Ceramic Bearings

[MaxPower]

Does anyone have experience using ceramic bearings? I am going to install a fresh set of mains in my 125 and was wondering if there was any advantage with performance or longevity?

[Lozza]

Yes Yes and Yes ..............but with a disclaimer when you have fully optimised the engine then you can go to ceramics. If you haven't fully optimised the engine you won't get the benefit. Beware do not buy any zirconim(or whatever they are called) white coloured balls they will last minutes. Avarage cost of a crank main is $100 USD

[Tomas]

Not sure if there is anything to gain from using ceramic bearings. Just use correct type  bearing from reputable company and make sure that they get plenty of lube. I use centre drill to open crank bearing  lube canals in engine cases so the end looks like a funel. This will get more oil into bearing. Doing this increases catchment area of the lube hole 2-3 times. Just like having 8mm lube  hole in crankcasese instead of only 4mm. Done this on 2 motors and never had a spun or siezed bearing. One motor is running just regular not c3 bearings with no dramas.

[Lozza]

Not sure if there is anything to gain from using ceramic bearings. Just use correct type  bearing from reputable company and make sure that they get plenty of lube. I use centre drill to open crank bearing  lube canals in engine cases so the end looks like a funel. This will get more oil into bearing. Doing this increases catchment area of the lube hole 2-3 times. Just like having 8mm lube  hole in crankcasese instead of only 4mm. Done this on 2 motors and never had a spun or siezed bearing. One motor is running just regular not c3 bearings with no dramas.

Dynos and stop watches don't lie. Too much oil and balls will start to skid. Why run normal clearance bearings on the crank mains when C3 is no more expensive? On GP engines C4 is standard and old Formula A kart engines (100cc fixed gear rev to 22,000 rpm) C5 was needed

[Tomas]

Not sure if there is anything to gain from using ceramic bearings. Just use correct type  bearing from reputable company and make sure that they get plenty of lube. I use centre drill to open crank bearing  lube canals in engine cases so the end looks like a funel. This will get more oil into bearing. Doing this increases catchment area of the lube hole 2-3 times. Just like having 8mm lube  hole in crankcasese instead of only 4mm. Done this on 2 motors and never had a spun or siezed bearing. One motor is running just regular not c3 bearings with no dramas.

Dynos and stop watches don't lie. Too much oil and balls will start to skid. Why run normal clearance bearings on the crank mains when C3 is no more expensive? On GP engines C4 is standard and old Formula A kart engines (100cc fixed gear rev to 22,000 rpm) C5 was needed

Well Max mentioned 125cc motor. So I am guessing it may be a vintage bike that would be raced in some sort of vintage race or just riden for fun. I guess 125 may rev up to 10-12 thousand rpm not 20 thousand. Sure he is not going to use a new motor or two every season and few hundreds of second makes no diference when you  racing or riding 20-30 years old motorbike. Also I am not talking about pouring oil on bearings. Remember those bearing use bit of oil disolved in gas to keep them oiled. I have never tried ceramic bearings in 125, just a regular ones. Have you ever run ceramic bearing in an average 125 motocrosser Lozza?
And running regular not c3 bearing is more of an experiment for me. There is a loot of people here on this forum that like to talk about something they have never tried. That is why I do not participate much here, just like lot of others. Good luck with ceramic bearings Max

[Lozza]

Well Max mentioned 125cc motor. So I am guessing it may be a vintage bike that would be raced in some sort of vintage race or just riden for fun. I guess 125 may rev up to 10-12 thousand rpm not 20 thousand. Sure he is not going to use a new motor or two every season and few hundreds of second makes no diference when you  racing or riding 20-30 years old motorbike. Also I am not talking about pouring oil on bearings. Remember those bearing use bit of oil disolved in gas to keep them oiled. I have never tried ceramic bearings in 125, just a regular ones. Have you ever run ceramic bearing in an average 125 motocrosser Lozza?
And running regular not c3 bearing is more of an experiment for me. There is a loot of people here on this forum that like to talk about something they have never tried. That is why I do not participate much here, just like lot of others. Good luck with ceramic bearings Max

Obviously you missed what I posted here?

Yes Yes and Yes ..............but with a disclaimer when you have fully optimised the engine then you can go to ceramics. If you haven't fully optimised the engine you won't get the benefit. Beware do not buy any zirconim(or whatever they are called) white coloured balls they will last minutes. Average cost of a crank main is $100 USD

I have used ceramic bearings in vmx bikes. It will make a big difference if there are 2 equal riders on board that both want to win, be it a race,meeting or national title. Ask your bearing shop about over oiling bearings.

Professor Carl Bite- you   from the east cost apparently has done conclusive tests with ceramic bearings  on his home made dyno . So far all inconclusive ....

If there was nothing to them why do they sell so many, our dyno doesn't lie nor does the stop watch.

[Tomas]

Over oiling? At 20 to 1 that is 5 percent of oil  that has reduced lubricity by being disolved in gas. Good luck with ceramic bearings Max.

[Rossvickicampbell]

I would of thought your changes if they had been so good would of been adapted by the factories - surely there is a reason why the "canals" are the size they are - or did the factories completely cock it up Tomas?

[Tomas]

So why bother porting engine cylinder to improve/increase fuel flow for example. Is it because all the cylinders are cocked up from factory?  And on and on and on. Ha ha

[pokey]

i suppose we could use a fire hose on a swimming man , that would make him swim better?

optimisation of engine or for that matter any component is specific for the intended use. Extreme performance requires extreme components that have many hours R&D behind them by learned engineers. Installing those components in a garden variety machine usually have little to no benefit in the action and an adverse effect on the wallet.

The first notion that should enter the head during a pondered modification is. "What is its intended end use"

tear offs on your goggles are good but spacemen dont need them.

[William Doe]

How much REAL DIFFERENCE do any such mods make ON THE MX TRACK to the average VMX wobbler 

I wont argue for or against ceramic bearings or bigger oil galleries as I have NFI . I enjoy other peoples input though and learn a thing or two from these debates .

But at the end of the day I doubt very much that any such mod will make a difference to the average VMXers results even in a 125 .

How many of us can honestly say that we use all that even  a std 125 produces ? im not talking about holding it flat out down a straight ( you can teach a Chimp to do that ) this is MX not drag racing .

Better suspension ( put that power to the ground ) and brake .5 of a second later going into every corner and wind it on .5 of a second earlier coming out of every corner , 10 corners a lap = 10 seconds a lap improvement , 5 lap race and your nearly a minute in front of ole mate with his ceramic whatnots   

 

[yamaico]

Dynos and stop watches don't lie. Too much oil and balls will start to skid. Why run normal clearance bearings on the crank mains when C3 is no more expensive? On GP engines C4 is standard and old Formula A kart engines (100cc fixed gear rev to 22,000 rpm) C5 was needed

Too much oil certainly doesn't cause balls to skid. Gearbox bearings run in a bath of oil, crank bearings run on a drop of oil. Lack of lubrication can cause balls to skid, particularly in a differential load situation such as an engine.

[djr]

I would of thought your changes if they had been so good would of been adapted by the factories - surely there is a reason why the "canals" are the size they are - or did the factories completely cock it up Tomas?


That's a good point about the factories , so maybe the factories don't fit ceramic bearings for a reason ?

[skypig]

There are many reasons to modify from stock.

Maybe the factory's don't fit ceramic bearings for cost reasons. Maybe they feel they are less reliable or not as long lasting.

In a fascinating book on GP engines I read: there was a story on a factory fitting bigger (main?) bearings on their new race engine. The problem was the bigger bearings failed more quickly. They learned the greater inertia of the larger balls promoted skidding, especially at high rpm. Another advantage of Ceramic bearings (lighter weight) I'd imagine.

[micks]

sorry for the hi jack but mains with the plastic cages are they ok or keep the steels in mains