I swap to six start gear and worm, move the top end feed to the high pressure side (instead of return) and swap from scrolled spindles to plain.
I have only done this on our two Dommies because when I was rebuilding the heads, I found the spindles were worn and needed swapping anyway.
There is nothing wrong with feeding the top end from the return and using scrolled spindles - the oil feed rate is adequate.
I have the 6 start oil pump with rocker feed from oil return line, and do not have over oil feed issues. I also have the con rod squirt holes ... how the 6 start pump and squirt holes occurred on a '62 factory build Atlas is a mystery.For me, using the high capacity pump with six start makes sense - it became standard on the Atlas anyway, and is a great way to circulate more oil around the engine.
If you do swap to a six start, but leave the rocker feed on the return side, just keep an eye out for over oiling the top end.
Controlling the feed rate to the top end relies on the restriction at the "t piece" on the return line - it is easy to restrict it a little more if you find you are over oiling the top end.
Besides narrow gears for all early NHT with 1.5" crank and the later full width gear starting with the 1.75" crank (650), who makes and sells a "bigger"pump?bigger pump
Re; Con rod squirt holes, - this was first used on the Commando, but Norton later issued a press bulletin stating that the big end sheels should be turned around so that they blocked the oil holes.I have the 6 start oil pump with rocker feed from oil return line, and do not have over oil feed issues. I also have the con rod squirt holes ... how the 6 start pump and squirt holes occurred on a '62 factory build Atlas is a mystery.
Slick
TSI have the 6 start oil pump with rocker feed from oil return line, and do not have over oil feed issues. I also have the con rod squirt holes ... how the 6 start pump and squirt holes occurred on a '62 factory build Atlas is a mystery.
Slick
My oil junction block has 5/16" OD tubes. The internal passages in the case are 3/16" dia. if my memory serves me correctly.TS
The reported racing effort says there was 6 start gears quite early for NHT. Some early singles has 6 start except the "gear was thinner". I'd assume that meant the crank gear. Would it still have worked on a twin? IDK?
Is your case fitted with the early small diameter junction block hardware?
I guess I could make my oil pump tester case into small inlet for a flow rate test comparison.....does the size really alter the flow rate enough to matter?
Inquiring minds want to know the truth instead of rumors...
Now what are you jibbering about and some of the advisce you been given is totally wrong and heres why now to use the six start oiling system you need to change some crucal parts like big end shells with oil holes in then and pain rocker spindels too so its a major stip down and rebuilt with the appropret parts so if I was you I would stick too the 3 start oil system if its good enough for a 650 and 750 atlas is ok for your bike just use good oil like a good 20/50 will be fine I have done thousand of miles on 20/50 and raced on it tooFor me, using the high capacity pump with six start makes sense - it became standard on the Atlas anyway, and is a great way to circulate more oil around the engine.
If you do swap to a six start, but leave the rocker feed on the return side, just keep an eye out for over oiling the top end.
Controlling the feed rate to the top end relies on the restriction at the "t piece" on the return line - it is easy to restrict it a little more if you find you are over oiling the top end.
Sorry, but the oil holes in the big ends shells is OLD ADVICE!!!.Now what are you jibbering about and some of the advisce you been given is totally wrong and heres why now to use the six start oiling system you need to change some crucal parts like big end shells with oil holes in then and pain rocker spindels too so its a major stip down and rebuilt with the appropret parts so if I was you I would stick too the 3 start oil system if its good enough for a 650 and 750 atlas is ok for your bike just use good oil like a good 20/50 will be fine I have done thousand of miles on 20/50 and raced on it too