm ball in and a stronger spring.
The ballseats against the oil pump. I counter boar the back of the pump slightly.  All done without spliting the cases
Make sure you get all the crude out. Ps it will still wet sump if the pump is worn. I put a sump plug in and if I am not useing
The bike I let it drain out.

[kiwipom]

hi guys, wardleybob says(Ps it will still wet sump if the pump is worn) so a worn pump will let oil track from the cogs that supply pressure, to the return oriface and back into the return pickup,is this correct?cheers

[chaterlea25]

Hi All
Kiwi, the worn pump will let oil leak out along the drive spindles, out between the end plate and casing and some will leak straight through the porus alloy 

Bill, the difference between the britie and standard or A65 is that the oil is sucked through the britie valve and pumped through the standard valve

If the pump body is counter sunk or the ball tapped into the alloy body the pressure the spring exerts is lessened as the seating area becomes wider !!!!
Just rotate the ball against the pump body till you see a continuous shiny line, that will be enough !
Beware of gasket fibres near the seating or spring as these will prevent the ball from seating

HTH
John

[kiwipom]

hi guys/chaterlea, it must be quite tricky making sure that the ball stays in place while fitting the pump,also i read somewhere that the A10 pump was not designed to `create a vacuum`so a valve on the oil feed would presumably lessen it`s capability,cheers

[bsa-bill]

Bill, the difference between the britie and standard or A65 is that the oil is sucked through the britie valve and pumped through the standard valve

Yep that's all true John, but I don't altogether go with the pump is not designed to suck theory, fair enough it's a gear pump as opposed to a type with pistons which might shift air more efficiently, however the return side of the pump is just a slightly larger version of the feed side and the return side is constantly sucking and sucking a mixture of oil and air and also having to suck open a ball valve, the feed side has an advantage in that there is a weight of oil ready to be sucked in in normal circumstance. 
I imagine the fear is the pump wont prime, but again the return side manages to do this in circumstance where it constantly loses oil and has to pump air

[kiwipom]

hi guys,some pics of A10(on left) and A65(on right) oil pumps. virtually the same apart from rotation in opposite directions hence A65 drives from the upper cogs and A10 from lower. O-ring on A65 to stop oil flowing through to the drive cog which could be applied to A10 after a bit of modification, i dont see any advantage in the A65 apart from that. Cant see much of a chamfer for ball-spring oil control, cheers

[kiwipom]

hi guys,just seen that the last pic is A65 on left and A10 on right,cheers

[bsa-bill]

Hi kiwipom - I have an A65 pump that I thought I might use but noted that it is a tad longer than an A10 one so it still lives in the shed.
do you know if it is possible to swap the drive end and shaft between the two pumps, I didn't try with mine as I thought I'd mark the cogs before dismantling (pangs of conscience since I did not do this with either of my other bikes pumps)

[kiwipom]

hi bill,no i have tried switching top and bottom set of cogs on the A65 pump which you would have to do to get the drive in the lower position which would then pump in the correct direction as you have to switch the rotation, but was not possible due to too tight/slight difference in cog housings, there does not seem to be any point in pursuing the exercise as the pumps are almost identical apart from the small o-ring which could be made to fit on the A10 pump,cheers

[bsa-bill]

Cheers for that Kiwipom
Looks like I'm going to have to resurrect my sellers account, to much stuff lying around doing nothing but taking up space

[KiwiGF]

Bsa bill, i have an a65 pump body with a10 drive shaft casting/shaft, works fine, gears are wider than a10 so more flow, my bike does not wet sump even though i do not recall seeing an o ring inside it.

It took a bit of filing of the holes in the drive end casting to get it to spin freely.

So dont sell your a65 pumps!