- Joined
- Oct 19, 2005
- Messages
- 18,978
Norton rod piston oil jet holes are as useful as tits on wild bores or the little lost toe scars up inside of horses legs. Norton twins has piston sezures as engines increased in size/power so they assumed lack of wrist pin lube but later found out to be bad batch of pistons but the batch of rods ordered already had the hole drilled...
Japanese research shows it take 0.6 liters a min. in pistons our size to cool crown 100'F. If the brief twice a cycle spritz, of which only the one on decending piston can reach the pin area ever prevented a seizure it was d.t wrist pin lube but nothing to do with any cooling. Old Ducati's and many others put a notch or 2 in sides of rod big end so they spray continuously upward out of shells crank sling to get a good bit directed up so piston can collide with it on down strokes. Its was/is still common practice for racers to block Norton oil holes and they don't seem seizure prone doing so. On the other hand as so little oil lost twice per rotation its basically a non issue either way. HD did lots of research on oil cooling heads to trash the idea as didn't cool head temps at all but fired the oil w/o a car size radiator.
Carrillo offers tiny oil spriz'ers
http://www.cp-carrillo.com/Tech/RodTech ... fault.aspx
Effective rod big end shoulder notches spraying up full 360' of rotation. Can be made at top center or staggered either side of center on either side of big end.
http://www.astraownersclub.com/vb/showt ... zlet/page2
http://www.turbosport.co.uk/showthread.php?t=142503
As with all prototype parts, we ran into some small glitches. Carrillo left out the oil jet notches from the thrust faces of the rods (an oversight in trying to get us the rod as quickly as possible). These are not present on the stock rods because Honda incorporated an oil jet into their beam design to spray the pistons with oil to keep them cool.
Japanese research shows it take 0.6 liters a min. in pistons our size to cool crown 100'F. If the brief twice a cycle spritz, of which only the one on decending piston can reach the pin area ever prevented a seizure it was d.t wrist pin lube but nothing to do with any cooling. Old Ducati's and many others put a notch or 2 in sides of rod big end so they spray continuously upward out of shells crank sling to get a good bit directed up so piston can collide with it on down strokes. Its was/is still common practice for racers to block Norton oil holes and they don't seem seizure prone doing so. On the other hand as so little oil lost twice per rotation its basically a non issue either way. HD did lots of research on oil cooling heads to trash the idea as didn't cool head temps at all but fired the oil w/o a car size radiator.
Carrillo offers tiny oil spriz'ers
http://www.cp-carrillo.com/Tech/RodTech ... fault.aspx
Effective rod big end shoulder notches spraying up full 360' of rotation. Can be made at top center or staggered either side of center on either side of big end.
http://www.astraownersclub.com/vb/showt ... zlet/page2
http://www.turbosport.co.uk/showthread.php?t=142503
As with all prototype parts, we ran into some small glitches. Carrillo left out the oil jet notches from the thrust faces of the rods (an oversight in trying to get us the rod as quickly as possible). These are not present on the stock rods because Honda incorporated an oil jet into their beam design to spray the pistons with oil to keep them cool.
