View Full Version : Rotary oil pump

01-24-2010, 7:25 PM
Just wanted to take a poll on Rotary oil pumps for Triumph unit 650s .. I know they are better but are they really the end all of oil pumps in a Triumph? ...

Looks like with the hunt mag, a Rotary pump ...I'm going to have to drop over a grand or better ...Looks like my search for a good deal on a used mag is useless ...

I might let the oil pump idea go and just grab a new hunt and let it be ....I just don't like the pressure I see coming back into the oil tank ...comes out the return in spurts the return picks up when you increase the rpms but seems to carry air in the line when idle.. I do get good pressure a the rocker feed though...

01-24-2010, 7:32 PM
The function of the rocker feed is to lubricate the rockers not bathe them in oil. As for the spurts of oil you are seeing in the return, that's totally normal. The stock pump only pushes oil when the intake cam moves the plunger in the oil pump down which causes the intermittent pulses. Therefore, as you increase the rpms the oil spurts will increase.

The rotary pump on the other hand is gear driven and the oil flow is continuous. Rotary pumps are great but expensive (as you've noticed). Unless you're racing the motor or extremely OCD you don't really need a rotary pump. Keep in mind people have put thousands of miles on Triumphs with standard pumps without needing anything more advanced.

A less expensive alternative to the Morgo rotary pump is to run a Morgo high output oil pump. It looks like the stock pump but the plungers are much larger. You can also replace your 650cc stock oil pump which uses a two valve system to the 750 oil pump which is a four valve pump. It is a straight bolt in and no modifications are needed.

01-24-2010, 7:44 PM
If you are concerned about volume, you can fit a later (1976, I think) stock pump.

01-24-2010, 7:51 PM
THANKS guys! that was what I was looking for ....I can be alittle OCD on things for sure LOL ...I am a worse case scenario type person ...... I like things to be damn near bullet proof ... I was unaware about the difference in 650 to 750 pumps that is a new one ....Cool

The rocker feed is not bathing oil but it does have lets say a more "constant" stream ....I had someone question the ariel oil tank ...Which I can't see any difference in over a Triumph one....

01-24-2010, 7:58 PM
I'd only be concerned if you were having the oposite problem and there was very little oil getting to the rocker boxes. Some race bike bulders would run their rocker feed straight from the timing cover to force even more oil up top. This is totally unnecessary on the street (not to put ideas in your head - and seeing as how that's not an issue with your motor forget I even mentioned it) I'm just using that to calm any worries you might have with your oil system.

01-24-2010, 8:03 PM
You can not put a unit oil pump on a pre unit . They ran the holes the opposite way . So if this is for that pre unit you keep talking about then don't run the later oil pump .

01-24-2010, 9:16 PM
You can not put a unit oil pump on a pre unit . They ran the holes the opposite way . So if this is for that pre unit you keep talking about then don't run the later oil pump .

No this is something I'd like to do on my 70 TR6R I got done last year ...Just some improvements I see in the near future .... I have acquired a few bikes this last year I know it gets confusing ...Hell I can't keep track sometimes LOL... Good looking out appreciate it ...

01-25-2010, 12:39 AM
Rotary oil pumps can fail as were stock pumps don't have enough parts to really fail. They either work or they don't. One of the guys that helps out at the shop owned a flat track team from 69' to 89' and never ran a rotary pump. His personal bike dynoed at 72 h.p. to the rear wheel!!! and had the stock pump. The engine was FAR from stock (Norton 850 crank, 530 lift cams, 11 to 1 compression, custom machined intake ports right over the valves, with huge Delorto carbs) but he ran the stock pump because it was reliable. Just some food for thought. And it sounds like your stock pump is working perfect, Greaser Mike already explained how the stock pump works. Good luck with your bike though.