Board index Flathead Power-Technical Questions, Answers, and Suggestions Big Twin Flatties Flathead.......power?


Post Wed May 12, 2010 7:40 am

Posts: 575
Location: devon,england
hi guys wrote to the ,oil pump people vt-cycle as follows
On Wed, 12 May 2010 09:12:54 +0100,

<> wrote:

> hi, my names jib im from england ,and am a member of the flathead power

> tech forum, your website was recently posted as a link ,in one of the

> discussions . are your flathead oil pumps availiable please and if so


> much are they please, also do you have any specifications, such as flow

> rates, hot/cold oil ,etc. i look forward to your reply,thank you regards

> jib
and they replied as follows, hope this helps regards jib

Hello jib,

thanks for your interest, here is some info about the feed pump.

New oil feed pump features evolution sportster gerotor gears, aluminium


It is bolt-on for harley WL, UL, G flatheads.

flows 1 liter in 45 seconds free flow.

Oil pressure is set to 25-30 psi , when operating temp idle pressure is

about 10 psi, depending on oil hole size and timing in pinion


So, this will handle skirt oilers if you use them.

HD flatheads really need more oil to cylinders and pistons.

I recomended modern 3-piece oil rings with this pump.

in comparison,

The OEM scavender pump flows 1 liter in 30 seconds.

Ofcourse, this is not a cheap product.

price was supplied, removed to comply with boards no price policy.

Best regards,




Pettistentie 280

21420 LIETO


Last edited by jib on Wed May 12, 2010 1:08 pm, edited 1 time in total.
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years

Post Wed May 12, 2010 10:16 am

Last edited by panic on Sun May 16, 2010 10:26 am, edited 2 times in total.

Post Wed May 12, 2010 12:08 pm

Posts: 93
Location: Norway
panic wrote:
Looks very nice.
Gerotor is the preferred method: least power used, smallest pressure cycles, high output at low RPM.
However: 1 liter in 45 seconds (= 80 l/m). Stock return pump is 1 liter in 30 seconds (=120 l/m).
How is this not going to overload the return system?

Panic....1 liter in 45 sec equals 1.33 l/min and 1 liter in 30 sec equals 2 l/min. do we know the rpms when this is tested?

Post Wed May 12, 2010 12:40 pm

Last edited by panic on Sun May 16, 2010 10:26 am, edited 1 time in total.

Post Wed May 12, 2010 12:59 pm

Posts: 349
Location: Champaign-Urbana, IL
OK ... If that oil pump costs 670 Euros, that's $846 ... Even if you take away the 22% VAT for American buyers, that's $693 plus shipping!!! Doesn't that seem just a tad expensive to anyone out there!?


Post Wed May 12, 2010 2:17 pm

Posts: 83
I tried to buy a pair of their UL cylinder heads. Combustion chamber look like the KR heads. I asked Vesku about the compression ratio for the heads and he told me they are 6.5:1 for 74" engines and 6.9:1 for 80" engines. He also told me they flow better than OEM heads due the shape of the chamber. He was very nice, answering promptly all my questions, but unfortunately I couldn't buy the heads because the only payment option is bank tranfer to a bank account in finland. No paypal, no credit card, no international money orders. My bank manager doesn't know ho to do the tranfer, so I gave up. I think Vesku sells mostly to European buyers living in the euro zone...

Post Wed May 12, 2010 2:46 pm

Posts: 219
Location: Georgia
I know the original thread is long gone but;

I did a quick look on J&P for their price for a replica stock oil pump. $434.99. It is probably from Ted's. If so it is not worth anything unless you are never going to crank the engine or pour oil in it. I forget what I paid for the Ted's pump on mine but if it was more than $50.00 it was overpriced. I know there are cheaper and better stock pumps available but they still flow like a stock pump. I for 1 am interested in this pump.

Post Wed May 12, 2010 2:48 pm

Posts: 51
@ helsingborg .
Bank credit transfer is the easiest thing of the world (for us European). With my on-line banking done at one minute from my Pc. I cannot understand why you have to involve a second bank ( like paypal ) to do make the transferfor you :?: It is illogical to me and complicated.

Post Wed May 12, 2010 4:17 pm

Last edited by panic on Sun May 16, 2010 10:27 am, edited 1 time in total.

Post Wed May 12, 2010 4:41 pm

Last edited by panic on Sun May 16, 2010 10:28 am, edited 1 time in total.

Post Thu May 13, 2010 5:02 am

Posts: 1676
Location: Interlaken, NY USA

Just thought I'd present a few numbers so people can make apples to apples comparisons:
Woody determined that the stock return pump freeflows .55gal/min @ 2400 engine rpm, roughly equals 2.08L/min.
From this I'd say the Finlanders' are taking their flow readings at roughly 2400rpm's.
Stock pumped 1L per 12 minutes @ 2000rpm
72 up sporty, 1 L per min. @2000rpm
Jim's modification, somewhere between the last two figures.
Panic makes a good point in that we don't really know if more oil is an answer to the BTSV's problems. I mean, I think it is, when used as a cooling agent. However, mine's still a work in progress, and who knows if I'm doing it to the right places, although I hope I am :roll:
However, Paul Freibus does piston oilers al la Twinkies, apparently uses the H-D parts. He makes great efforts to get maximum oil to the bottom of the pistons and the big end, also doing full flow pinion, 3 hole crank, and adds a seal at the pinion, among other things, to keep pressure up so the piston oilers will work.
He also does the K style combustion chamber, but it is not an exact copy. His empirical testing shows the BT needs a somewhat different angle and position than the K. He also made a revealing statement, "Flow benches Lie!", last year in a discussion we had at Rhinebeck.
As Panic said, it took the masters a long time of trial and error to come up with the combustion chamber shape that worked.
But Paul's work really just proves what works on a Bonneville Run, not necessarily what a street bike needs.
I'm certainly not dissing the gerotor pump, It looks great and is a good off the shelf solution. If money was no object, I'd take the easy way out myself. Well, I probably would. We all know I like to screw around way too much to always take the easy way out!
On the heads, I'd probably pass, but only because he copied the cast iron head profile to make his aluminum heads with shelf chamber. Personally, I like the external looks of the H-D aluminum heads better. Just my personal tastes there.
As a side note to those who take interest in these things, I'm quite convinced that bypass oil from the pump is not needed in the cam chest. That is, IF you're using a larger than stock pump. All oil that goes to the flywheel chamber eventually ends up in the cam chest, and is thoroughly distributed throughout the chest as it blasts in on the breather air. Remember the Sporty cam chest has no bypass oil flow to its cam chest, to no ill effect.

Post Thu May 13, 2010 8:04 am

Posts: 1654
from experience of tuning and racing vintage British engines, I would say that maximising oil flow to the big end and ( to a lesser extent ) the main bearings, is the single most important thing you can do.

Most British engines have the barrel spigoted into the crank-case. A detail sometimes seen, is to shave the end of this spigot to provide a protrusion, maybe 2-3mm, of the piston skirt into the crankcase to pick up oil spray. Seems to work; at any rate skirt oilers really aren't a live topic in vintage racing circles over here. Of course, we don't race sidevalves to any great extent, and most vintage racers use methanol, so the temperature issues may be different.
Shoot, a man could have a good weekend in Dallas with all that stuff...

Post Thu May 13, 2010 8:10 am

Last edited by panic on Sun May 16, 2010 10:28 am, edited 1 time in total.

Post Thu May 13, 2010 9:30 am

Posts: 767
Location: CA USA
Interesting discussion. Panic I think you've hit on something with the head steady thought. HD decided that the K needed 4 points of contact at the head bolt interface which moves the right side contact point further right. This along with the piston oilers seems to have solved the problem for the most part. I've often thought of making a K type head steady for the WR to see if it would help with motor mount breakage.


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