mainshaft end play 1986 FLTC

[ChuckB]

Took my 5 speed out of the frame to deal with the pivot shaft being frozen in the case. I resolved that issue and decided to replace all the bearings while it was out. The bike has over 100K miles on it. I checked the mainshaft for end play before disassembly and found it to be unacceptable.. the book calls for zero end play. Went online and bought the bearings. Replace them all, including the two trap door bearings. When I got it back together, the mainshaft still had end play. The bearings I used for the trap door were mfg'd by F.A.G. P/N: 6204 C3 . Made in Korea. The play is coming from the bearing. I used the correct tool to install them to eliminate cross stress.

Are these bearings junk? Should I order some different ones? OR not worry about it??

[mark p]

Originally Posted by ChuckB

Took my 5 speed out of the frame to deal with the pivot shaft being frozen in the case. I resolved that issue and decided to replace all the bearings while it was out. The bike has over 100K miles on it. I checked the mainshaft for end play before disassembly and found it to be unacceptable.. the book calls for zero end play. Went online and bought the bearings. Replace them all, including the two trap door bearings. When I got it back together, the mainshaft still had end play. The bearings I used for the trap door were mfg'd by F.A.G. P/N: 6204 C3 . Made in Korea. The play is coming from the bearing. I used the correct tool to install them to eliminate cross stress.

Are these bearings junk? Should I order some different ones? OR not worry about it??

We noticed a lot of that with the *** bearings at the shop as well. We switched to NSK just for that reason.

[ChuckB]

Originally Posted by mark p

We noticed a lot of that with the *** bearings at the shop as well. We switched to NSK just for that reason.

Went back to ebay and bought the NSK's. They came in today and I was surprised that they were made in USA.

Tried to get the other ebay seller to honor his 15 day return explaining the poor quality of the bearings and he said:

No, you may check with your local Harley davidson dealer.
Thanks

I guess the quality wasn't his fault.. I did call him a jackass though!

[ChuckB]

Same thing with the NSK's.. play.. I give up.. I am running them and see what happens..

[mark p]

Are you sure it is the door bearings where the play is coming from and not the case bearing?

[High Torque]

Are the bearing dry? They have a tolerance when ground to accept a film of oil. How much end play do you have?

[Dan89FLSTC]

Originally Posted by mark p

Are you sure it is the door bearings where the play is coming from and not the case bearing?

The ball bearing in the trap door is the bearing that holds axial position of the mainshaft, the other end of the mainshaft is supported by needle bearings, which support it radially.

The case bearing does not affect the axial position of the Mainshaft.

All shafts that have their run position set by ball bearings have some axial play in them. I know the service manual says no end play, but that is not realistic. If the shafts had no end play, it would mean the bearing was too tight.

[ChuckB]

Originally Posted by mark p

Are you sure it is the door bearings where the play is coming from and not the case bearing?

Must not have been. I think you're right.. read my next post..

[ChuckB]

I assembled the tranny and put it in the frame not quite satisified with the mainshaft play on the second set of trap door bearings.. torqued down the final drive gear nut up against the sprocket and guess what? ZERO mainshaft endplay.. I can't imagine why it made a diff.. I am a rookie though.. I can only guess to check for endplay on a fully installed tranny, right?? Maybe the first set of bearing would have been okay (?) Thank yall for you input.. now tell me what I did wrong

[ChuckB]

Originally Posted by High Torque

Are the bearing dry? They have a tolerance when ground to accept a film of oil. How much end play do you have?

Wet with gear oil.. never measured the endplay, but it was a lot.. I could grab the shaft it really slid it in and out quite a bit.... posted out of order.. read above.. I currently have no endplay. Thanks!

[ChuckB]

Originally Posted by Dan89FLSTC

The ball bearing in the trap door is the bearing that holds axial position of the mainshaft, the other end of the mainshaft is supported by needle bearings, which support it radially.

The case bearing does not affect the axial position of the Mainshaft.

All shafts that have their run position set by ball bearings have some axial play in them. I know the service manual says no end play, but that is not realistic. If the shafts had no end play, it would mean the bearing was too tight.

yep.. hear what you're saying.. I know I am replying out of order, but I think i have it figured out, but am still confused. Thanks!

[mark p]

Once the clutch is in place and torqued the mainshaft can only move as far as the next pair of gears. You have to think of it as a complete gear set and not as a shaft by itself. Although your mainshaft rides on bearings inside the main drive gear it can only move as far as the second gear pair will allow it, then the 4th and the 3rd and so on. Although the gear pairs are separate from the shafts the are held in place by retaining rings and thrust washers so movement that you see in a complete unit could be coming from either side of the case. I'm getting far to in depth now but I hope you get the picture.