Rebuild Questions

[DieHard2Smoke]

Upon tearing down my 85 i found some play on the stator, is the bearing junk and/or should I take out the crank to be inspected?

I just squeezed the rings on the exhaust side of the piston.

rod still felt tight and clutch side bearing still felt tight. on a positive note, one of the previous owners had a port job done and cleaned up the casting flaws. was pretty obvious when i pulled off the jug.

[100hp honda]

bearing shot. chances are its been like that for some time but its best to replace them before the cage comes apart which has been known to happen. full rebuild is your best bet. get your wallet ready

this aint a honda crank bearing but same thing just smaller size. pretty much like whats behind the clutch basket. bearing to the right is the upgrade roller style. converted my ktm and im wondering if theres one to fit the honda . might be one for the countershaft at the front sprocket as well. anyone happen to know the bearing sizes behind the basket and front sprocket ? would be a killer upgrade if theres something that fits

[dogger315]

the bearing sizes behind the basket and front sprocket ?

25X52X15 mainshaft (behind the clutch) and 24X56X14 countershaft.
Let me know if you find a match.

dogger

[100hp honda]

shows one for the mainshaft. NUP 205 or NJ 205 might work. more or less just like in the picture just slightly different size. not finding anything for the countershaft

[Rosco-Peeko]

Not sure that would be wise. A roller bearing will only accept radial loading. A ball or thrust bearing accepts raiding and axial loading to a degree. In short its better to have some than none. If if you are lucky with the roller--be prepared for expedited wear. Worst case, you side load the hell out of a roller bearing which result in your bottom end tearing itself up.

Tech Geek time, jet engine work, we put thrust (ball) bearings between rotating assemblies that move or shift slightly (radially and axially) during operation. On assemblies that are only subjected to radial (up and down) loads we use roller bearings.

Sure you could probably sidle a ball bearing (thrust) in where a roller would normally be. However, it would be wasteful due to design certain assemblies do not move enough axially to warrant the use of one.

Now if you were employ a simple standard roller where a a thrust bearing belongs. Well that would be a gamble on an engine that the Low Pressure Turbine (N1) is at 7K RPM and the Core (N2) is at 10K RPM....those are both idle readings off an F110-129. You'll kill someone due to the motor coming apart.

Just food for thought...do what ya want. I know the CR500 mill is not a Afterburning Jet Engine...close but.. The correlation is still there on what bearing to use where. I have hear some manufactures use rollers as crank bearings...they have done the R&D. Id use what Honda recommends.