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It's not a huge surprise that this bike has had the pivot bearings seize. The bearings in my 2008 Epic's rear suspension seized after about a year's use too. That bike was just about to have the bearings replaced but ended up being stolen first.:(

I'm going to look into seeing if I can get some higher quality bearings fitted than the stock Specialized ones when they're replaced.

The bike is still rideable and was working well enough today. Having some more rebound damping on the rear shock helped, even if the ride was quite hard. It's not as intrusive as riding with a faulty E100 fork or a broken bottom bracket anyway.:)

It's actually getting lighter by the week too. I took the seatpost out and even more bits of the corroded aluminium bottom bracket shell poured out when I turned it upside down.
 

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WR304 said:
It's not a huge surprise that this bike has had the pivot bearings seize. The bearings in my 2008 Epic's rear suspension seized after about a year's use too. That bike was just about to have the bearings replaced but ended up being stolen first.:(

I'm going to look into seeing if I can get some higher quality bearings fitted than the stock Specialized ones when they're replaced.

The bike is still rideable and was working well enough today. Having some more rebound damping on the rear shock helped, even if the ride was quite hard. It's not as intrusive as riding with a faulty E100 fork or a broken bottom bracket anyway.:)

It's actually getting lighter by the week too. I took the seatpost out and even more bits of the corroded aluminium bottom bracket shell poured out when I turned it upside down.
IMO quality of bearings is not the issue, it is the quality of the shielding, and the fact that water and muck can get in. The 2 dropout bearings are a 68002RS, but as far as bearing quality goes, it might actually be better to go for a lower spec bearing (e.g. C2), rather than the Spec one (probably C3 or C"N"). The theory being that looser tolerances will allow for continued function despite the presence of grit. The other approach is to go with a "snap ring seal" (i.e. SRS rather than 2RS) - this provides a better bearing shield desiged to resist water ingress. However IIRC these only come with a C5 bearing.... If you go to a good bearing shop you will find that there are a variety of different options within the 2RS line as well, some shield designs are different with seperate lips top and bottom ("2RS LLU" IIRC) which to my thinking would be a good idea for suspension rather than a shield with a single lip. When my '09 comes up for it's birthday I will be replacing the bearings and will decide which ones to go with...

The other thing I have looked at is fashioning some plastic shields for the top and front of the 2 rear bearings to prevent the "splash" of debris from lodging in the bearing cracks.

WRT the BB, I checked mine the other day and was relieved to find it dry, but it does need a drain hole to be drilled through the Aluminium BB shield for me to be happy. Another project for winter.
 

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In terms of the water and corrosion issues with the bottom bracket and pivot bearings of my bike it's worth noting that it's never cleaned with a jetwash or hosepipe. The water problems are just from riding it in the UK.

Arguably the rear pivot bearings seizing are at least partly my own fault for not taking it apart and greasing them regularly. Apparently they aren't always smooth even when brand new. Have a look at these pictures where PB Matrix found that one of the bearings on his brand new 2010 Stumpjumper FSR was already seized.

http://forums.mtbr.com/showpost.php?p=6322093&postcount=38

What I'd really like would be to have pivot bearings with an integrated grease port on them. No need to disassemble the bike just use a grease gun to flush clean grease through the bearing every now and then.

Some sort of shield for the bearings would probably work quite well. It's not going to do anything for UK rain and mud but if you ride a lot in dusty conditions then just putting some electrical tape over the pivots as pictured below could help prolong the bearing life. The picture below is of egebhardt's Specialized Epic with tape covering the bearings.

http://forums.mtbr.com/showpost.php?p=6792384&postcount=9

Pictured below: Covering the suspension pivot bearings with tape may make them last longer in dusty conditions
 

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WR304 said:
Riding my Epic with the rear brain on full soft today was a bit of a surprise - it was exactly the same as with the rear brain on full firm.
I had to wait a few weeks for the bike shop to find time but I finally had some new rear suspension pivot bearings fitted and went to collect it today. What a difference - with the rear shock deflated the travel felt very smooth.

I didn't get to actually take the bike home though. The barely functioning seized pivot bearings had clearly been masking the other major issue which was that the Specialized rear shock had failed. There was no brain platform and a really nasty notch/ squish at the beginning of the shock's travel. No wonder I couldn't tell any difference between brain settings when riding. That's three fork failures and one rear shock failure so far.

The rear shock has gone back to Specialized to be repaired under warranty so I'm without a bike again this week. Intervals on the Turbo Trainer are my favourite.:skep:
 

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Discussion Starter · #345 ·
I had a "creak" which I thought was coming from my bb after having the bearings replaced there. It ended up coming from a loose horst link pivot. Since it was loose, I took it apart and regreased the bearings. Pretty easy job. The only challenge I had was that I could not remember which way the cone washers went back in (i was doing this of course 1/2 hr b4 I needed to leave for a race! btw the smaller diameter fits towards the bearing....). One issue I did have was that the chain ring bolts were coming loose, so I check those periodically.

I've had a sequence of mechanicals lately but nothing to do w/ the bike itself : broke a chain during a race, next ride bent der hanger, next ride my freehub stopped working, and now need to replace my cassettes as they are skipping w/ the new chain.

On comparison note, i did a short ride on the high end carbon gary fisher FS "whatevertheyarecalled". Very comfortable and easy on the body. Much more upright riding position and I could see it being a great bike if you were going to ride around the woods all day. Though it was only a couple of lbs heavier than my sworks, i did notice right away (and i am not a picky rider) how much work it took to get it going and to get it uphill. Made me appreciate the snappyness of my swork. Its one of my favorite things about the swork. It's such an easy bike to throw around the trail.

On the 29er note, I can imagine that Spech is working on a fully decked out carbon epic 29er and wish they would work on a 650b instead. I think that would complement what the swork does so well now...
 

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Did you service all the pivot bearings on your Epic? Were they all still smooth? On my bike the Horst link pivot bearings had seized completely but apparently the two suspension pivots by the bottom bracket were in a very bad state too. They're quite exposed to water and mud coming off the back wheel.

Was it a Gary Fisher Superfly 100 29er that you tried?

http://fisherbikes.com/bike/model/superfly-100

Did you get a chance to experiment with different combinations of propedal and shock pressure in the Gary Fisher's rear shock? With a non-brain shock such as the Fox RP2/ RP23 you often need to set it up by over pressuring the shock (running significantly higher pressures than the recommended starting point for your weight) in order to minimise pedal bob. You end up with a firm ride but the bike pedals quite well. The rear suspension of the Giant Anthem X2 that I tried a few weeks ago was quite sensitive to small changes in rear shock pressure. You can take that to extremes of course where the rear shock has so much air in that the rear suspension barely moves.:)

Edit: The interesting thing about the carbon fibre Gary Fisher Superfly 100 29er if you search the mtbr.com Gary Fisher subforum is that there are quite a few threads about the frames breaking. I have to say the bike looks really nice in pictures but there do seem to be question marks over its reliability.

http://forums.mtbr.com/showthread.php?t=599068

http://forums.mtbr.com/showthread.php?t=620127

http://forums.mtbr.com/showthread.php?t=626697
 

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Discussion Starter · #347 ·
yeah, it was the top line Superfly. I was too lazy to look it up :rolleyes:! I had the propedal on and actually was explaining the different setting to it's new owner who is significantly heavier than I. I loved my propedal setting on my Yeti AsR. It was more of an issue of weight and getting the bike going than pedal bob. Don't get me wrong, it felt like a really nice bike, just not as "racy" as the epic. I like the "snappy" feeling of my epic. It has a certain: you pedal and bang, off you go :thumbsup:

I have not yet looked at the main pivot bearings. Actually I tried but my lbs tightened the inner crank screw too tight when they worked on my bb, so I can't get the crank off. I am sure they need some serious tlc though!

A recent thing I added to my Swork are the white Schwable Rocket Rons. The bike looks almost too blinged out!
 

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That sounds like after the bike shop replaced my bottom bracket.:eekster:

They'd put the plastic preload ring of the left hand Shimano Deore XT crank back on so tight that it wouldn't budge with the small plastic tool that you get to unscrew it. I ended up having to take the bike back to the shop where they agreed it was quite tight too. (The fix is to hit the right hand crank arm with a rubber mallet which loosens the other crank a little allowing you to unscrew the plastic preload ring).

It's a standing joke that the bike shop always have to screw the pedals on ridiculously tight as well.:)
 

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WR304 said:
That sounds like after the bike shop replaced my bottom bracket.:eekster:

They'd put the plastic preload ring of the left hand Shimano Deore XT crank back on so tight that it wouldn't budge with the small plastic tool that you get to unscrew it. I ended up having to take the bike back to the shop where they agreed it was quite tight too. (The fix is to hit the right hand crank arm with a rubber mallet which loosens the other crank a little allowing you to unscrew the plastic preload ring).

It's a standing joke that the bike shop always have to screw the pedals on ridiculously tight as well.:)
The 970 HT2 crank is pretty easy to setup wrong (like any HT2),as it relies on the correct side loading from the LHS crank to function correctly. The axial load (the preload screw in the 970) should only be 1 nm which is barely finger tight - in other words, just enough to take the slack out of the BB. Most people (including LBS's) load this up too much and wonder why the BB doesn't last (maybe thats why the LBS does it).

IMO HT2 it is a bad design because it is so easy to get wrong. It is one of the things I like about the GXP system. The GXP BB spins much better than the HT2, however in practice the GXP BB's don't last as well as HT2 due to poor sealing. Now that SRAM have proper (gutter) sealing on the GXP updates released for X.0, that is me done with HT2. As soon as a full X.0 x10 group is available, I'm in.

BTW, the 970 crank is torqued to 50nm which is very tight. Remember that the 970 uses an Octalink connection to the crank arm (unlike the 770) and this is always tight. IME, you end up replacing the LHS locknut every half dozen removals as the 8 Hex rounds off.
 

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Discussion Starter · #350 ·
WR304 said:
It's a standing joke that the bike shop always have to screw the pedals on ridiculously tight as well.:)
They put on my left pedal and I can't get the thing off!!!! I even tried banging it w/ a hammer w/ no luck :madman:

I just remembered this...:cryin: :cryin: :cryin: ... I often block it out of memory to prevent the pain!!!! but i crashed at pretty technical race and send the bike and myself, flying into a rock garden. I ended up cracking the top layer of the non drive side carbon chain stay. It's very minor and I have actually been riding the bike for a month since w/out any problems. I was thinking about applying some clear epoxy to protect the area from dirt. Any recommendation for a particular epoxy that works best on carbon?:confused: ?
 

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skiwi said:
The 970 HT2 crank is pretty easy to setup wrong (like any HT2),as it relies on the correct side loading from the LHS crank to function correctly. The axial load (the preload screw in the 970) should only be 1 nm which is barely finger tight - in other words, just enough to take the slack out of the BB. Most people (including LBS's) load this up too much and wonder why the BB doesn't last (maybe thats why the LBS does it).

IMO HT2 it is a bad design because it is so easy to get wrong. It is one of the things I like about the GXP system. The GXP BB spins much better than the HT2, however in practice the GXP BB's don't last as well as HT2 due to poor sealing. Now that SRAM have proper (gutter) sealing on the GXP updates released for X.0, that is me done with HT2. As soon as a full X.0 x10 group is available, I'm in.

BTW, the 970 crank is torqued to 50nm which is very tight. Remember that the 970 uses an Octalink connection to the crank arm (unlike the 770) and this is always tight. IME, you end up replacing the LHS locknut every half dozen removals as the 8 Hex rounds off.
Just realised you are talking about the 770, not the 970 crank. Issue is the same but the 970 uses a separate pre-laod screw attached to the LHS crank, whilst the 770 uses a plastc cap insode the LHS crank. Torque on that 770 is 1.5nm IIRC. Again, barely finger tight.
 

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Yes, the axial preload of the 970 crank should be only fingertight!
Everything works great with this crank since 2009, I love this bike :band:

Some impressions of my 2009 Epic comp with a XTR 970 crank.


.
 

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zauberer said:
Yes, the axial preload of the 970 crank should be only fingertight!
Everything works great with this crank since 2009, I love this bike :band:

Some impressions of my 2009 Epic comp with a XTR 970 crank.


.
Awsome Video,Awsome Scenery!!
I ENVY YOU for having such a great place too ride!!
 

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skiwi said:
Just realised you are talking about the 770, not the 970 crank. Issue is the same but the 970 uses a separate pre-load screw attached to the LHS crank, whilst the 770 uses a plastic cap inside the LHS crank. Torque on that 770 is 1.5nm IIRC. Again, barely finger tight.
It's a Shimano Deore XT M770 Hollowtech II chainset. The problem is that you only get that tiny plastic tool with it. If the plastic bolt ends up tight it's impossible to get any leverage at all on the circular tool to undo it.

Overtight pedals are usually because bike shops tend to have a long workshop pedal spanner like the Park Tools one. It gives lots of leverage and if you only have one of the shorter pedal spanners at home it makes it impossible to get them off again. I only live a few minutes from the bike shop so it's not a huge issue taking it back if they have overtightened something.

You'd have laughed when I had to take my (brand new at the time) 2008 Epic back to ask them to take the pedals off a few years ago. The mechanic was having to stand on the Park Tools pedal spanner to undo them they were so tight.

bellullabob said:
I crashed at pretty technical race and send the bike and myself, flying into a rock garden. I ended up cracking the top layer of the non drive side carbon chain stay. It's very minor and I have actually been riding the bike for a month since w/out any problems. I was thinking about applying some clear epoxy to protect the area from dirt. Any recommendation for a particular epoxy that works best on carbon
You can get quite a few different kits specifically for repairing carbon fibre. You should probably try at somewhere like a sailing shop.:)

Depending on how bad it it these links have a few products that look like they would be suitable.

https://www.carbonology.com/repair-moulding-kits-c-130.html

https://www.seamarknunn.com/acatalog/Epoxy_Resin___Hardner.html

Have a look at this page where they repair a damaged carbon fibre frame too:

https://activecycles.co.uk/2010/03/07/carbon-fibre-frame-repair/

zauberer said:
Some impressions of my 2009 Epic comp with a XTR 970 crank.
That's a good quality video. For anyone watching it don't forget to press the
button in order to watch it full screen.:)

.
 

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bellullabob said:
On comparison note, i did a short ride on the high end carbon gary fisher FS "whatevertheyarecalled". Very comfortable and easy on the body. Much more upright riding position and I could see it being a great bike if you were going to ride around the woods all day. Though it was only a couple of lbs heavier than my sworks, i did notice right away (and i am not a picky rider) how much work it took to get it going and to get it uphill. Made me appreciate the snappyness of my swork. Its one of my favorite things about the swork. It's such an easy bike to throw around the trail.
I just saw that the Gary Fisher brand has been discontinued. They're all called Treks now.

http://www.bikeradar.com/news/article/trek-bicycle-corporation-kills-off-gary-fisher-bicycles-26615
 
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