Tapered Roller Bearings - Karting


New member
PD - your lack of proof other than vague muttering about an incident doesn't change anything either.... Posting the mode of failure would. Anything that causes the removal of a wheel on a racecar while at speed results in bad things....but I'm not convinced the bearing style is to blame unless the rollers welded together, broke the cage, and went flying out, causing the wheel to separate and fall of.... So, what really happened

So what really happen we all want to know.

PD Power

New member
I just perused this thread again.....I intend to make this my last post on it. I certainly did not intend to get into such a rancorous discussion.

The example I've given......On of our pro-type racers, engine builders, setup experts in karting is Vic Peters.
Running the tapered bearing set, he had the experience of having the cotter key break.....the nut back completely off the spindle, and the angle which the tapered bearing runs on, spit off the wheel, like spitting out a pumpkin seed.
It was a horrific accident, in which he had to be helicoptered from the track to Tampa General hospital. (I believe it was Tampa General).
It was a life threatening deal. Why the cotter key broke....or even conceivably was not in there, is not known by VP or myself.

What we DO know, is that there is no lap time reduction, using the tapered bearings.
I tested them THOROUGHLY on a Raptor plate engine, on a paved 30 second road course, with turns, right and left....and significant straightaways.
This was with a driver who ran that course so frequently....never with anyone else on it, and lap times ran within 5 hundredths all day long.

The standard bearing setup was no better or worse than tapered. I DID loosen the standard bearing adjustment, by backing off the nut a few threads, then using the
nut retainer and cotter key, and having a lap run, then checking for the condition of the bearing, etc. in the hub. The bearing had not moved out against the nut......and the
driver recorded no driving issue whatever.
The setting on the tapered bearings is critical, because if it moves so much as a thread, the taper pushes the wheel horizontally which moves the wheel vertically and off the spindle. And YES, this is usually caused by a mistake in mounting the bearing, hub, or something of the sort.
I do not believe that there tapered bearings have a danger factor at all.....unless something unforseen happens.

As a traveling gypsy/professional racer, we always believed in trying to cut down on the percent of chance, for something to go wrong.....and have a serious result.....loss of health or life.

Example: My friend Dick Harrell, got killed when a front tire came loose from the rim on his injected fuel funny car. No one has ever explained why this happened.
VP nearly bought the farm when his RF wheel left the kart.....at full speed. No one knows to this day, if the cotter key sheared, was not installed or whatever.

As I recall, Tony Bettenhausen Sr. died from loss of a wheel, generally blamed on missing or broken cotter key. They used tapered bearings.
In the 1987 Indy 500 the RF wheel came off Tony Bettenhausen Junior's car and killed a spectator.

Kermit Buller made and sold tapered bearing sets.
He told me straight out, that there was no advantage to the tapered bearing set, and that he had...himself...tested them against ball bearing
and could not find any advantage in the taper set.

So.....if one of the respondents to this wants to say that this is just BS.....like....."I hit my finger with a hammer, so outlaw hammers".....I have
no response for such illogical, disingenuous examples.

As for myself and the karts I am involved with, we will try to cut the percentages of unnecessary track incidents down....while racing as hard as we can.

I hope this brings my participation in this discussion to a halt. I cannot think of something more to add to my thoughts on this matter. I have no personal
stake in this discussion. Only what we do matters to me.

http://skclinton.dreamhosters.com/?page_id=142 This is a really interesting study of what happened to Bill Vukovich Sr. in the
1955 Indy 500 in which he died, leading the race, going for his 3rd straight Indy 500 win.
(Has nothing to do with the discussion on this thread)


If the spindle nut comes loose....the bearing shoots off the end of the spindle.
One of our very best racers had to be air lifted to the hospital......SERIOUSLY injured when that exact thing happened.

Furthermore that tapered bearing idea is not exactly new. It has tested exhaustively for years. It offered exactly NO value to corner
speed or handling.

That does not sound like the bearings fault... More like lack of maintenance to me

PD Power

New member
That does not sound like the bearings fault... More like lack of maintenance to me
Stated earlier, it's NOT the bearings fault. It's the design of the bearing which allows this to happen when every maintenance issue, or any fault in the cotter key, for example, happens.
Since there is no proven value to the taper bearing....someone tell me....WHY USE THEM?? Is this such a difficult concept to think out??
P.D. you are beginning to sound like Al;, if you had ever raced an enduro kart, then you'd know that they are recommended for karts that have front brakes.


Tapered bearings for karts have been around forever. More so for the front than the axle. I don't think they are faster than rollers, my opinion. Here's the thing, there are races for $2,000 to $10,000 almost every weekend. Now if tapered roller bearings were faster I guarantee you the winners would be running them. Also no matter the cost some kart manufacturer would be offering them.

If they were unsafe the government would have banned their use years ago.


Quote["They pose a significant safety issue, when used on the front wheels, and ought never to be allowed on the front (steering) wheels." ]

Well, if anyone tells the trucking industry that those 80,000lb trucks on the highway traveling at 70-80mph have tapered roller bearings in the front hubs on the steering axle, then this country will come to a stand still. We were talking about Karts, then you want to bring up a Funny Car that lost a tire. Did the wheel bearing cause this? Also, I have never seen a Kart with as much down force as an Indy car, so all in all Paul....I think we're pretty safe. And I can tell that the tapered roller bearings in my laydown enduro do roll thru the corner better. They take a better side load than a sealed ball bearing and I run a heck of a lot faster at Road America than those on a dirt or paved oval.