Gap between frame and rear wheel fork

[Angry_Bill]

Good evening ladies and gents.  I'm putting the transmission back in after repair and I'm addressing an old problem that I noticed while riding the R65 back in the day before the pawl spring broke.  I thought the gap between the frame and rear fork was excessive while riding, causing the rear wheel to drit back and fourth slightly, which was noticeable.  Now that I've got the rear fork loose in the frame, I measure almist 3/16" gap!  that seems excessive.  I notice from the microfiche parts list that a spacer was used up to 1980, however, my bike is a complete 1982.


Below is a shot of the 3/16" gap, with the rear fork being held under no tension from the main hex nuts.



I'm must certainly going to install a spacer washer unless someone in the audience can convince me otherwise.  Thoughts ARE greatly appreciated.  Thanks !  Bill

[Rob Valdez 79 R65]

Do not install a spacer.  The early bikes had them, the later ones did not.

3/16" is not excessive.  

The bearings are providing the support needed, the gap is irrelevant.


Your primary concern is that the drive shaft is not rubbing on the inside of the swingarm.

Secondary concern is that the swingarm is centered in the frame.
To do that, just make the gap equal on both sides.  Do not be concerned about the size of the gap, unless your frame has suffered MAJOR trauma.

[Justin B.]

General practice is to adjust the swingarm bearings until you have an equal gap on both sides.  This will put the swingarm in the middle and should also keep the the driveshaft yoke out of trouble.

[Angry_Bill]

Thanks Justin and Rob.  No spacers it is.  I'll read up on how to adjust the bearings to obtain equal spacing.  I believe the spacing was always somewhat or all off center in the past.   Bill.

[nhmaf]

Yes, unless othe frame has had a mishap, the gap should be roughly equal on either side.  The key factor is to make sure that the pivot pins and bearings are properly installed and preloaded.   Too much preload and you'll wear out the bearings quickly.  Too little and you'll feel like the rear end isn't quite attached to the rest of the bike !

I measure the gap on either side before taking it apart and make a note of the measurements, so when it all goes back together I try to set it up the very same way.

[Semper Gumby]

We have been here before.  I use a 4mm allen to center the swing arm.  Let see where is that post.....

See Reply #10  Spline Lube Job

Rob how do I get the link for this?

[Bob_Roller]

Just a little tidbit of information, regarding the bearings.

If you have a 'needle' fitting on a grease-gun, you can pump a little grease through the bearings, by inserting the needle fitting into the hole for the allen wrench.

I always put a little grease in there after I wash the bike (twice a year, whether it needs it or not !!!).

[Justin B.]

I would suggest a bit more than "a little" grease!  I pump the crap out of it until a good bit of the old grease is expelled.

[Rob Valdez 79 R65]

Just a little tidbit of information, regarding the bearings.
If you have a 'needle' fitting on a grease-gun, you can pump a little grease through the bearings, by inserting the needle fitting into the hole for the allen wrench.
I always put a little grease in there after I wash the bike (twice a year, whether it needs it or not !!!).

'needle' fitting may be a little misleading.  For this application, I like a larger tapered fitting (usually has a nylon tip) like this one.



http://www.hardwareworld.com/05-041-Seal-Off-Dispenser-pRNHCGY.aspx


If you are replacing ANY roller bearing with new, it is a good idea to manually pack it with grease before you install it, anyway.

[Justin B.]

I got a nice rubber tipped one like your picture at Pep Boys several years ago.  It works much better than the metal BMW item...

[Bob_Roller]

Just a little tidbit of information, regarding the bearings.
If you have a 'needle' fitting on a grease-gun, you can pump a little grease through the bearings, by inserting the needle fitting into the hole for the allen wrench.
I always put a little grease in there after I wash the bike (twice a year, whether it needs it or not !!!).

'needle' fitting may be a little misleading.  For this application, I like a larger tapered fitting (usually has a nylon tip) like this one.



http://www.hardwareworld.com/05-041-Seal-Off-Dispenser-pRNHCGY.aspx


If you are replacing ANY roller bearing with new, it is a good idea to manually pack it with grease before you install it, anyway.

Needle fitting wasn't the best description for the tool , just trying to get across that it wasn't your typical grease zerk fitting.

Also I didn't know if this was a bit of info that was widely known , I have mentioned it to a few BMW riders, and several didn't know about it.

[Rob Valdez 79 R65]

I have seen plenty of the needle-type fittings while shopping for the larger, plastic-tipped one.  I can see where they would be handy for something, but I have never bought one.