Raveydavey wrote:It might have been me coming up Pytchley road. You can tell it's me by the noise
'She' sounds really fit! VERY torquey, pulling from nothing, fuss free. You must be aching from grinning
I've never owned a SI or SII, but freely admit that the curvy bodywork has grown on me, & if the money & time were mine, I'd love to ride a passionate 'unrestricted' Seniorita (
) once more, in two wheel form.....I must go for a lie down
As we are on the subject of seals, does your engine have the mag-side seal fitted? In other words, does it run the roller bearing in grease or petroil? Much depends upon the belief (or not!) in crankcase compression, but a reed valve engine such as yours might stand to benefit from having lower crankcase compression, which has the knock-on effect of giving the remaining drive side seal a slightly easier life. Just a thought, & nothing new to some of us
I hope this makes sense, but my belief is that if a crank is only a little twisted, then it will pump oil via the drive side seal journal, as you found, only over
part of the rev range. Once the revs increase, & the crank starts to flex (as it should) then that appears to stop the seepage as the seal is 'too busy' coping with the flex to let oil past. That is partly the reason that I have gone back to Nitrile, because I believe that it's material properties enable it with more flexibility. I reckon that had your seal been Viton, it would not have endured so well as the Rolf seal!
Call me outspoken, or cynical, but there are a lot of products that people buy into because of unproven or ill-founded scaremongering, or simply the Kudos! I wonder if I am alone in considering that the profit margin of Viton over Nitrile might come into why they tend to be sold.....
The journals that oil seal lips run on should be a surface texture that can retain oil, to stop the lip from wearing out. Scotchbrite is our friend when we install crankshafts, rather than polishing. Sometimes, dependent upon which power transmission stockists I order from, some seals have arrived with twin lips, which I tend to keep for those journals that might have wear evident, reasoning that there should be a void of lubricant retained twixt the two.