Aghhhhhhh! Freehub not working!!!

[Maz]

Got about a mile into my commute this morning then gave up and walked home.

No power at all when pedalling, so had no other option! Wheel has been playing up recently, I guess the extra cold this morning exacerbated the problem.

Is there some way I can 'service' the freehub (lube? wd40?) just to free up the springs/pawls (assuming that they are the problem) and keep it going a bit longer? Wheel is a Shimano R500.

Many thanks

 

[amaferanga]

You mean you turn the pedals, but the cassette doesn't turn? If so then you could take the freehub off (a bit of Googling should shed some light on how to do that for your model of hub) and give the pawls a good clean and and regrease with some suitable grease.

 

[Globalti]

The grease has stiffened up and the pawls are stuck. If you can't afford a new cassette try flooding it with WD40. If that works, follow it up with some light oil (3 in 1) and let the WD40 evaporate leaving the oil behind.

 

[Maz]

You mean you turn the pedals, but the cassette doesn't turn? If so then you could take the freehub off (a bit of Googling should shed some light on how to do that for your model of hub) and give the pawls a good clean and and regrease with some suitable grease.

No, the cassette is turning round. Just no drive.

 

[compo]

If the cause is, as suggested above, thickened grease trapping the pawls could you as an emergency measure warm up the freehub to thin out the grease and release the pawls or are there seals and things that would get damaged. Not much help stuck on the side of the road I know, but I was just wondering.

(I have never dismantled a freehub, but when I looked at my Shimano one I couldn't see how you would get inside it anyway).

 

[accountantpete]

Basically the pawls fold down on top of a spring when you coast. When you pedal forward the action allows them to spring up and engage the hub.

What has happened is that the pawls have stuck in the folded position because the grease/grime is stronger than the spring.

So you need to wash away some of the grease/grime by flooding the freehub at the point where the freehub meets the hub just beyond the biggest sprocket.

 

[fossyant]

The cold weather will cetainly show problems up. I've lost drive in a freehub in the cold, got home and in the time I'd gone off to get changed to 'drive in', it had thawed. New freehub ordered.

You need to undo the cones, remove the bearings and get a 10mm allen key in the drive side and remove the freehub. Remove grease from the bearing surface, then run oil through the freehub, as suggested, leave to drip, then re-grease bearing surface and re-assemble

 

[amaferanga]

No, the cassette is turning round. Just no drive.

That's what I meant, I just didn't phrase it right.

 

[Maz]

The cold weather will cetainly show problems up. I've lost drive in a freehub in the cold, got home and in the time I'd gone off to get changed to 'drive in', it had thawed.

Yep! Same thing happened to me!

 

[Maz]

OK, well I got it working again using accountantpete's method. Fingers' crossed for tomorrow.
Thanks, all.

 

[fossyant]

Make sure you do give the hub a service though.

Did it freeze today ?

 

[PpPete]

The traditional method of unfreezing old school freewheels on the road .... I don't know if it works with freehubs.

Piss on them.

 

[fossyant]

The traditional method of unfreezing old school freewheels on the road .... I don't know if it works with freehubs.

**** on them.

It should do !

 

[Maz]

Make sure you do give the hub a service though.

Did it freeze today ?

The freehub was OK today, thanks (it was much colder this morning too)
I couldn't service the freehub last night because I couldn't get the cassette off, because the oil filter chain wrench I used broke.
What I did was drench the area between largest cassette ring and wheel with WD40 and then thin oil.

 

[Globalti]

Be careful with that Maz, you could be driving grit into the freehub. Better to try to get that cassette off, remove the freehub and clean everything up before drenching it with light oil.

Now I think about it I reckon water could have been the problem. When you turn the pedals backwards, does the hub rotate freely or does it drag and the chain sag on its top run?