In tech talk it’s called “Bottom end rebuild”. Inspecting and/or replacing all internal crankcase components: how to get it done.
An engine’s internal components rotate at very high speeds; so they are mounted on spherical elements (balls and roll cages) that facilitate their co-rotation and reduce friction between them.
All of these “facilitating” components need to be inspected on a regular basis, to avoid wear and tear that culd lead to serious engine failure.
There are no particular signs of evidence for when it’s time to “renovate”: if you notice a “symptom” it’s always too late. So, the rule is to replace ball bearings and roll cages regularly, according to the factory-recommended maintenance schedule.
This is a very complex operation that is usually best left to a prefessional. If you’re not an expert, the risk of installing the bearings the wrong way, compromising shaft rotation, or not getting a perfectly straight shaft is very high.
Besides, you have to be able to open up the engine and, ideally, take out the clucth mechanism (it makes the whole process easier).o this is how it’s done, if you’re a pro, or fell oike one. After “opening” the crankcase...
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