Similiar I take them out take out the seals degrease and repack with a decent grease. It is annoying though that one of the BB pivot bearing has totaly failed after 7 ish months. Imagine that kind of quality bearing somewhere on your car.
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 Similiar I take them out take out the seals degrease and repack with a decent grease. It is annoying though that one of the BB pivot bearing has totaly failed after 7 ish months. Imagine that kind of quality bearing somewhere on your car.
Aye...that would indeed be a pain in the arse..7 months on a bearing from a new frame is warranty material mate.
Quick e-mail to specialized will get an answer. I gotta applaud specialized warranties..they have been great in the past for me.
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 Thats one reason why I thought I might try the steel shielded ones as they are for "Agricultural use"
IIRC the steel shield is to protect the rubber seal from being damaged by some hamfisted farmhand/mechanic. Water grit etc will still find its way in.
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You just spurred me to send an e-mail to specialized over my collapsed ti-railed alias saddle that bent in the nov of 2007 and has lain lost in my house for over a year.
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 Didnt realise stainless bearings were more ressitant to the abrasive paste that develops. Surely the seals are identical. So we are just putting a more resitant bearing in so it doesnt grind to a halt/sieze
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Stainless will be a little more resistant but the outer surface will wear more then. I think you have more time to 'catch' stainless bearings and clean them up compared to mild steel ones. Didn't Marin claim to use some sort of bearing that was designed to be used in limited movement applications on the Quad, came from the aileron of an aircraft IIRC. They had a lifetime warranty on them.
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 its rust as much as grit and mud that kills bearings as Mike says with stainless you get more time to "catch it" if that kind of maintainance is your bag.
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 Bearings are like a few other things on MTBs,they were just not made for the purpose they're used for as there are no alternatives so expect problems like this.
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I'm just in the process of registering with SKF to gain access to their technical area Watch this space 
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Well this is abit compliacatedid The bearing size should be selected on the basis of static load ratings C0 instead of on bearing life when one of the following conditions exist: – The bearing is stationary and is subjected to continuous or intermittent (shock) loads. – The bearing makes slow oscillating or alignment movements under load. – The bearing rotates under load at very slow speed (n<10 r/min) and is only required to have a short life (the life equation in this case, for a given equivalent load P would give such a low requisite basic dynamic load rating C, that the bearing selected on a life basis would be seriously overloaded in service). – The bearing rotates and, in addition to the normal operating loads, has to sustain heavy shock loads.
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In all these cases, the permissible load for a bearing is determined not by material fatigue but by the amount of permanent deformation to the raceway caused by the load. Loads acting on a stationary bearing, or one which is slowly oscillating, as well as shock loads on a rotating bearing, can produce flattened areas on the rolling elements and indentations in the raceways. The indentations may be irregularly spaced around the raceway, or may be evenly spaced at positions corresponding to the spacing of the rolling elements. If the load acts for several revolutions the deformation will be evenly distributed over the whole raceway. Permanent deformations in the bearing can lead to vibration in the bearing, noisy operation and increased friction. It is also possible that the internal clearance will increase or the character of the fits may be changed. The extent to which these changes are detrimental to bearing performance depends on the demands placed on the bearing in a particular application. It is therefore necessary to make sure that permanent deformations do not occur, or occur to a very limited extent only, by selecting a bearing with sufficiently high static load carrying capacity, if one of the following demands has to be satisfied – high reliability – quiet running (e.g. for electric motors) – vibration-free operation (e.g. for machine tools) – constant bearing frictional moment (e.g. for measuring apparatus and test equipment) – low starting friction under load (e.g. for cranes). When determining bearing size based on the static load carrying capacity a given safety factor s0 which represents the relationship between the basic static load rating C0 and the equivalent static bearing load P0 is used to calculate the requisite basic static load rating
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Is it really........
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 The main problem with shock pivot bearings is that they move through such a tiny range of motion that any water in there is gonna seize them solid, totally irrespective of the quality! I definitely wouldn't put ceramics in there, it's sommat I thought about, and definitely not worth it, stick them in your hubs, jockey wheels and b/b.
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 As Mike mentioned, none of these bearings are really doing the job for which they were designed. Bits of suspension are highly loaded and move up and down through a limited range, most bearings are designed for things that continuously rotate. They're also not generally sealed in the sense of "able to keep water and grit out" - frame designs that include supplementary bearing protection help a bit.
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You just spurred me to send an e-mail to specialized over my collapsed ti-railed alias saddle that bent in the nov of 2007 and has lain lost in my house for over a year.
good ole specialized..recieved my new saddle today
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Can anyone actually see anything? Glad it got sorted though, they are a damn good company.
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Can anyone actually see anything? Glad it got sorted though, they are a damn good company.
I thought it was Andy's pictures of the snow.
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sorry bit of an odd post Got the phenom saddle with the chromoly rails in the end..he offered the ti ones but i went for the durability of the steels ... cheers mike for the advice
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