123123user

I cleaned two bikes today and noticed one bike's (especially) rear wheel spin ends much quicker than the other.

​​​​​To compare, I set both at the hardest gear and pedaled a quarter turn. The other bike's wheel would spin for more than a minute uninterrupted and the subject bike hardly clears 10 seconds. I could pedal both as hard as I can, and you'd be surprised how quick its spin ends.

I checked my friend's bike too and his rear wheel also spins for quite some time.

The bike in question was fresh from a full wash and no clicking noises coming from it either. The brakes and wheel are pretty aligned. There doesnt seem to be anything stopping it -- the stop seems to be organic and natural but still, unnaturally short.

jadmt

disc brakes? if so could be dragging even if you don't realize it.

Chuck M 

The absence of clicking does not rule out bearings or lube. So that is what I would naturally suspect first. Can you loosen the rear wheel and see if that makes a difference? Your bearings may need adjusting and when the wheel is tightened in the dropout, it binds. Also is this a QR, through axel or nutted axel?

123123user

Both are quick release hubs

I check the brakes quite a lot, the rim brakes dont touch any surface of the wheel

Chuck M 

Loosen the QR then and see if it makes a difference. If the bearings need adjusted, lube them too while you are at it.

genejockey 

Tight or worn bearings? I got a wheelset from a guy on Craigs List that was like you describe - maybe why he sold them. The bearing preload ring was too tight. Once properly adjusted, they spin great. It's easy if you know how, but if you don't, I'd ask a bike store. One way to test is to take the wheel out of the dropouts, hold it by the ends of the axle (not the QR or through axle), and spin it and see if it still does the same.

79pmooney

Spin the cassettes (freewheels) of both wheels and compare. One may have neglected bearings in it. Next is to lift the rear wheel and spin both bike's tires backwards (when the cassettes will be locked to the hub and not a factor. If the two wheels are different, this may be a hub bearing issue. Some wheels have tight bearing seals when new. This makes little difference when riding but quite a bit when it is just the lightweight wheel spinning.

msu2001la

I have a Zipp rear hub that has a little rubber dust seal that covers the bearings. If it's not pushed in correctly on the freehub shell (it has little grooves and requires using a small screwdriver to physically push the seal into the groove) it'll cause freehub drag like what is being described.

It drove me nuts for a little while until I finally figured it out.

msu2001la

You mention washing the bike, so I've gotta ask, was high pressure involved?

wheelreason

Of course, to get all the Simple Green off...

Troul 

did you polish the axle prior to spin testing?

urbanknight

Since you ruled out the brakes, I would suspect the bearings or too tight of quick release next. Are the bearings cup and cone or cartridge?

rsbob 

Satan messes with bearings all the time. It’s a medical fact.

123123user

Never taken a look at it, but according to the spec sheet of WH RS100 it is cup and cone

Tried spinning with the QR locks loose. Still the same short spin time.

majmt 

If there is no clicking, you might need to check if the pawls, springs, and/or ratchet teeth in the free-hub (freewheel) are gunked up with old lube. Could need cleaning or replacing. Dribbling in some penetrating oil might be a quick and dirty way to loosen things up.

123123user

I headed to the LBS. Mechanic did not check the internals but said this was on the hub (WH-RS100) and would be the same even after regreasing. I'm doubtful but I did try spinning one of the bike's wheels hanging on their workshop and the spin ended pretty quickly too.

indyfabz

My rear hub is all engorged and tingling.

Iride01 

It might be nothing. The forces of a 180 lbs or more bike + rider moving the bike on those wheels are totally different than the forces on those very light wheels spinning in air.

The wattage penalty is probably very low and not significant compared to anything else we talk about.

However that's not to say that you shouldn't check if something is wrong. But even a freshly greased wheel will sometimes slow quicker as it takes some time for the excess grease to be pushed out of the way of the bearings. And if one crams grease into every possible place grease can be in the hub as I use to, then it can take a while for all that excess grease to be moved out of the way.

JohnDThompson 

All else equal, the ratchet mechanism in the rear hub means it will spin down sooner than a front hub. You've ruled out brake drag, I see. Next, check the bearings. Remove the wheel from the frame and see if the axle turns freely and smoothly. If not, you should clean and repack or replace the bearings. If it is smooth, no worries. Unloaded wheel spin time does not reflect performance when under load.

urbanknight

It's true. Any time I wonder if something is dragging on my bike, I notice how I have no trouble keeping up with my riding buddies on the downhill... only on the uphill.


One way to check that: take the chain off and see if the wheel spins longer. If it does, that should definitely not be a concern since it's only dragging when you're not trying to propel yourself forward, and as Iride mentioned above, it's probably a miniscule amount in the grand scheme of things.

urbanknight

I don't know if it's truly a good idea or not, but a more experienced mechanic once told me to set cup and cone bearings as loose as possible within the acceptable range so that the skewer tightening on them doesn't make it too tight. But as mentioned elsewhere in this thread, a wheel coming to a stop after a few seconds while spinning free does not necessarily indicate a significant amount of drag, and I think my rear wheels have always stopped sooner than the fronts.

zandoval 

Pressure washing can blast the grease right out of your bearings. Other times the soap in your wash can emulsify grease causing one part of the grease compound to precipitate out. I used to use white lithium grease and after using an ammonia based soap (Scrub Bubbles), it would harden in the bearings.

That problem was solved when I went to Generic Marine Grease. I would suggest doing a detailed service on your bearing just to check it out.

Now days when I wash my bikes I do a generous lubrication of all parts and then use a soapy brush to scrub off the dirt and debris. I no long pressure wash unless I am going to re-service all my bearings.

Russ Roth

Just pull the wheel off and spin the axle by hand, don't spin the wheel in your hand, just the axle. If it feels like there's any resistance, adjust the cones. Ideally you want a pair of 15mm cone wrenches and a pair of 17mm wrenches. I usually start by tightening the cones against their respective lock nuts, you're liable to find one of them moves more than the other. Then I use the 15mm cones and I start twisting the cones away from each other which also tightens them further against the lock nuts, after every 1/8 turn I give the axle a spin and a shake to see if its moving smoothly and cleanly but isn't so loose it can wiggle. If you start to feel any kind of wiggle use the 17mm to tighten the axle buts towards each other, should probably only take a single 1/8 turn to have them spinning perfect. Leaving the situation will pit the cones and prematurely wear out the hubs so don't assume its good enough. If it isn't the axle you can drip a tough of triflow into the freehub body but this requires removing the cassette so you can see the line between the cup in the freehub and the outer shell of the freehub, you can drip on triflow into that seam and hand turn the freehub body to help it migrate in, it'll help otherwise you'll have to probably replace the freehub body if it has too much resistance.