750 head oil flow

B

Basketcase

Senior member
How does the oil "well up" in the channels in the top of the 750 head and actually reach the cam lobes ?

It seems to me that with the engine tilted forward the oil will just spill over at the front and miss raining on all the important stuff.
 
Hi BC - The oil pump has (should have) the power to  allow enough oil to go to the controlled orifices to lube big ends - then still push the rest up the barrel & head to feed along the rocker spindles and lube the cams. There is also splash from the camchain to lube the centre bearings. Later models had small holes drilled from the top oil gallery to squirt oil onto the camshaft itself.
  The std oil pump is questionable as to whether it supplies enough oil at low RPm - but, as most seem to run for years OK, perhaps this is not such a problem. The SFC uses un uprated 9mm cog setup pump and 10mm ones are available - Regards - Phil
 
Hi, BC.
From SF2 on the 750s had additional oil holes in the head, see the pics.
Easy to modify older heads, once the engine is apart anyway.

hth
Ernesto
 

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Thanks for the photos Ernesto.

I presume the hole is drilled behind the centreline to allow for the angle of the cylinders.

Cheers,

Rob
 
You're not looking at more then 3 PSI to the top end, providing the Top End is clean an true to specs for lubrication an cooling but oil flow volume is critical.

If you tap into the main casing oil gallery across the bottom end of the jugs to read  pressure  you don't want to read more then 3 PSI or a build up in pressure will indicate you have a problems in the top end.

3673644033_668a1ab38b_o.jpg

You see that Brass plug Bolt Bolt with at string of Oil leaking over the case - It wasn't leaking as I just finished a PSI Check Oil Flow to the Top End. 3 PSI Perfect. Anything more or less and you're probably looking at issues on the top end. Don't forget that the Mains feed off this Gallery and report Nothing as they are Gallery feed with no back pressure. Oil pressure readings will not determine if your bottom end has Exploded. Less the failure of the Oil Pump, Main Bearings, Rings and Piston Ware are affected primarily due to leaking g Main Seals, Lean Carbs and Bad Timing.

You can Double Tap this Gallery with a plug between them to mount a Oil Cooler but not necessary with any Breganzie 750.
 
no need for an oil cooler unless your racing, sorry chaps I may open up a can of worms here but I must say, Ron, they are the most exquisite headers I have seen, visually, for a sf, ever....
 
Ernesto said:
Hi, BC.
From SF2 on the 750s had additional oil holes in the head, see the pics.
Easy to modify older heads, once the engine is apart anyway.

hth
Ernesto
Click to expand...
I drilled these holes in my SF1 head assuming they MUST be an improvement - but later blocked them back up. My original cams and rockers had done well over 160,000km and had minimal signs of bad lubrication - I changed them when I went to a 5C cam and the later lighter rockers.

I actually think the addition of the holes can reduce the flow through the spindles to the cams and rocker faces, due to the relatively low volume pump. Have done probably another 50,000km on the new setup (no holes) and everything has been hunky dory up there. Lots of very hard riding, ride days, race days.

The biggest killer of SF top ends is the middle front cylinder studs blocking the flow to the feeder slot in the head (ask Tippie!!), caused by the holes in the top cover being too close together - always good to check - I filed mine slightly to allow fitment of thin gauge wire between stud and slot-side of their respective holes in the head. It just guarantees oil flow when everything is bolted up - get it wrong and it can prove VERY frustrating and equally expensive.

I'll probably go the SFC pump next build, but really, I think I've proven that a std system can work.
 
Ron, they are the most exquisite headers I have seen, visually, for a sf, ever....
Click to expand...

I bought them from Slater Bros CA back in 73 and there still on the bike. Big tube and the chrome is excellent. I did some exhaust porting to match the pipes with a slight reversion dam. The main reason I replaced the stock DMC pipes with these Rt-Side 2 into 1 pipes was to save weight and allow me room to fabricate rear sets.

Slater offered them as custom made and were worth $150 at the time.

I see these Pipes used on eBay from time to time; however, I believe a European Custom Shop still makes them and can't say if they are chromed.

One time rounding a hair pin when meeting a neighbour in his emaculate Black and Chromed 66 Chrysler 300 2 Dr-HT, I spit the baffle out and bounced it off his drivers door putting a small dent in his door. I felt bad as I did blip the throttle to show off but never expected to throw the baffle. I helped him repair and paint his door and since then I use a screw through the end of the cone to hold the baffle in place.

I replaced the stock 125 VHB 30 A main jets with 134's. If you don't that you risk leaning the mill out and holing a piston.

As I said, anything to do with Breganzie 750, I will Butt End.
 
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