A: Oil Pipework OP9/2 oil delivery quill - damaged?
- Thread starter Joe
- Start date
I think the most important thing is that oil is delivered to the end of the crankshaft.With rollerbearings there is no oilpressure and while the crankshaft is rotating it sucks all the delivered oil with centrifugal force into the crank.No seal like on BSA or Norton twins is necessary.Regards Erik
Ahh, I understand what you're saying. I knew that roller bearings require very little lubrication. It had escaped me that there is little too no pressure at the big ends as they are rollers vs the plain shell types on Triumph and BSA twins which require pressure to be maintained. So no need to worry about a highly effective seal at the input of the crank or even a bush.
Thanks
Steven
What you have is a quill that has been sheared off ,and then brazed back together.
some machines have main shafts that have the oil drilling drilled in the main shaft on the piss this places a side load on the quill, and can cause the to quill to shear.
this happened on Rogers twin. the only answer was to have the main shaft changes for one that had been correctly machined in the first place
You beat me to it Erik, the other bikes have plain bearings & require pressure to keep the surfaces apart. The series "A" Comet that I've hoarded for over 50 years is fitted with a homemade B/E bearing (floating bush) like Royal Enfield, I had a model "J" 350 for a short time while waiting for Alpha to fit another bearing ( three B/E in four years and rarely got more than 50k out of them)
Series "A's" have the advantage of a gear oil pump whereby the oil flow in constant supplying and scavenging more than a double start Picador pump (in his snarling beast by Roy Harper, Vincent wished he had kept it) I've altered the supply by half as much again by machining the pump housing an extra 1/16" deeper and fitting 3/16" wide gears, the scavenge is 1/4". Are any mathematicians out there to calculate the centrifugal pressure of the oil in relation to RPM.
Groove machined internally with herringbone channels nearly to the edge as didn't want to lose what little pressure there is to the inside and out surfaces which only need to travel half the surface speed of a conventional plain bearing. Vincent also went on about plain bearings RR77 in a Grey Flashes that failed on the TT bike but John Surtees went on to race his for a few seasons totalling approximately 6,ooo miles. The proof is in the eating.
bananaman
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The one I have used for about 12,000 miles that is worn that way. It hasn't been broken or repaired though. Some of the timing side crank pins are not drilled all that straight and it can cause the wear yours has. I guess really bad ones might even cause breakage of the quill. I have a new timing side shaft in my bike now and it is very straight. The one the flywheels came with was very crooked and it appeared it had run a very long time like that without problems. I don't think that it is necessary to have a really tight seal where the quill fits into the shaft. The rotation of the engine (centifugal force) must cause the oil to be sucked into the crankshaft. It isn't necessary to have a seal like on a Triumph or Norton where the oil pressure is way higher.
Thank all for sharing your vast experiences around the quill and it`s function.
As for now I`ll re-use as it has been in operation before and focus on getting some overall experience with the bike...
I`ll be attending later to the subject and turn a new one but will then need to closely monitor fit and wear to make sure it won`t be scraped or sheared off - mind me of subsequent damages ! -
Cheers Joe
As for now I`ll re-use as it has been in operation before and focus on getting some overall experience with the bike...
I`ll be attending later to the subject and turn a new one but will then need to closely monitor fit and wear to make sure it won`t be scraped or sheared off - mind me of subsequent damages ! -
Cheers Joe
15 January 2015
Worst item I ever saw from the 'barren years' was Ray Elger, he had a big end quill not drilled right through, of course Ray had checked it before using, others might not...
Worst item I ever saw from the 'barren years' was Ray Elger, he had a big end quill not drilled right through, of course Ray had checked it before using, others might not...