good rod ends

[chall]

All the rod ends I bought this year were junk. None were tight after 50 laps. So my question is who makes good rod ends and who sells them?
Thanks
Chris

[Tim Lewis]

The best US source for Rod ends that I know of is Aurora bearing. They are in Aurora, IL. Their number is (630) 859-0971. They sell several levels of quality. How nice you want it??? How thick is your wallet?

[John Learmonth]

quote:

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Originally posted by chris hall:
All the rod ends I bought this year were junk. None were tight after 50 laps. So my question is who makes good rod ends and who sells them?
Thanks
Chris

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I don't know brand names, but any rod end with a Teflon insert (bearing surface) will probably last a LOT longer than a rod end with a bronze insert (which is the most common type on karts). The only reason bronze bushed rod ends are used is because they’re cheap, expect to pay at least double for Teflon (worth it).

Even though the teflon is softer than the bronze, it still lasts longer because this kind of rod end is 'self wiping', meaning that the edge of the teflon insert 'wipes' the dust etc off the sphere as it moves, keeping the abrasive particles out from between the bearing surfaces. The bronze inserts don't do this (ie keep the dirt out), and if you oil them the oil actually traps dust / grit which turns into grinding paste....

Teflon rod ends are self lubricating too, but even so are somewhat tighter than bronze, however you won’t even notice this from the driver’s seat. I know Swiss Hutless use teflon lined rod ends as standard equipment, I'm sure some others must as well.

[Erik Frank]

In the Aurora line up, the best quality ones are their Performance Racing Series (PRM part numbers). They are 3 piece construction, with an alloy steel housing. Teflon liners are available (-T suffix).

Generally speaking, the Aurora PRM rod ends are the best quality at a resonable price. To get anything at a higher quality, you are looking at aerospace grade and mil-spec parts, and the price goes up VERY sharply.

Other quality manufacturers are Heim, New Hampshire Ball Bearing, Seal Master, and Kahr.

I have examined data from high cycle fatigue testing on rod end connections, and it was empirically determined from these test results that you should apply an 80% reduction in the published radial ultimate static strength when sizing a PRM rod end for infinite fatigue life. This was using a double shear connection and 100% oscillatory load about a zero mean (no preload).

On a kart, your two biggest limiting factors will be impact loads and grit. You can also get seal boot washers for rod ends to protect the ball and keep grit and dirt from entering the bearing.

Hope this helps,
erik

[ December 10, 2001: Message edited by: Erik Frank ]

[John Learmonth]

quote:

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Originally posted by Erik Frank:
).

On a kart, your two biggest limiting factors will be impact loads and grit. You can also get seal boot washers for rod ends to protect the ball and keep grit and dirt from entering the bearing.

Hope this helps,
erik

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The cheap rod ends as mostly used on karts are intended for use on machines like printing presses (so I've been told). I've never seen one break except in an accident that also at least severely bent the tie rod itself as well. The loads seen in normal use aren't really that high, even considering the odd bit of wheel banging.

[Erik Frank]

John,

I agree with you about the failure mode. Most of the time the tie rods bend or buckle after a severe impact. It takes a lot of load to completely fail an 8mm rod end. Most rod ends used for tie rod applications on a kart are usually plenty strong. Also, when I said "impact" I also meant just the normal, typical racing wheel loads (curbs, bumps, etc.) These loads will eventually wear out a rod end, because they often exceed the lower fatigue limits I stated in my post above. It is a cummulative effect.

However, rod ends with bronze inner races are notrious for "pounding out" the inner races and getting loose. They have a much lower dynamic fatigue life. I will not use these on my own kart.

-erik

[ December 07, 2001: Message edited by: Erik Frank ]

[John Learmonth]

quote:

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Originally posted by Erik Frank:


However, rod ends with bronze inner races are notrious for "pounding out" the inner races and getting loose. They have a much lower dynamic fatigue life. I will not use these on my own kart.

-erik

[ December 07, 2001: Message edited by: Erik Frank ]

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Erik,
I do use bronze insert rod ends on my own kart (even though I don't like them) because I've made a simple tool that allows me to tighten the wear up between race meetings. I give them a squirt with carby cleaner (clean the crap out) and then tighten them up with this tool, takes about 3 minutes.

If I tighten them too much I can firmly tap them on the outside of the ball housing with a hammer, which 'pounds' them out (loosens the ball by spreading the bronze inserts further apart in the housing). I think the loosening you see in use is caused more by wear than than from being 'pounded out', I don't think the sort of impact they see in use is 'sharp' enough. But I could be wrong!

[Gary Kalan]

Chris,

I have been using teflon lined rod bearings for quite a while on my enduro kart with great success. They remain tight and therefore retain toe settings. The type I use are Aurora 5x16 X 5x16 with the following numbers:
Right Hand Rod End - VCM-5
Left Hand Rod End - VCB-5

I purchase them from the following F2000 shop:
Continental Motorsport
Continental Crossle Inc.
7535 Easy Street
Mason, Ohio 45040
(513)-459-8888
(513)-459-8863 (Fax)

Their numbering system is the following:
Right Hand Rod End - HA CMV-5
Right Hand Jam Nut - AN316-05R (5/16-24)
Left Hand Rod End - HA CBV-5
Left Hand Jam Nut - AN316-05L (5/16-24)

They will ship. Tell them Gary sent you.
I hope this helps!

[Mike Goebel]

quote:

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Originally posted by Gary Kalan:
Chris,

Right Hand Rod End - VCM-5
Left Hand Rod End - VCB-5

Right Hand Rod End - HA CMV-5
Right Hand Jam Nut - AN316-05R (5/16-24)
Left Hand Rod End - HA CBV-5
Left Hand Jam Nut - AN316-05L (5/16-24)

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Is it VCM-5 or CMV-5
Is it VCB-5 or CBV-5

Mike G.

[Gary Kalan]

Mike,

The actual number printed on the rod end itself is:
VCM-5 for the right hand rod end
VCB-5 for the left hand rod end
The other numbers that I quoted
HA-CMV-5 for the right hand rod end
HA-CBV-5 for the left hand rod end
are those used internally by Continental Crossle for the same rod ends. Hope this eliminates the confusion.

[Gary Kalan]

Mike & Chris,

Forgot to mention that the cost per rod end was approximately $6.00.

[Mike Goebel]

quote:

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Originally posted by Gary Kalan:
Mike & Chris,

Forgot to mention that the cost per rod end was approximately $6.00.

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Sweet, I got some for $13 ea from another kart store shop and they were suposed to be Aurora good ones and there not.

Mike G.

[Tim Paul]

Chris,

Do you make sure that the tie rod can rotate after the jam nuts are tight?

I have a CTS and when the jam nuts are tight I can move the tie rod at least 30deg with the steering wheel in a neutral position and at least 10-15deg throughout the whole steering rotation.

If you dont have at least a little rotation thoughout the whole steering movement the rod ends will bind and pre maturly wear.

I turn both rod ends forward or rearward before tightening. This will also prevent the rod ends from moving when tightening the jam nuts if you rotate them in the proper direction.

Hope this might help.

Tim

[chall]

Tim, that is one thing I am very carful about. I cut one up a couple of weeks ago. Seems to be a case of poorly made parts. The play seems to be from the cups walking out of the outer housing. I have never seen it before and don't intend to see it again. Thanks every one for your input, I learned a lot about rod ends.
Chris

[Rick Hiland]

FYI

Aurora Mild Steel Metric teflon lined 8mm x 1.25 are:

MM -M8T right hand $10-$12 price range +/-
MB -M8T left hand

Aurora Alloy Steel Metric teflon lined 8mm x 1.25 are:

AM- M8T right hand $18-$20 price range +/-
AB- M8T left hand

We have used these for the past several years and have not had to replace any due to wear.