Britstuff
Basic
- Joined
- Jan 8, 2021
- Messages
- 212
Hi All:
I am toying with the idea of changing my low pressure drip oil feed to the head, to a high pressure one like on a Commando, (and other post '66 Norton heavy twins).
Is an upgrade to a six start gear and worm an essential part of the recipe?
Some back ground information:
It has been quite a long journey trying to get an adequate oil supply to the exhaust valve guides and tips. Have recently suffered sticking valves, a snapped exhaust rocker and major deformation to the top of the exhaust valves. Through it all intake valves have been just fine, plenty of oil, no problems. Funnily enough all was acceptable until I fitted an anti-sumping oil tap. I think the fact that the bike was wet sumped most of the time when I started it, caused a nice strong initial oil feed to the exhaust valves before the sumping was cleared. I suppose I could put my finger over the return hole in the oil tank for a minute or so whenever I start the bike. I'm just thinking why keep messing with it? I like my anti-sumping tap, My MKII 850 Commando runs so much quieter and without any problems with oil delivery to the head. I have a Norvil high Capacity, (whatever that means) oil pump fitted on the '62 Dominator. Still running the three start gear and worm. When I run a pressure gauge from the high pressure outlet, below the pressure relief valve, I get excellent oil pressure, (warm 20-50 psi).
A concern I have with my proposal is possible over oiling to the head. Being a '62 I am guessing the oil drain drillings are smaller than the factory post '66 hi pressure feed bikes. I assume we are talking about the single drilling oil drain for the intake valves - to my tiny mind it appears to be quite small.
Rockers are all in great shape. I would definitly install plain spindles with the flats correctly orientated. Oil feed to the head from the high pressure outlet, below the pressure relief valve. I already have inlet valve stem seals fitted. I'm just wondering if the six start conversion is a neccessity? some sources seem to suggest it is not, but, obviously I do not want to risk compromising oil feed to the crank.
I look forward to your comments.......
Many thanks!
I am toying with the idea of changing my low pressure drip oil feed to the head, to a high pressure one like on a Commando, (and other post '66 Norton heavy twins).
Is an upgrade to a six start gear and worm an essential part of the recipe?
Some back ground information:
It has been quite a long journey trying to get an adequate oil supply to the exhaust valve guides and tips. Have recently suffered sticking valves, a snapped exhaust rocker and major deformation to the top of the exhaust valves. Through it all intake valves have been just fine, plenty of oil, no problems. Funnily enough all was acceptable until I fitted an anti-sumping oil tap. I think the fact that the bike was wet sumped most of the time when I started it, caused a nice strong initial oil feed to the exhaust valves before the sumping was cleared. I suppose I could put my finger over the return hole in the oil tank for a minute or so whenever I start the bike. I'm just thinking why keep messing with it? I like my anti-sumping tap, My MKII 850 Commando runs so much quieter and without any problems with oil delivery to the head. I have a Norvil high Capacity, (whatever that means) oil pump fitted on the '62 Dominator. Still running the three start gear and worm. When I run a pressure gauge from the high pressure outlet, below the pressure relief valve, I get excellent oil pressure, (warm 20-50 psi).
A concern I have with my proposal is possible over oiling to the head. Being a '62 I am guessing the oil drain drillings are smaller than the factory post '66 hi pressure feed bikes. I assume we are talking about the single drilling oil drain for the intake valves - to my tiny mind it appears to be quite small.
Rockers are all in great shape. I would definitly install plain spindles with the flats correctly orientated. Oil feed to the head from the high pressure outlet, below the pressure relief valve. I already have inlet valve stem seals fitted. I'm just wondering if the six start conversion is a neccessity? some sources seem to suggest it is not, but, obviously I do not want to risk compromising oil feed to the crank.
I look forward to your comments.......
Many thanks!
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