Sunday, May 6, 2012

Endplay.....

All you guys who check the endplay on brand new wheels, raise your dial indicators.....I thought so. How many guys just look at the little tag that they put on new wheels, see .005, and say "OK"?....I thought so. How many guys check the endplay on used wheels....I thought so.

I check the endplay on every wheel I put on a bike. I've seen those little tags they put on the spokes. Evidently 11 yr. old Chinese kids can't read a dial indicator. I've seen tags that said ".017", and had "0" endplay when checked, and I've seen tags say ".004", and have had ".030". Too tight an endplay on a Timkin tapered wheel bearing will toast it on the road, and most likely seize them to your axle just for good measure. Too much endplay, and you'll be wondering why your bike is shimming like a hula girl when you're passing that semi at 80 mph. Wheel bearing endplay is pretty fucking important!

While I had this particular 18x2.15 wheel built by Woody's Wheel works, the hub is aftermarket. Woody's always does a fantastic job on the wheel, but I always check the endplay regardless. I do it by clamping the axle in the vise, stacking some spacers on each side of the hub, and torquing the axle nut to 50 lbs/ft. Then, I set my magnetic base and dial indicator up, make sure the wheel is settled on the lower bearing, set the pointer on the center of the axle, and then I pull straight up on the wheel. Lots easier than trying to do this on the bike like H-D shows you in the manuals, especially if you have to shim and check it several times.

Not good this time - .026 endplay, waaaay over spec. By the time that .026 gets out to your wheel rim, that is about a 1/16" of movement of that wheel. Harley says anything from .004-.018 is good, I try and keep it right at around.003, because when you pack your bearings, you'll get a little more additional endplay to your dry bearing measurement when you're finished. You are checking the endplay with dry bearings.....right?

So, no big deal...I just take the inner spacer out, shorten it a little, and check it again until it come into spec. Wrong. Seems Uncle Chu decided to make the little rings that center the axle spacer in the hub (so it makes it easier to slide the axle through) bigger than the ID of the bearing race. To get the spacer out, I have to pull a bearing race out. Fuck that! Out comes the welder, a bead around the race, and it's out. Before I shorten the inner spacer, I take and turn down the centering rings until I can slide it out through the bearing races, like H-D does theirs. This way, the next guy that puts in the bearings and races when they're needed next time won't have to go through all this shit.

I shorten the inner spacer, put in a new race, assemble the wheel, put it back on the axle, and presto - only 1 1/2 hours later, I have .003 endplay on the bearings. Back apart again to pack the bearings, and install the wheel. Was it worth the work? Well, I could have just said fuck it when I saw the initial endplay, fuck it again when I saw the spacer wouldn't come out....but that's not how we do things around here, not by a long shot. Some guy is going to be riding this bike.......

3 comments:

WhitelinePsycho said...

Tiny numbers can mean big drama, great article mate, especially as I'm about to get some new hoops laced up, thanks a mess mate.

DJ said...

Every wheel every time! When we get a different bike in the stable thats one of the first things I check. My HD manual says .002-.006" and I like .003 too but will usually let .004" go. Great write up, I know to many guys that let it go because it's a pain or it takes time to do it right.

Greg said...

Man, I can learn a lot from you. Keep up the good work.