Ceramic bearings?

Discussion in 'General Questions' started by Frankenstein, Sep 9, 2016.

  1. Frankenstein

    Frankenstein Well-Known Member

    This might be a question for @jaguar, anyone tried using ceramic main bearings in a 2 stroke? I know they can be not so good with high vibration, but a trued and balanced crank could probably be good on full ceramics. They might not be beneficial at lower rpms like in bicycle wheels but at the high thousands they are supposedly better.

    You think it's a good idea? I'm looking at buying a grubee, swap out main bearings for ceramics. Then port out the top, balance the crank jag style, perhaps buy a jag cdi, and jackshaft it with a nuvinci into a schwinn Stingray.

  2. butre

    butre Well-Known Member

    look into abec ratings. ceramic bearings are a nice thing sometimes but have a very niche application that don't match what an engine requires. you're looking for a higher abec rating, not some shiny new paragon of materials.

    my advice is not to exceed abec 5 in a high speed high heat application like a motor
    Last edited: Sep 9, 2016
  3. Steve Best

    Steve Best Well-Known Member

    Better suited to high speed and heat applications like a turbocharger.
    Regular C3 grade ball bearings will handle everything these motors can throw at them.
    The rod and wrist pin bearing could use some help, mainly a better grade of roller bearing.
    We would be talking $20 each instead of the present $4.99.
    Then maybe we should get the cylinder nikasil coated, for about $250 if we want matching reliability.
    But now we are out of our target $125 engine price...
  4. Frankenstein

    Frankenstein Well-Known Member

    I don't recall my target price being stated as $125 or within reason..

    How good is a nikasil coating anyway? Heard of it but didn't put all that much thought towards it. Would it considerably outlast the current chrome plate? I know a cylinder is like 25 bucks or so, but if I replace a cylinder 10 times I must also port and polish 10 times...
  5. butre

    butre Well-Known Member

    you're better off getting a cylinder sleeved
  6. Frankenstein

    Frankenstein Well-Known Member

    I looked into sleeves, can't seem to find any that would work... Even a diesel sleeve would work I can cut the ports out myself. I guess the biggest problem is finding a small sleeve that will work on these pistons.

    Maybe just buy a few cylinders and port them, and stick them in the junk drawer untill needed.

  7. Steve Best

    Steve Best Well-Known Member

    Look into the cast iron Minarelli cylinder Frank. Koni Showa showed us the way.
    $50 for cylinder, piston, pin and all. There is a power aftermarket too.

    Aftermarket Nikasil is freaking amazing, quite thick and durable.
    You cannot port into it, so figure out your porting before getting them done.
    My son grenaded several YZ125 piston without putting a scratch into the Nikasil.
    The stock nikasil plating is very thin, but when the aftermarket plater in Quebec puts it on, it is tough.
    I am thinking of sending my damaged cylinders to them if I can cut a deal, say $100 to plate these.
    Standard MX cylinders are $250.