OIF A65

[EDDIE SIMPSON]

Hello all,
i ve acquired a neglected 71 OIF A65 and have stripped it down to check the old spine weld repair and change the swing arm bearings.
However my question is whether its a good idea to cut off the oil feed pipe and block this off. Then fit an aftermarket cartridge filter with the oil feed from the base. Has anyone done this mod and out of interest,how did you block off the feed pipe ?

[limeyrob]

Are you sure the SA bushes need replacing?  They last forever and its a pig of a job.
Yes I fitted a cartridge filter to the return oil, there's space to a Norton Commando style filter under the SA.  It has to go in the return as this is pumped, the feed is suction and the pump may not prime.

[Peter A]

Hi Eddie,
I've just fitted a Norton external filter to my 71 A65FS. It needs connecting to the return oil pipe. Note that the Norton connections are for a 3/8 oil pipe whereas yours will be 5/16. It will fit but is tight, I warmed the pipe first with a hot air gun to soften it slightly. The filter will fit nicely beneath the right hand side panel, you will need to make a bracket and I fixed it via the bolt that fastens the rear fender to the frame.I'll try to post some pics.
Pete

[EDDIE SIMPSON]

hi Peter and Rob,
i also have a pre OIF a65 with an external filter in the return. But i do think there are advantages in having the filter in the supply side and not so easy to find a place to mount an external filter on the OIFrame.The B50 had a supply paper filter i read, but this conversion is the first i ve heard of it.
Maybe the bushes were not too worn but the bobbins were corroded as hell. i ve added a removeable i/4" bolt in the centre section for greases and oil as pin removal was challenging.
I m well pleased with the project as its not used since 1984  and the engine looks untouched inside. The only bit i dont like is the weld repair to the bottom spine  lhs bracket which i will leak test.

[limeyrob]

The problem with a feed side filter is is gravity fed, on cars the feed side filter is always after the pump so I think it has to go in the return.  Its many years since I fitted the filter to my A65 but I'm sure it went low behind the frame spine.  I also has a electronic ignition amp to hide.
I had mine form new and the sludge trap blocked at about 20,000 miles and seized the bottom end.  I got it rebuilt at Small Heath a few months before it closed.  I fitted the filter after that so my advice is strip the bottom end and check the sludge trap so you start with that clean when you fit the filter.
I tuned my engine up quite a bit and used to rev it hard, this lead to a few frame cracks and that's one reason I sold it, there were a number of welds and I was sure there were going to be more cracks in future.

[EDDIE SIMPSON]

yes to sludge trap and yes to bottom frame spline being too weak.
the frame spine is not the easiest to repair or upgrade.

[DMadigan]

I make a mount and filter can for the HiFlo 116 filter (used on the H*nda CR450) for the OIF:

Pipes are made to suit:

This is on a triple OIF:

I also made OIF base plates with the filter can integrated:

[limeyrob]

That's very nice!

[Superflash]

+1 on a very nice bit of kit. Makes my u-bolt and bit of angle iron look a bit ordinary...😎

[EDDIE SIMPSON]

with a cartridge filter used in the OIF return flow pipe can you still use the original 3 way oil / engine connection or would you have to the rocker feed pipe and make a tee off after the filter?

[limeyrob]

Its a long time ago but I don't recall doing anything other than fitting the two connections to the filter and making a bracket.  I left the rocker oil feed alone. It worked fine.

[DMadigan]

With the 3way junction at the motor and the return line filter it will send more oil to the top end.

[EDDIE SIMPSON]

hi Dave,
if that is the case . more oil inside the engine. maybe a small oil cooler would be beneficial for those motorway journeys ?

[limeyrob]

I used to run mine hard and it got its oil very hot on long runs.  I ended up only using straight oils, usually straight 50 in summer and 40 in winter.  Had I not sold it I would have fitted an oil cooler. 

[EDDIE SIMPSON]

at the end of bsa, they recommended 20/50 for the OIF. Our bikes do run hotter nowadays and i want to throttle this A65 , so will fit a small cooler and see how it goes.