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Quote from: Niels Abildgaard on July 19, 2014, 05:30:18 AMPlease let us see a picture of crankshaft ,bearing and Coupling.What is mass of piston plus pin?.The reason that You do not need needles in the upper conrod eye is that at 30000plus rpm piston is lifting against combustion pressure so that oil can come under pin.For normal speed two stroke this is not the case .wrist pin (solid in the middle) .250" OD- 5 gmspiston- 15.6 gmsJim Allen
Please let us see a picture of crankshaft ,bearing and Coupling.What is mass of piston plus pin?.The reason that You do not need needles in the upper conrod eye is that at 30000plus rpm piston is lifting against combustion pressure so that oil can come under pin.For normal speed two stroke this is not the case .
Jim if I read this correctly you said you ran your engine on the dyno for 4 min at 30000rpm. That in its self is impressive. I have no doubt you will be on top of the competition in 2015.
Hi JimThank you very much for your explanations - they do clarify some of my questions So if I see correctly - the way you put the cylinder inside the brass + PVC combo, prevents the electrolyte from coming in contact with anything you do not want plated - kind of what I expected, but didn't see on the first pictures, the additional helped quite a bit.So you're telling me that the major difference between "normal" chrome and "hard chrome" is down to temperature and current density in surface of the object - nice to know, again thank you.I can't help another question about this subject - is it always necessary to grind the cylinder afterwards or is that purely down to the extreme small tolerances you need in this engine size ?Again thank you very much for enlightening us - it's really appreciated Best wishesPer
Well I am in awe of the quality of your work ,which is of course backed up with a great depth of technical knowledge Sir I take my hat off to youI thought we were doing ok when we sorted out the veco 19 for car racing but after reading your thread we were only scratching the surface but we had to go to 95% nitroNow I know we were only on the title page not Evan the first paragraphStuart
Chromed cylinders must be finished afterwards because the chrome builds up thicker near the corners of the ports. http://www.electro-coatings.com/effects-of-electroplating.php If you look closely at production liners you can see this.Greg