Novatec 172 rear hub bearing preload problem

bianchiblue

Just bought a set of wheels from the classifieds on here. Wheels have apparently been checked over by the sellers LBS but arrived with the rear bearing preload VERY high - ie the axle turns VERY notchy.

So I look to adjust the preload (17mm cone spanners + 5mm allen key).

However, while the NDS lock nut tightens and preloads fine, the DS lock nut over-preloads the bearing without even being tight, ie with the preload correct, the DS lock nut is loose.

It seems like there is a spacer/washer/seal missing that could fit in between the lock nut and bearing or between the lock nut and axle end (like traditional threaded-axle hubs)?

The only spacer I have is the long tube one, mounted inboard of the freehub body. There is a seal in the freehub at the cassette lockring threads, and then the lock nut. That's it - spacer, freehub with seal, lock nut. Is something missing?

Hub was supplied as Shimano.

As it stands the hub is un-useable as I can only over preload it, ie in order for the lock nut on the DS to be tight enough to stay put, it is advanced to far in on the axle thread, causing too high a preload.

I hopefully await resident Novatec expert Signore Santalucia... (this is my first experience with Novatec!)

arlowood

A quick look at this video might help.

http://www.youtube.com/watch?v=NNUpXfwj ... e=youtu.be

Not sure if the 172 design is the same as the 482 but I think there should be a water seal between the rear of the freehub body and the main inboard shell of the hub itself to keep water from getting at the main bearings.

Is that missing on your set up? If so that could be the problem.

I'm sure Ugo will correct me if that's all a load of sh*t

bianchiblue

Different design. But yeah the hub shell seal is there, but that doesn't affect the "stack length" of the axle from the bearing in the shell to the lock nut.

Basically, upon further inspection the axle bearings feel fine unloaded, but the freehub bearings are shot - tight and very rough

Not sure what the seller's LBS checked over on them but it certainly wasn't the freehub bearings...

ugo.santalucia

They have no preload... you might miss the freehub shim or some other part, or you might have a badly fitted freehub washer (the one that sticks to the flange) or you might have the metal washer in the wrong place... for Shimano it should sit on the NDS (it's a 1 mm thick silver washer).
If you are local I can have a look, otherwise I can't clearly

bianchiblue

Cheers Ugo!

I've searched for a schematic and parts list but can't find anything. What I have from left to right:

NDS lock nut - washer - NDS bearing cap - hub shell with bearings - hub shell DS flange seal - tube spacer on axle between DS hubshell bearing and freehub - freehub assembly with seal in lock ring threads - DS locknut.

The DS locknut inner end mates directly onto the free hub bearing inner race when screwed onto the axle in this setup, therefore tightening the DS locknut does add preload to the freehub bearings.

I'm not local unfortunately but you should be able to see if there's anything missing from the above list... One day I will have a set of your wheels with the little brass washers all round though

bianchiblue

Update - I found a schematic:



I have all those parts.

The problem I have is that when screwing in part #20 by hand, the whole axle becomes very stiff and notchy AS SOON as part #20 comes into contact with the bearing inner race (part #6). So I can't even get Part #20 finger tight as it won't allow the freehub/axe to spin freely.

I am aware that the freehub needs new bearings, but am worried that even if I replace them, part #20 will still contact the bearing race and add preload.

The only things I can think of is that I have to wide a bushing (part #14) OR I need to get this black ring seal/spacer on the cassette body as mine does not have one, only the seal inside the DS flange of the hub shell:



Are A-Type freehubs supposed to have this black ring? If so, that must be my problem! Can't think why anyone would remove it though...

These pics hopefully make things clearer Ugo

Cheers!

arlowood

bianchiblue wrote:

Are A-Type freehubs supposed to have this black ring? If so, that must be my problem! Can't think why anyone would remove it though...

These pics hopefully make things clearer Ugo

Cheers!

The black ring you refer to is the water seal that I mention in my post above and is part 11 in the exploded diagram. I'm pretty sure it would be common to most if not all the Novatec road hub designs. Seems crucial that there should be some form of protection to keep water from accessing the internal hub bearings.

Are you sure it's missing? They can often get stuck onto the inner ratchet ring on the hub body. They are also profiled so you need to make sure that they go on the right way round.

ugo.santalucia

Are you sure the seal is not stuck to the hub shell?
Are you sure you have an A type free hub and not a C type? The C type has an extra needle bearing visible from the inside.
It should work even without the seal, although of course it's not ideal to go around without it

bianchiblue

arlowood - ah, OK, yes I have #11 (as stated previously, the seal inside the hubshell DS flange), I just wondered if the black ring on the pic of the freehub was an additional part that spaced the body out from the DS hub flange. Cheers for clearing that up! :thumbs:

ugo - yep an A-type. No needle bearings, just the regular sealed bearings and spacer as per the diagram.

It must just surely be the freehub bearings are so stiff and notchy they just don't wanna turn smoothly! Strange after only ~500 miles quoted use though. I've had Hope and DT freehub's sealed bearings last many years and many thousands of miles.

arlowood

This might be way off as a possible explanation.

Any chance that your seller or his LBS fitted new hub bearings before he offered it for sale. Reason I ask is that from my own experience of replacing the bearings on a 482 hub (entry towards the bottom of this thread points 9,10 and 11)

viewtopic.php?f=40004&t=12933141

if the drive side bearing has not been fully seated then it will mean that the spacer (part 14) is preventing the free hub from reaching its correct position which would then affect the ability of the lock nut to tighten properly.

Just a thought - could be clutching at straws a bit

desweller

It sounds to me as though the spacer #14 is too short and the freehub is fouling the hub when you lock the assembly together. The axial compression generated by the locknut #20 is ideally taken up along the bearing inner races and the flange in the axle that supports the drive side hub bearing.

But the Novatec hubs are vulnerable to damaged freehub bearings due to the woeful sealing.

ugo.santalucia

Freehub seal (against the flange) fitted the wrong way round? Easy mistake to do....

bianchiblue

arloworld - yes I see your point but DS hubshell bearing is seated properly, clear of the drive teeth.

Des - I see your theory, but interestingly if I fit the freehub without the spacer #14 (for experimental purposes only of course), it all turns freely, but this is due to the freehub bearings not being loaded so they are effectively out of the equation as the races are just spinning on the axle (ie not turning the balls).

ugo - seal is the right way round.

Basically as I said before, it has to be the freehub bearings being so tight and unwilling to turn that as soon as they are loaded they make the axle super tight and very rough and notchy.

The seller is kindly giving me some money towards a new freehub/bearings and I'm pretty sure this will sort it now you guys have cleared up that I have no missing parts.

As Des suggests, I guess the quality of the sealing and bearings in the freehub is a bit lacking as they have apparently only done ~500 miles. I think I will pack the replacement well with grease to help blockade the seals!

I will update once I get the parts!

Cheers again all.

on-yer-bike

The Road parts forum is full of items that are 'as new' or 'only done 500 miles', Ive been conned a few times. Welcome to the crazy world of Novatech. I just bought some new Novatech Campag hubs, the rear of which jammed up when I screwed on the cassette lockring. I had to buy new end caps from Taiwan to make them work. The UK online shop didnt have a clue. The shop you need to talk to is BDop in Taiwan, they are the Novtech experts and sent me the endcaps in 4 days. You may find that you need to change the complete freehub. At least yours are Shimano I think Taiwan and Campag is a risky combo.

bianchiblue

on-yer-bike wrote:

The Road parts forum is full of items that are 'as new' or 'only done 500 miles', Ive been conned a few times. Welcome to the crazy world of Novatech. I just bought some new Novatech Campag hubs, the rear of which jammed up when I screwed on the cassette lockring. I had to buy new end caps from Taiwan to make them work. The UK online shop didnt have a clue. The shop you need to talk to is BDop in Taiwan, they are the Novtech experts and sent me the endcaps in 4 days. You may find that you need to change the complete freehub. At least yours are Shimano I think Taiwan and Campag is a risky combo.

To be fair to the seller, he admitted he knew about the bearings being stiff/notchy, so took them to his LBS for a check over and they said they were just notchy being cheap hubs... not the most thorough LBS! I reckon they just didn't fancy the work for whatever reason :?

Can't see how a lockring could jam a hub unless it was fouling on something - eg too deep a lockring thread contacting the freehub outer bearing? Did you find out what was causing that problem?!

Yep onto BDop for a complete freehub and bearings, which I'm 99% sure will fix the problem. If so I reckon that the hubs are actually pretty decent, upgraded bearings and extra grease in the right places when assembling will see them ending up being excellent hubs I think.

ugo.santalucia

Novatec make some cheap hubs and some excellent hubs... some cheap hubs are pretty decent, like the 172. You will find compatibility issues regardless of how much you spend... Hope campagnolo freehub was a joke, yet, 150 pound for a rear hub.
Personally I have built some 100+ pairs of Novatec hubs and none had problems beside short living bearings in the 482 light model. I am also using Novatec 711/712 hubs myself and they are a superb pair of hubs, considering I paid them 90 quid... they would be superb even if I paid them 300 quid, as I don't see any other similar products on the market being significantly better. Most of the high end stuff (Dt Swiss, Chris King etc.) does exactly the same thing but require tools costing in excess of the hubs themselves to service them, which is an obvious problem.

on-yer-bike

bianchiblue wrote:

on-yer-bike wrote:

Can't see how a lockring could jam a hub unless it was fouling on something - eg too deep a lockring thread contacting the freehub outer bearing? Did you find out what was causing that problem?!
.

The flange round the endcap was too wide so it fouled the lockring and stopped the axle from turning. BDop said there was a bad batch of Campag compatible endcaps. They are fine now its just the wheel that's attached to it that is the problem, but that's another story.

ugo.santalucia

on-yer-bike wrote:

bianchiblue wrote:

on-yer-bike wrote:

Can't see how a lockring could jam a hub unless it was fouling on something - eg too deep a lockring thread contacting the freehub outer bearing? Did you find out what was causing that problem?!
.

The flange round the endcap was too wide so it fouled the lockring and stopped the axle from turning. BDop said there was a bad batch of Campag compatible endcaps. They are fine now its just the wheel that's attached to it that is the problem, but that's another story.

Glad you got that sorted.

Wirral_paul

Wish i'd have seen this earlier - i just removed a Shimano freehub that has been barely used and fitted a Campag freehub to my wheels that Ugo built for me and i have barely used yet.

Did you find the rebuild instructions on BDop's site?

overlord2

In the middle of putting away my stuff for winter I have found that my Planet X 50mm tub freehub is loose and I seem to be having the same problem as the OP.

These have also seen less than 500 miles and I can not tighten up the axle on the cassette side without it fouling and causing the freehub to rachet.

I suspect the bearings maybe shot in the freehub. :x