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Hub question from complete novice
#1
I'll preface this by saying I know very little about bike maintenance.

I recently bought a new bike, Vilano's generic, entry level 21 speed. I'd hoped to find a good deal on a used bike on Craigslist, but quickly realized I didn't have the bike knowledge to do that. The Vilano had good reviews for my price range, but I realize that, to an extent, you get what you pay for, too.

I got the bike yesterday and started to do some prep maintenance. I know I could've had a bike shop do everything for a reasonable price, but I like figuring stuff out and doing my own maintenance.

Based on reviews of the bike, the first thing I adjusted was the front wheel hub. Before adjustment, things seemed a bit tight. I'm confident I've got the adjustment dialed to the point where it's juuuust tight enough to eliminate any lateral movement in the axle, but no tighter than that. The inside of the hub looked pre-greased, but I added some Park Tool PolyLube 1000 in for good measure. After adjustment, I can still feel a bit of grinding when I turn the axle by hand, like I can feel the bearings against the cones. When I put the wheel back in the bike and spin it, it seems to rotate just fine (spins forever, no audible grinding), but that bit of friction I can feel when turning the axle by hand is bothering me. I'm not sure how to label the feel. It is a sort of resistance, but that seems an imperfect description, since it doesn't noticeably hinder the spin of the wheel.

I popped the front wheel off my roommate's nicer bike to compare, and his axle rotates completely smoothly when I turn it by hand. I can't tell any difference when I spin the wheels in the frames--just by feel in hand. I proceeded to adjust my back hub (without adding grease, just in case that was what I screwed up), but I'm getting the same SLIGHT grinding feel when I turn the axle by hand.

Is this just the result of inferior wheels? Is it okay to feel that slight resistance? Am I screwing something else up? The way the wheel spins fine in the frame leads me to believe that the wheels would be fine to ride on, but my perfectionism (paired with my jealousy at how smooth my roommate's wheel felt), has me a bit concerned with the way I can feel the bearings when I turn the axle by hand.

Thanks in advance for any help/advice/wisdom.
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#2
First of all NEVER mix greases or oils; this applies to bikes, cars and everything else.  Without knowing the chemistry of each, you do not know if the mixture will be a lubricant or a glue.  The only people that I know who had an engine failure could trace the failure to adding a different oil to the engine.

I strongly recommend cleaning the mixed grease out of the front hub, use paper towel to get most, then q-tips, finally tooth brush and isopropyl alcohol.  Clean the cups (in the hub), cones (one the axles) and the balls.

Pick your grease, if you want to continue spending the $$$ for the Park stuff, no problem, it is your money.  I use boat trailer wheel bearing grease; it is very water resistant.

Pack the cups full of grease, install the bearings, put more grease on top, assemble, then wipe off the excess.

Regarding the roughness of the bearings - yes low end wheels that have not been run in yet.  You will need to re-adjust the wheel bearings in about 100 miles have they have worn in: the cups and cones will get a polished wear track.  Then, they'll be good for a few thousand miles if you clean and regrease once per year.  Sometime after 5K miles, the rear wheel cups will start to pit, things will get noisy.  You can keep riding it, as the noise level increases.  Eventually the front cups will also pit.  The cups are not replaceable.  Cones are replaceable, but rarely are in an issue because they are comparatively thick, and we supported by the steel axle.  Cups are pressed into the aluminum hub.

The bikes I build for my own riding have cartridge bearing hubs.  Wheelmaster offers some inexpensive ones, but only in 135mm O.L.D.  For my Trek 620 project (130mm O.L.D.); I have a set of Velocity hubs with cartridge bearings.  Cartridge bearing hubs have no adjustment.  The best are Phil Wood - one of his rear hubs costs as much as your bike.
Nigel
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#3
This is a interesting topic. I too have turned axels by hand and can feel a little roughness. However when you put the wheel in a bike stand the bearings are smooth as silk. I thought this rough effect, while turning by hand with no weight on the axel, may have been caused by the gap in the wheel bearings (1/2 a ball is it?) and the axel had not set the wheel bearings into their proper position?
"Where ever we go, there we are"
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#4
the roughness you feel is the surface finish (roughness) of the cup and cone as the very very smooth balls roll over the imperfections.

On more expensive hubs, there is more time ($$) spent polishing the cups and cones; resulting in less roughness, to the point where a human can't feel it.

Cartridge bearings have the advantage here because they are made in such high volume for industrial applications, they are better polished because of other customers' requirements.  For example, Seagate makes more disk drives in a couple days than the whole bike industry makes bikes in a year.  Industrial companies drive the requirements, bicycles benefit.  Cup and cones are solely for bikes, and there are many different ones, all made by smaller machine shops, without the $$$$$$$ tooling to do the processing super fast.
Nigel
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#5
Thanks for the help, guys.

Common sense probably should've told me not to mix the greases. I will clean that front hub out and re-grease. Luckily I left the factory grease alone in the rear hub. I wasn't even aware that the grease I bought was expensive, and only mentioned the name in case it was the wrong kind of grease to be using (which, technically, it was since I was mixing it--but I digress). I found the grease by typing "bike grease" into Amazon. Sounds like I can find something cheaper after this tube runs out.

I'm relieved to hear that the roughness in my bearings should just be a matter of breaking them in. You've eased my mind considerably. Also good to know that I should re-adjust after about a hundred miles.

This is definitely a beginner bike, but if I find myself enjoying it and wanting better gear, my first upgrade will probably be to throw some new wheels on this thing. At that point, I'll have to take a better look at cup & cone vs. cartridge bearings and the like.

Thanks again for your help. Wish me luck with the rest of it. I spent about 30 minutes figuring out how to pump up a Presta valve last night, so I may be back for more advice.
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#6
I remember my first experience with Presta valves..... I even drilled the original rims on our tandem out for Schrader valves, since then I have become a convert to Presta.

If you have the $$$; Velocity has some nice wheels.  

I build my own wheels, as noted above.  I have tried Sun, Alex and Velocity rims.  Velocity are my favorites, easy to build because they are flat and round.  Sun are the worst of the three.  Alex rims are generally pretty good.  I built my own truing stand: http://forums.bicycletutor.com/thread-3192.html
Nigel
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