Crankbearing freeplay 2006 models

[Mikael]

Hi ,

Is it normal on bigger 2-stroke 2006 that you can feel sort of slight up&down movement on ignition side bearing or is it on its way to wear out ?

 

[gasmonkey]

Sooner than later it's gonna cost.
Just routine maintenance,no big deal.

 

[GMP]

Its normal on a roller bearing of that type, they run at much greater clearances than a ball bearing. Check a brand new bike and it will be the same. Just ride, don't sweat it.

 

[Mikael]

Hi Glenn ,

Is it normal also with warm engine ? What kind of crank bearing type allows such a freeplay , just wondering ? I have been learned by the years with absolute non up&down movement ?

 

[GMP]

Its a two part roller bearing, the inner race is pressed on the crank before the crank is installed, the rest of the bearing in the cases. (look at the service manual) Makes for easy disassembly, and is rated for a higher load. They run, by design, a higher clearance. This bearing is used on the ignition side since '02 or '03. KTMs have used them as well for some time. Again, its perfectly normal to feel this play, hot or cold. I've noticed it on both my '03 and '07 as well as KTMs. If the bearing was bad, it would vibrate and roar like a train, you would know it. If you were to feel the same play in an older ball bearing, then its time to split the cases.

 

[goose202]

Finding this thread has eased my concerns a bit. I noticed there was a slight up-down movement in the crank bearings on my '04 EC300 and was starting to get nervous that it wouldn't be just a re-ring coming up soon.

Once the clutch is depressed to take up the horrible clutch noise, the engine is nice and quiet.

 

[goose202]

According to the dial guage on the flywheel, my ignition side crank bearing has 0.025mm up-down play. I don't suppose that's anything to be concerned about?

 

[widebear]

Hi ,

Is it normal on bigger 2-stroke 2006 that you can feel sort of slight up&down movement on ignition side bearing or is it on its way to wear out ?

Different bearings have different ratings depending on application. If the manufacturer called for a C-4 spec which is for high temperatures they will be very loose to start out with to deal with that heat expansion.There is a very real possibility that some of bearings in our engines are indeed C-4 rated