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I was wondering how long it be before bearings replaced sleeves on the crank shaft, real nice work!
This is great, however, you might find drawbacks when you actually apply this to a consumer level application such as a normally driven car. I think that you will find it will be noisey under different operatting temperatures. Will this be acceptable to the general public? Also in the balance is the additional cost of assembly and parts. If these can be overcome it would be great!
Keep up the good work!
Dale Guenther
Everyone knows that needle bearings have less friction than sleeve bearings.
Sleeve bearings are used on crankshafts because the bearings are split to ease assembly. What is required to assemble and adjust needle bearings onto a crankshaft?
Also, unlike simple rotating systems, crankshaft bearings are subjected to transverse (combustion) impulses. How is the smaller contact area of needle bearings affected by this?
This new design might require larger journals to handle the same pressure on the crankshaft for contact pressure/area, but it's a great improvement. What is also needed is less drag caused by the piston rings on the cylinder walls. We have been so conditioned to use sleeve bearings as the only way to do something, I'm glad to see someone being inventive in this design. I'm aware of the difference between roller bearings for rear axles vs ball bearings as they differ in the amount of load each type of bearing can handle. This engine design may require wear analysis to see how these bearings wear under load and time. Maybe Carbon rings may have less friction if we can manufacture rings that can be installed and stand the pressure. We've tried various engine designs for years and keep coming back to the standard recipricating engine over and over. Hard to beat success, and reliability. But the heat generated in the engines tell us there is friction causing a lot of this heat, which indicates drag. Thanks for something new. Keep it up.
The needle bearing crank has been used for decades in high performance marine engines, particularly large two-stroke outboards. The improvement in efficiency is just as shown in the video.
What the purchasing public will demand is an equivalent cost, ease of repair and longevity.
We used to be able to buy needle bearing kits for VW engines back in the 70's.
We have been using needle bearings on both the crank shaft end and wrist pin end of small converted 2 stroke chainsaw engines for UAV's and large R/C model aircraft for years. Some of the high-end engines also use needle bearings on the grank mains. These little engines range from 25 cc to 250 cc and produce large amounts of HP for their size and weight. It's nice to see that the automotive guys are getting the message too.
I think I observed that the test engines in the short movie clip did not have the pistons and conrods fitted during the spin up tests. What is the % reduction in total engine rotational drag when all cmponents are fitted to the engines?
Graham, A reduction of friction is just that, a reduction of friction. It would be the same reduction with all the componets added.
John P. even though the contact area is smaller, there is a hugh difference in material hardness and reduced friction making the system much more robust.
A large advantage of journal bearings is longer life than antifriction bearings (needle and ball). If the oil is kept clean, the journal bearing will operate for many miles/hours. The engines that currently use needle bearings generally are shorter life engines in order to gain high efficiency and power output. Journal bearings are also more forgivening of impulse loading than antifriction bearings.
Outboard engines have split needle bearings on the crankshaft main journals, the connecting rods,& the the wrist pin for the piston are long needle bearings with caps on the end. Just think if we would build car engines this way & also put needle bearings on the cam journals, with roller lifter & roller rocker arms. It would be a completely rollerized engine.
Hey Guys,
Porsche had a roller crank back in the 50's. What do you think Honda and others are using on their racing engines.
Putting these bearings in consumer sector engines means exposing people, who hardly bother to change the oil and filter, to several thousand more moving parts! Think about that.
It seems contamination due to lack of maintenance, wear, and carbon deposits would have to be overcome to make this a viable solution but I love the concept...
for those who aren't able to discipline themselves to maitain wouludn't synthethetic lubricants/additives provide a longer time between oil changes.