| Author | Message | ||
     Pkforbes87 |
There's no such thing as a stupid question.. keep that in mind  After the bearings failing in the rear wheel on my 09 XT, I was just trying to think of a way to make them last longer next time. I've heard of people popping the dust seals off the bearings and squeezing more grease in there - not an option for me. I can't imagine that seal ever being the same once pried off a permanently sealed bearing. Anyway.. if I'm not mistaken the hub of the wheel is hollow, but the spokes are not. So what if a person was to drill and tap a hole in the hub, between the spokes somewhere. Then install a grease zerk and fill the hub with grease. This would prevent water intrusion, which in a majority of cases seems to be a contributing factor to the bearing failure. I was thinking marine grease since it's meant to resist breakdown when exposed to moisture. It shouldn't really matter what type of grease because the purpose isn't to lube the bearings - only to keep moisture away from them. The grease would also need to be thick enough to stay in place instead of being slung out of any crevice available. thoughts? | ||
| Hughlysses |
Etennuly did it a little over a year ago: http://www.badweatherbikers.com/cgibin/discus/show .cgi?tpc=142838&post=1403569#POST1403569 AFAIK, it's still working well. | ||
| Pkforbes87 |
Thanks, that answers my question. I think I'll give this a shot after the dealer replaces my bearings and axle. The warranty thing might not go over too well if I show up with holes drilled in the wheel | ||
| Johndeereb |
I just pulled the rear wheel on my 06 uly at 4,500k and the water appears to be entering between the axle and the bearing. This was on the left or rotor side only. The axle showed some rust and the inside of the left swing arm hole before the threads had some gunk like from moisture. It did not appear that the seals leaked but the sliding fit between the axle diameter and the bearing inner diameter would let water enter in this area. Just my 2 cents | ||
| Johnboy777 |
I plan to drill two or three 1/8" holes in the center of the hub over the winter. If water get in, it'll spin right out via the weep holes. I like the grease idea though. . | ||
| Buewulf |
It would take MUCHO grease. That is a big void to fill. | ||
| Hughlysses |
Hopefully Etennuly will chime in. YES, it took a LOT of grease. IIRC, he removed the inner bearing seals before installing them so that the grease in the hub gets forced into the bearings. Give the zerk a shot or two every so often, and you push fresh grease into the bearings and any contamination out. | ||
| Electraglider_1997 |
"I can't imagine that seal ever being the same once pried off a permanently sealed bearing. " If that bearing was permanently sealed then you wouldn't be able to pry out the seal. Heck, the first time I removed the seals was about 25,000 miles ago and I even put holes in them. After finger pushing in grease and reapplying the seals I just followed through by smearing Permatex never-seize over the outside of the seal and my bearings are in primo condition. I do this once per riding season and it has worked fine on my ULY. Used to be standard procedure on Harleys to remove and repack the wheel bearings and those would last forever if taken care of properly. The engine oil is sealed until you unscrew the oil plug. | ||
| Rwcfrank |
I just replaced my tire at 6K miles. I pulled the outer seals and the bearings in my 08 looked great with plenty of grease. Just to be safe I added a touch more grease to the bearings and put the seals back on. I had zero corrosion on my axle but coated it with anti-seize anyway. I torqued the axle to spec and was suprised at how little force is necessary to tighten the axle. My personal opinion is that the rear wheels got overtightened a lot in the beginning and caused some premature failures. As for grease in the hub cavity, centrifugal force and heat is going to cause the grease to find a way out, some way. I am going to go with a bearing regrease every tire change and new bearings at 25k or when they get notchy, which ever comes first. JMHO If you feel that grease in the cavity is the way you want to go fill the cavity with an inert object like a piece of pvc pipe to take up some room. (Message edited by rwcfrank on October 26, 2010) | ||
| Yjsrule |
After having mine go out 500 miles from home, I have a 2010 wheel on order. | ||
| Tootal |
My only question to Vern, and those that have filled that cavity with grease, is what has it done to the balance of the wheel? If you pack it full and the void, which is a casting, is not the same all the way around, will it cause an imbalance? | ||
| Rotorhead |
The grease would act just like dyna beads seeking a natural balance IMO. I've run over 60,000 miles on my original 06 bearings with no issues. I haven't been nice to them either. I do replace tires at least one a year some times 2 so i get to look at the bearings at every swap. I have repacked the bearings once at around 30,000 with no ill effects. I do put a not so thin film of grease on the seals and the entire axle at install. dirt collects around the seals but I have never seen signs of water intrusion. I use the good and tight torque back it off and good and tight again on the axle. i feel allot of the problems with the bearings come from the spacer between the bearings not doing it's part. either a bad torque or a bad spec on the length. | ||
| Pkforbes87 |
From Etennuly's post: "I am doing the experiment with the grease filled hub. I just drilled a hole and tapped it for a grease fitting. Pumped it full of marine grease(the kind used for boat fittings that stay under water). I used to do this on my Honda ATC 200X and 350X's. With all of the traction they would get with those wide grippy tires, and the massive torque loads from the 3.5foot long live axle, I could toast a set of bearings in a day. They were a real PITA to change to just smoke the next set. So I drilled and tapped the hub and filled it up. I pumped in a little more before a ride and right after. Many times after deep water crossings when pumping grease in water would bubble out. I never had to replace the bearings again after I set it up the first time. I was quite pleased after a 1280 mile high speed run to Daytona and back, that I did not have any mess on the back of the bike from escaping grease. I plan to give it a shot of grease when I change tires and will probably do it when ever I do oil changes. It did take four tubes of grease to fill the hub initially. My new bearings are the red seal ones. The black ones were not immediately available when I got mine." The more I read and think about this, the more I like the idea. I think I'll remove the inner seals from the bearings and pack the hub with a good "GC" grease. A couple squirts every oil change should keep any contaminants out as well as keep the bearings themselves full of fresh grease. As for wheel balance, filling an asymmetrical void with grease is only going to add weight to the currently lightweight side. (That's assuming that the hub cavity isn't perfectly symmetrical already) Not saying that it wouldn't be a good idea to rebalance the wheels after doing something like this, but it shouldn't cause any significant changes. | ||
| Tootal |
If you don't fill it full then the grease could move around and possibly balance your wheel but if filled full then it can't do that anymore. Wherever the void is greater you will have more weight there. | ||
| Sekalilgai |
not sure with the grease in the center if the balance would be severely affected.... | ||
| Tootal |
It would amaze you. I balance all kinds of impellers at work. If I forget to put a half key in the key way on the shaft it makes a big difference. DAMHIK! | ||
| Sekalilgai |
haha, I stand corrected! | ||
| Pkforbes87 |
Where the void is greater there will be more grease and more weight added - correct. But that void used to be the lighter part of the wheel. Aluminum mass is heavier than grease mass. | ||
| Johnboy777 |
Mass in the center (of a wheel) is 'less' vulnerable to imbalance, than on the outer edge. Plus, grease also has less mass than alu. It's a moot point, grease-wise . | ||
| Tootal |
I don't believe the point is moot. What I'm saying is that if you fill the void up with grease it would be a good idea to check the balance on the wheel. If the void is larger on one side and you fill it up with grease then it will be heavy there. I agree the closer to the pivot point the less affect it has on balance but it still has an effect. | ||
| Etennuly |
Greg, I believe the balance is of little issue, primarily because the weight of the tire is working it more like a gyro. When you balance a shaft with a small mass such as a light weight pulley on a motor, it would be more sensitive to minor inputs anywhere, including at the center of the axle where it's centrifugal force is of the lesser. I have had no balance issues with it, besides if there was a bit of a gap left in there the grease would spread out to balance itself when the hub warms up. But mine is completely full. I did not pull the inner seals on the new bearings that I installed. I had thought about doing the grease fill prior to replacing the bearings, but didn't decide to actually do it until after the new bearings were snuggly in place. When I replace them again(when ever that may be) I intend to remove the inner seals and drill like three evenly spaced 5/32nds holes in them, then put them back in. It is my belief that if the now limitless amount of grease gets to the inside of the bearings unrestrained, it may warm up and flow enough to leak through the outer seals to make a perpetual mess. My initial intention is to keep water out of the hub with the marine grease. It does that well. I will recommend filling the hub as much grease as possible with a putty knife or other, with the bearing and spacer out of the way, it takes a long time to hand pump four caulking gun size tubes of grease in there!  There is a trace amount of grease that does come on around the outer seal. IMHO this is a good thing. It shows me that the grease, when warmed up to operational temperatures is seeping into and out of the bearing, that means it is getting a fresh supply of lubrication no matter how little, and inspiring confidence that water cannot get in there again. | ||
| Tootal |
What is happening is the bearing is trying to get rid of some grease. Bearings are very smart, they know how much grease they need and if over packed will get rid of what they don't need. An over packed bearing will actually run hot. If I were you I would just leave the seals alone. Use the grease to keep water out but over greasing a bearing is not good either. |
