TM400R Question

[TIKI]

I’m working on a 71 TM400R and on the clutch side there are what appears to be 3 holes filled with epoxy do you know what these are for? I want to heat the case to remove the crank bearing but don’t want to damage anything.. Thanks

[brent j]

Check the OD of the bearing. It's possible that a previous owner drilled those holes to remove the bearing.
I've seen a main bearing collapse and become difficult to remove with just the outer race

Or if the holes are outside the bearing then I have NFI

[djr]

I am currently rebuilding a Yam 1974 DT250 engine, it also has these 3 holes filled with some epoxy around one of the main bearings.
I think I remember my Suzuki RL250 engine having the same thing as well , I guess they are used maybe in the manufacturing process and then filled in after ?
I heated the cases up on the RL250 engine and changed the main bearings without any problems regarding these holes.
I am sure its not a problem, if the epoxy isn't loose or anything .
I expect someone on here knows their  exact purpose
hope this is helpful

[sleepy]

The holes are there from the casting process. They are used to hold the iron sleeve in place as the alloy is cast.
There is no real benifit in heating that type of case to remove bearings as the expansion rate of the iron sleeve is the same as the bearing, just press them out and in.
If the epoxy has been damaged just re-do it.

[shelpi]

heat the case, ice the bearing, ive had some then just fall out (not all)
reverse   nice oven fresh cases then add cool to room temp (in winter) bearing
garnish with beer or wine

[sleepy]

heat the case, ice the bearing, ive had some then just fall out (not all)
reverse   nice oven fresh cases then add cool to room temp (in winter) bearing
garnish with beer or wine

This method does work well with cases that don't have an iron sleeve cast in as the difference in expansion rates are great. Also they have a much larger interference fit when the bearings go straight into alloy.

[shelpi]

heat the case, ice the bearing, ive had some then just fall out (not all)
reverse   nice oven fresh cases then add cool to room temp (in winter) bearing
garnish with beer or wine

This method does work well with cases that don't have an iron sleeve cast in as the difference in expansion rates are great. Also they have a much larger interference fit when the bearings go straight into alloy.

Yep its not a sure fire rule, and yes i have various driff's for knocking in or out, if I cant get it in the press,
but if we can get what ever in the press with a squirt of yeild is the way togo!
but mr heat and mr shrink still have there role to play