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[Lever]

i have been noticing lately allot of talk about lifter failure and i wondered if its caused by all these new radical cam profile's
 that's causing for a split second the lifter's roller is actually coming off the cam lobe then it slams back down causing a flat spot which in time causes the lifter to flake .chunk off etc
i have seen video's on you tube with valve springs dancing  you would swear how does that motor still work

[bikerboy53]

Not sure if it's the cam profile or not. One of my friends recently changed out the cams in his stock 96 ci motor and found that one of the rollers was starting to flake/come apart. Luckily he caught it before it did much (any?) damage.

I've also heard it blamed on excessively strong valve springs. Seems like it's more likely to be inadequate hardening or heat treating of the rollers, or the wrong material for the rollers, or something along those lines. Just my guess tho... Anyone else have opinions on the cause?

[prodrag1320]

ide agree with wrong hardness/material used on rollers.but have seen exessive spring pressures cause probs too.alot of engine builders just automaticly use brutal pressure springs on every build with a cam over .570 (or whatever) lift.we use ONLY the pressure required for each build/cam being used

[grc]

There have been recent reports of the actual roller surface delaminating/chunking, which is not the traditional failure mode I'm familiar with.  That sounds like just poor quality material or heat treating.  The more common problem in the past was failure of the axle and needle bearings, and that can be caused by cam profiles, heavy spring pressures, etc.  If the combination allows lofting, the resulting pounding will deform the needles until they no longer roll.  Lack of lubrication to the bearings is also a concern.

Jerry

[HILLSIDECYCLE.COM]

ide agree with wrong hardness/material used on rollers.but have seen exessive spring pressures cause probs too.alot of engine builders just automaticly use brutal pressure springs on every build with a cam over .570 (or whatever) lift.we use ONLY the pressure required for each build/cam being used

Right on.
No need for wild seat, or nose pressures, but rather the correct pressure, as needed.
Scott

[kraut]

those pics from my last lifter problem seem to support Jerry's theory: