To all you 29er's out there!

outside the bearings put the same pressure over a larger surface area so wear slower

I'm not just on about off road durability but durability in general.

I know what you mean to me they should be sealed to the same level but it seems you only get a few thousand miles out of the bearing, with an expensive replacement vs 10s of thousands on a sq taper.

Also agree that the it all seems like a better way to connect everything. I'm just looking for some evidence of good longevity on anything other than people who have upgraded to phil bearings.

I have'nt been running external BBs for long enoug to answer that one. But I repaced the square taper set-up I had on the utility bike with the equivlient external set-up (both shimano Deore) before winter. if you wait a year I'll let you know ;)

@ GS

So why do they appear to have a shorted life?

@ GS

So why do they appear to have a shorted life?

Pixies?

...or fine grit etc. getting into the horribly exposed BB, and causing accelerated wear.

Both sound equally likely to me.

Originally Posted by TheBrick(Tommy)
What the consensus out there on middleburn cranks? I'm really temped by a (second hand) pair of these. Are they worth the money? I'm not so keen on hollowtech as researching into them the baring don't seem to have very good longevity, I'd rather have longevity.

..................

So why do they appear to have a shorted life?

IME it's primarily because people install them incorrectly. Overtightened and/or on un-faced bb shells which side loads the bearing and dramatically reduces their life. In the five years or so I've been using external bb's I haven't noticed any significant difference in longevity.

Sam

Oh, sorry, also should have mentioned there is a big difference between hollowtech and hollowtech 2. The first generation used an oversized hollow bb axle and stuffed it all in a standard sized shell. this necessitated use of much smaller bearings and these definitely do suffer from shorter bearing life. However when it all went external the bearings increased in size again and it's all good. As in the previous post though externally mounted bearings rely on a correctly faced bb shell and a closer range of torque tolerance than square tapers.

IME it's primarily because people install them incorrectly. Overtightened and/or on un-faced bb shells which side loads the bearing and dramatically reduces their life. In the five years or so I've been using external bb's I haven't noticed any significant difference in longevity.

Sam

i second that! i am guilty of installing an external BB on a bb without facing and it didn't do much for the wear, but in my experience they are last as long (maybe longer?) and feel stiffer than any square taper i have used.

p.s ISIS bb's blow. fact.

I'm a little confused about 29er frame sizing, i'm 6'5 and used to ride a 23" mountain bike (26" wheels), would a 22" 29er be necessary or could i get away with something like a 20/21?

Was wondering if the frames come up often either, i really liked the idea of a geared one but after a quick look around i can see an OTP Gary Fisher working out a lot cheaper.

Any thoughts?

Thanks

hmmm... ask sam, it's much more about the TT length you ride - i wish i was tall enough to ride an XL swift though, they look frickin ace

I'm 6'4" with a 37.5" inseam and ride an XL swift. I reckon it would fit someone a couple of inches taller pretty well. Look at TT measurements as well as head tube length (to see if the bars will be high enough if you have long legs like me) of the bikes you are interested in and compare them to your 26" bike.

hmmm... ask sam, it's much more about the TT length you ride - i wish i was tall enough to ride an XL swift though, they look frickin ace

You're right, that does look ace. I was curious how the aesthetics would change as the frame size went up actually. Will drop him a pm, thanks.

I'm 6'4" with a 37.5" inseam and ride an XL swift. I reckon it would fit someone a couple of inches taller pretty well. Look at TT measurements as well as head tube length (to see if the bars will be high enough if you have long legs like me) of the bikes you are interested in and compare them to your 26" bike.

Ah perfect, thanks for the help.

I'm after some forks to turn my Chage Scissor in to something a bit more offroad friendly. I'm on a bit of a budget so can't afford a disk brake, so far these look like the best option*:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=200456449700&ssPageName=STRK:MEWAX:IT

Does anyone else have any other suggestions for a cheap(ish) pair of forks with v brake mounts which will be good for beginner type trails. I'm happy to go second hand, rigid, suspension, anything to get me going really.

*I need to compare the a2c of these and the Charge forks on the bike at the moment, hopefully they aren't too dissimilar.

Please excuse my ignorance but is it not a bit bumpy with steel forks? I have never really ridden offroad other than a weekend across the South Downs when I was 13 or 14, one thing I remember from the trip was itchy arms from all the vibrations and bouncing around.

Agree with the difference between carbon and steel forks, bugger all difference with regards to the price.

No, i'm saying that carbon forks are not worth the extra money that you pay for them.

Looks like steel forks it is then, with them being a bit cheaper it should mean I can get things up and running a bit sooner and hopefully on the muddy stuff by May.

ah, excuse my confusion. :]

Haha no worries, i'm not exactly in the cleasest on mindsets.

Despite what people would have you believe about carbon rigid forks, they really don't make much difference to vibration damping on proper off road...people like to justify the expense they've laid out by claiming they're so much more comfortable, but if you ride hard there really isn't much in it to be honest.
If you want more comfort with rigid forks you'll get a better result with a fatter front tyre than you will from running carbon forks.
Off road will almost always be bumpy unless you go with suspension, which takes away too much fun for me.

I agree with this^

Carbon forks are good at absorbing vibrations, but not so much bumps. Nice when riding your nobbly tyres on the road, on the way to the trail. But not a big difference when actually you get there.

What they are is light. Which is what you pay a bit extra for.

Finally had a chance to take the Spot out for a spin, now that the silly amounts of late snow are disapearing here. Very very happy with it. Great balance of responsive handling and stability, climbs well, and it decends pretty well too (need to get used to the brakes). Love the feel of the frame, plus, no toe overlap! The drivechain is something else. The belt performs well, but its the combination of it with the Hope trials hub, and the relatively long (and stiff) cranks, just feels so nice.

Its just a lot of fun really :)

+1 to Scraggie Borsha(suspension forks take away the bucking bronco fun!).I started off-road 12 years ago fully-rigid and had slight shoulder problems from the bumping about.Fitted sus fork; this cured shoulder but made bike heavier and climbing worse.Eventually went back to fully rigid and realised I had developed a riding style which negated the need for suspension.I dont do extreme free-riding/North Shore stuff and it's win win all the way.

What the consensus out there on middleburn cranks? I'm really temped by a (second hand) pair of these. Are they worth the money? I'm not so keen on hollowtech as researching into them the baring don't seem to have very good longevity, I'd rather have longevity.

I've got Middleburn cranks on UN72 BB.Absolutely love 'em.BB lasting years-still no play.Get 'em !

+1 to Scraggie Borsha(suspension forks take away the bucking bronco fun!).I started off-road 12 years ago fully-rigid and had slight shoulder problems from the bumping about.Fitted sus fork; this cured shoulder but made bike heavier and climbing worse.Eventually went back to fully rigid and realised I had developed a riding style which negated the need for suspension.I dont do extreme free-riding/North Shore stuff and it's win win all the way.

I love riding a fully rigid bike of-road. Cheating with fatter tyes helps though ;)

I ride my cycloX bike on trails (35mm tyres), and it skips all over the fecking place if I try and take into a stoney corner too fast. Its a lot of fun, but I do find myself having to regain loss pace all the time.

Running 2.55" 29er tyres at less than 2 bar really makes a difference. Allows me to enter corners with a lot more speed. Making the ride as a whole more flowing (bit of a shite description maybe).

For the sort of off-roading I do. The fat tyres and fully rigid set-up just feels the most fun.

http://www.on-one.co.uk/i/q/FOOOCR26DV/on-one-cromo-26er-mtb-fork-v-brake--disc

Anyone fancy doubling up?

http://julieracingdesig.canalblog.com/albums/tandem_singlespeed_29_/photos/40915398-323_1242159820.html

@Smallfurry what tyres do you have @ 2.55" I've just ordered some WTB tyres (forgotten the name) 2.35" that where cheap, looked for 2.5" (for the front) but could not see any available in the uk.

WTB Weirwolf LT 2.55.

They is huge, and grip pretty well so far (running sub 30 PSI). Havent had a chance to really push them yet. If they pass that I'll convert them to tubeless (have everything ready). The LT stands for Low Tread, so they're not super aggressive. Apparantly a standard tread version is coming (or already out).

http://www.jejamescycles.co.uk/wtb/mtb-tyres-bcp1.html

Showing Zero stock though :(

Weirdly the Schwalbe Racing Ralph 2.4" 29er has more volume. Pricey though.
http://www.chainreactioncycles.com/Models.aspx?PartnerID=79&ModelID=45455