Forum menu
Well, my Shimano HTII BB came with the words "improved seals" on the packet.
Following the last round of the Thetford Winter Series, they've now got that slightly stiff feeling about them that bottom brackets shouldn't have. I've taken square taper through similar conditions (i.e. absurdly wet and gloopy) without any problem.
Once they finally disintegrate I might try an Acros, or even a Hope before I go back to square taper though.
EDIT:
Maybe the only way old UN72's are superior is in their fit and forget nature. As far as I can see, HT2 is superior in every other way.
Perhaps HT2 just can't cope with being immersed and square taper can?
I think that the bearing design of HTII cranks is fundamentally flawed. I will never be buy one. I will be sticking with conventional cartridge bottom brackets, I have Octalink on both my bikes.
PS I am a bike luddite, I still use 8 speed so as tonot have to use a paperchain.
nicko74
My square tapered RS7s rounded off after about 10 months. I made sure they were properly tightened as well. Especially after previous cheap square tapered cranks I had did the same.
They were on my one and only bike which gets used a lot though.
Still. The chainrings lasted.
Funny..., this rounding off problem is one I've never had with any square taper crank. Too soft an alloy for the cranks?
Now, I don't want to sound pedantic (but I know I will), but can someone explain to me how on earth do you round a square taper bottom bracket (ok technically you can round a square taper by being an ham fisted moron but for the sake of the argument lets say you are not)?
Mine is still perfectly square after 4 years of use on my switch and now my meta 5.5 for what most of people will call free ride (which is just standard riding). Rode in some super rocky trails, free ride shuttle days (that include the 6 foot jumps/drops), number 00 at an enduro last sunday (with very long stages). And yet it is perfectly square.
I am very confident I reach the over 40 000 m of altitude loss with it and it still doesn't have rounded or get any play. I think some people should spend more time at the LBS and less on forums...
Perhaps HT2 just can't cope with being immersed and square taper can?
that's my suspicion...
Perhaps HT2 just can't cope with being immersed and square taper can?that's my suspicion...
Quite possibly. My GXP got a fair dunking at the first Brass Monkeys mud bath at the end of last year. I did give it a good clean when I got home, but it didnt seem to let anything in.
No idea how they round off juan.
I always do my own bike servicing.
Maybe it's the constant sludge of Pennine grit stone that does it.
Perhaps that's where I'm going wrong. 🙂
When I first got HT2 cranks the bearings died really fast. Got new bearings and same thing again. Had the BB faced (basically just a bit of paint evened out) and the next bearings lasted ages... Untill I swapped frames and they died very quickly. Had the new frame faced, and the next bearings lasted ages till the bike got stolen.
Based on my experiences I'm assuming HT 2 requires a really even BB and then it can be good (not saying it will last longer then square tapier).
I've been using HT2 on lots of different frames, never faced the shell, and have had no issues, again, I'm not complaining about the year and a half lifespan, considering the mileage.
I've got HT2 on 2 bikes and square taper on the third, oh and horrible horrible Truvativ Isoflow on the other one, but it doesn't count. HT2 BBs don't seem to last as long, the last ST BB I fitted into my "retro" went in in about 1991 and came out in 2008, however many thousands of miles later. Whereas the XT BB I fitted in 2009 isn't going to see 2010 out, with oh maybe 1/10th as many miles.
The cranks are better though, and I don't consider the lifespan on a £30 BB to be too terrible if it lasts a year. Now that Octalink, that's disasterously awful.
Gonna stick my neck out...
I think Superstar have cracked the problem with ISIS BB. Mine is 18mths incl 2 winters and still smooth. It's because they have larger loose bearings instead of tiny cartriges.
And they are cheap and stiff and weight less than a Square taper eqv.
I think Superstar have cracked the problem with ISIS BB
wow! Loose ? You mean seperate balls ?
Chorlton, do you fit the crank with a torque wrench and periodically check the crank bolts?
yeah it think loose bearing means "Not in a cartridge", a bit like in a Shimano hub.
[url= http://www.bikeradar.com/gear/category/components/bottom-bracket/product/isis-bb-10-35491 ]Bike radar review[/url]
Superstar ISIS BB ontop, some other brand below
[img] 
[/img]
Chorlton, do you fit the crank with a torque wrench and periodically check the crank bolts?
No. Not with a torque wrench.
I just did it up bastard tight. (Too tight?) With a thin smearing of grease on the bb axle. Not pro I know. 🙂
I was constantly checking the crank bolts. Seeing as it was £200.
if you don't have a torque wrench the settings are:
into alloy tighten till you fart
into steel tighten till you sh1t
[b]Buzzlightyear[/b] - You want to ask for a refund there, they've got holes in them 😉
Again Ive had the (HT2) cranks off at least every week to clean, post every ride in the winter. ... Maybe the only way old UN72's are superior is in their fit and forget nature. As far as I can see, HT2 is superior in every other way.
I'm not sure you can say that HT2 is superior in every other way when you have to remove them every week to clean! Who the **** wants to have to do that!?
The only way I can see them (HT2 bearings) failing is due to poor maintenance, or poor instalation.
I think small bearings and poor seals was also a factor.
Chris king htII bearings here on 2 bikes and no
issues unlike superstars and acros which both failed
in 2 and 6 months respectivly.
Saw this:
"Always clean and lightly grease the axle tapers or splines before fitting cranks. This contradicts advice which is often given, but anyone suggesting that grease shouldn't be used either doesn't have any mechanical understanding or has a vested interest in shortening the life of your cranks."
on http://www.highpath.net/ Cycle information BB
The bearings on Truvativ GXP are shockingly bad but
http://www.hopegb.com/page_mep_force_57.html
XTR HT2 crankset now on its 4th bike in 5 years, wonderfully light piece of kit.
Middleburn rings replaced the Shimano ones at 1 year old, just replaced the middle ring with another Middleburn.
After replacing Shimano BB's yearly (and not much use), I put on a Hope ceramic on the 2nd bike its now on its 3rd bike. Did over 2500 miles last year.
I do though agree with the others, maintenance and installation are the key.
juan:
it's always on the non drive side for me, and apparently comes about because I stand on the pedals with my left foot back.
Allegedly, this causes the crank bolt to back off ever so slightly, which allows play in the crank/ BB interface, which in turn knacks the taper.
In the past 7 years I've done it with one Octalink crank and 2 square taper cranks (ran Octalink for 2 years and ST for 5).
nicko how did you get your crank installed? The key is to tighten them as much as you can with some grease on the square tapper.
Ah, see the grease thing is a big bone of contention - I've heard more people say no grease than say grease, so have always done it without grease previously. I can understand though, that if you grease the taper then you can get the bolt a fair bit tighter. But I've tried threadlock on the crank bolts previously, tightening them up when they loosen and so on, and the net result has been the same until now 🙁