ISIS Crank Related Question

[aljsk8]

forgetting the bearing issue i think the point of isis is the splines

been through many cranks because the square taper just dosnt hold it all together as well and it comes loose and then gets rounded off

so what we are saying really is keep the older bearing systems but use a splined shaft

the way i look at it bbs are cheeper than cranks and at least if you nacker a bb in 6 months it means one never gets stuck in the frame

just my $0.02

 

[scant]

22yrs of mtb & never got a BB stuck in a frame... ANTISEIZE

I dont hav a problem with square taper.. but I appreciate many people do. splines are used so that the chainline remains consistent, IE theres a dead stop & the chainset cant get any closer to the frame.

 

[Stick Legs]

Unfortunately the problem as I see it stems from the fact that the bicycle has been limited by tradition. Bullseye and Pace (among others) have tried valiantly to break the mould but the BB shell is the limiting factor.

If the bike were anything else the BB would have heat shrunk on cartridge bearings on the shaft, sitting in self centering tapered cups on a much larger outer shell. The problem seems to be the limiting shell size, a larger shell would be of more use than wider spacing.

IMHO

 

[aljsk8]

i bought a steel frame with a stuck bb - tried everything - and i mean everything

anti seize
vice method
drilling
sawing
heating
cooling

after a month i had to bin the frame

i think the main reason for splines can be seen in cars - all pulleys and axles that require a similar fitting to bike cranks are splined - so it all stays put

heres an experiment - loosen crank bolts a little on square taper cranks
ride around for a week - result nackered rounded cranks. obviously we wouldnt undo them on purpose in real life they do come loose and sometimes you dont notice until its too late

try the same thing with splines - by the time its so loose you notice but the cranks are still ok

thats my point

sorry for the rant - no offence intended

 

[scant]

Unfortunately the problem as I see it stems from the fact that the bicycle has been limited by tradition. Bullseye and Pace (among others) have tried valiantly to break the mould but the BB shell is the limiting factor.

If the bike were anything else the BB would have heat shrunk on cartridge bearings on the shaft, sitting in self centering tapered cups on a much larger outer shell. The problem seems to be the limiting shell size, a larger shell would be of more use than wider spacing.

IMHO

yup, now convince the entire bike industry

 

[andrewl]

theres a good reason why M960 was re-worked after such a short time period into M970. namely that the seals were rubbish (numerous friends to testify to this). given the large price difference again its amusing that UN72 is a better BB, espically as the entire essence of external BBs is supposed to be lengthning BB life by placing the bearings further apart.

There's two independent points there (IMO) - the wider spacing and the sealing of the bearing itself. From an engineering prespective the wider spacing and larger bearing will alway last longer than the smaller narrower assuming all other things are equal (ie sealing, materials etc). The sealing of the 960 BB or seals themselves is sometimes reported to be suspect, however in my personal experiences having them on a couple of my bikes this hasn't been the case. While the UK may be considered a cold, dark, desolate place and harsh on equipment, I drown my M960s of a regular basis (parts of Tassie are very harsh too) and they have outlasted my UN72s. It is also easy to take the seals off and clean and regrease the bearings should the need arise.

I wish more companys could be more like chris king & phil wood. IE rather than rush inferior products to the market place just to make sales, give a lengthy testing period until the product is properly fit for use.

Is that the same Chris King which spent 10 years developing a still born BB and is still developing a 1.5 headset? I think in the current market 4 years for a product is pretty good and while M960 wasn't perfect I'd hardly say it was rushed to the market (it was tested for a long time). Raceface X-type on the other hand...

I'm told that some of new newest raceface ISIS BBs have v.good life expectancy.

Based on their offerings over the last few years I wouldn't touch them. the best ISIS BB I've found is the SKF ones. Haven't met anyone who doesn't rave about them.

I guess I'm also sticking to square taper as the new standard also seems to have adopted 4bolt instead of 5bolt microdrive that doesnt allow for my favoured 20 & 30T chainrings.... anyone whos ridden the first climb of the black mountains killer loop or at high alltitude will appreciate that

Sorry can't comment on that killer loop, but am happy to join you on it if/when I make it to that part of the work, and am happy to show you some of my killer loops too

 

[scant]

i bought a steel frame with a stuck bb - tried everything - and i mean everything

anti seize
vice method
drilling
sawing
heating
cooling

after a month i had to bin the frame

i think the main reason for splines can be seen in cars - all pulleys and axles that require a similar fitting to bike cranks are splined - so it all stays put

heres an experiment - loosen crank bolts a little on square taper cranks
ride around for a week - result nackered rounded cranks. obviously we wouldnt undo them on purpose in real life they do come loose and sometimes you dont notice until its too late

try the same thing with splines - by the time its so loose you notice but the cranks are still ok

thats my point

sorry for the rant - no offence intended

a frame builders could hav got the BB out for ya. blue thread lock on crank bolts

you're not wrong, splines do make a lot more sence... although the current related problems havent entirely been ironed out yet.

 

[andrewl]

Unfortunately the problem as I see it stems from the fact that the bicycle has been limited by tradition. Bullseye and Pace (among others) have tried valiantly to break the mould but the BB shell is the limiting factor.

If the bike were anything else the BB would have heat shrunk on cartridge bearings on the shaft, sitting in self centering tapered cups on a much larger outer shell. The problem seems to be the limiting shell size, a larger shell would be of more use than wider spacing.

IMHO

Have a closer look at a 'Spanish' BB.

 

[scant]

theres a good reason why M960 was re-worked after such a short time period into M970. namely that the seals were rubbish (numerous friends to testify to this). given the large price difference again its amusing that UN72 is a better BB, espically as the entire essence of external BBs is supposed to be lengthning BB life by placing the bearings further apart.

There's two independent points there (IMO) - the wider spacing and the sealing of the bearing itself. From an engineering prespective the wider spacing and larger bearing will alway last longer than the smaller narrower assuming all other things are equal (ie sealing, materials etc). The sealing of the 960 BB or seals themselves is sometimes reported to be suspect, however in my personal experiences having them on a couple of my bikes this hasn't been the case. While the UK may be considered a cold, dark, desolate place and harsh on equipment, I drown my M960s of a regular basis (parts of Tassie are very harsh too) and they have outlasted my UN72s. It is also easy to take the seals off and clean and regrease the bearings should the need arise.

I wish more companys could be more like chris king & phil wood. IE rather than rush inferior products to the market place just to make sales, give a lengthy testing period until the product is properly fit for use.

Is that the same Chris King which spent 10 years developing a still born BB and is still developing a 1.5 headset? I think in the current market 4 years for a product is pretty good and while M960 wasn't perfect I'd hardly say it was rushed to the market (it was tested for a long time). Raceface X-type on the other hand...

I'm told that some of new newest raceface ISIS BBs have v.good life expectancy.

Based on their offerings over the last few years I wouldn't touch them. the best ISIS BB I've found is the SKF ones. Haven't met anyone who doesn't rave about them.

I guess I'm also sticking to square taper as the new standard also seems to have adopted 4bolt instead of 5bolt microdrive that doesnt allow for my favoured 20 & 30T chainrings.... anyone whos ridden the first climb of the black mountains killer loop or at high alltitude will appreciate that

Sorry can't comment on that killer loop, but am happy to join you on it if/when I make it to that part of the work, and am happy to show you some of my killer loops too

f'kin ell this thread IS going on king have massive experience in headsets, so yeh didnt take too long to make a 1.5in.
you mention yourself you dont have any experience of the new Raceface, from what i've heard the new stuff is supposed to be pretty good.

I go to Oz once every 2yrs or so... although to be brutually honest I wish I didnt have to, vastly prefer the US or NZ. nothing personal but I'm sure tassie gets as sh,te weather as wales
i'll give ya a shout if i'm in sydney next year (kingroon as well) & we can hook up for a ride.

personal experiences are all very well. but as this thread stated at the start, ISIS hasnt got a great rep. & until a viable alternative comes along I'm sticking with my zero problem freebee square taper alternative

 

[thrustyjust]

my bb's consist of.......

2 x Hope Ti square taper
1 x Phil Wood steel square taper
1 X Royce ti square taper

The only cranks that I ever had a problem with,was Middleburns,as the machining in the cranks are not flat and look rippled and gave me never ending grief,'til they got sent back to Middleburns and got told it was 'my fault' never bought another pair of those cranks and never had an issue yet. Have Race Face LP's and Syncros cranks on my bikes,don't squeak rattle and roll.
Agree with Scant on anti-seize on threads in the BB shell,but I also tap the threads clean with the correct tool before initial installation.Does make a huge difference with taking back out at a later date.
No BB is impossible to get out.I bought a Fuquay with a stuck BB,gave it to Argos frames to refinish after getting it and the seized seatpost out.No problem,cost I think a tenner.
I hope never to look at the Phil BB,but as for the others,I work for an electric motor company and the bearing cupboard is always crammed!!!!!!