installing Shiman Hollowtech crank

I stripped a thread in a bolt hole while replacing worn chainrings on my
everyday bike, and decided it would be best to replace the cranks. I
went for the Shimano Hollowtech model FC-T661, like this one:
http://www.bike-import.ch/katalog/20...175mm__3*9fach


Everything seems to now work fine, and the crank turns freely, However,
I was surprised at how much force it took to push the axle (attached to
the right side crank) through the bearings. I had to help it along with
a hammer (padded by a piece of wood). On the one hand it seems
reasonable that this would be a tight fit because there shouldn't be any
play between axle and bearings, so maybe this is normal. But on the
other hand I worry: Could I have damaged the bearing, or put stress on
it by applying so much sidewards-directed force? In that case would I
expect the bearing to wear out unusually soon? Is there anything that
could/should be done now?

Earlier "Octa-link" bottom brackets seemed fine, and the bike was bought
at a good bike shop, so I would assume that the bottom bracket shell was
properly faced.

Thanks for any advice--I replaced the cranks on another bike maybe 5 or
6 years ago, but don't remember just how things went that time.

Ned

Ned Mantei wrote:
I stripped a thread in a bolt hole while replacing worn chainrings on
my everyday bike, and decided it would be best to replace the cranks.
I went for the Shimano Hollowtech model FC-T661, like this one:
http://www.bike-import.ch/katalog/20...175mm__3*9fach


Everything seems to now work fine, and the crank turns freely,
However, I was surprised at how much force it took to push the axle
(attached to the right side crank) through the bearings. I had to
help it along with a hammer (padded by a piece of wood). On the one
hand it seems reasonable that this would be a tight fit because there
shouldn't be any play between axle and bearings, so maybe this is
normal. But on the other hand I worry: Could I have damaged the
bearing, or put stress on it by applying so much sidewards-directed
force? In that case would I expect the bearing to wear out unusually
soon? Is there anything that could/should be done now?

Earlier "Octa-link" bottom brackets seemed fine, and the bike was
bought at a good bike shop, so I would assume that the bottom bracket
shell was properly faced.

Thanks for any advice--I replaced the cranks on another bike maybe 5
or 6 years ago, but don't remember just how things went that time.

Ned

Depends on how much help you had to give it with the padded hammer.
Full-blooded swings or gentle thumps? They are a snug fit and you should
always smear the spindle with your favorite bike grease. There should have
been a plastic bellows to protect the spindle from the bottom bracket
enviromment but grease is essential to prevent rusting and facilitate
eventual disassembly. Refrigerating the right hand crank/chainwheel/spindle
assembly in the freezer compartment for a couple of hours is surprisingly
helpful too.(Shrinks the spindle ever so slightly.) Also helpful if your
domestic partner is out for those couple of hours. In any case, some
assistance is normal. Park Tool says " Fit is snug, and in some cases gentle
use of a mallet may help." On all the ones I've ever fitted even on freshly
chased and faced BB shells at least some assistance was often necessary. It
always goes in easier after subsequent disassembly for chainring replacement
or suchlike.When the spindle seems fully in a few taps with a padded
instrument ensures that the assembly is, in fact fully seated against the
right hand bearing adaptor before you fit the left crank arm, preload using
the supplied centre cap and torque up the two clamp bolts.
Now that it's together does the crank assembly rotate smoothly and silently?
If so just get out there and ride.
PH

use an overnight dry ice pack ? effortless entry

but I worry abt instant condensation on metal surfaces in transit from ice to mounted...and forever hidden...location.

so I blow the surface off with a hair dryer, leaving core shrunk.

On Sat, 02 Nov 2013 13:19:13 +0100, Ned Mantei
wrote:

I stripped a thread in a bolt hole while replacing worn chainrings on my
everyday bike, and decided it would be best to replace the cranks. I
went for the Shimano Hollowtech model FC-T661, like this one:
http://www.bike-import.ch/katalog/20...175mm__3*9fach


Everything seems to now work fine, and the crank turns freely, However,
I was surprised at how much force it took to push the axle (attached to
the right side crank) through the bearings. I had to help it along with
a hammer (padded by a piece of wood). On the one hand it seems
reasonable that this would be a tight fit because there shouldn't be any
play between axle and bearings, so maybe this is normal. But on the
other hand I worry: Could I have damaged the bearing, or put stress on
it by applying so much sidewards-directed force? In that case would I
expect the bearing to wear out unusually soon? Is there anything that
could/should be done now?

Earlier "Octa-link" bottom brackets seemed fine, and the bike was bought
at a good bike shop, so I would assume that the bottom bracket shell was
properly faced.

Thanks for any advice--I replaced the cranks on another bike maybe 5 or
6 years ago, but don't remember just how things went that time.

Ned

You said "I was surprised at how much force it took to push the axle
(attached to the right side crank) through the bearings. I had to help
it along with a hammer (padded by a piece of wood)"., which sounds
about right.

I generally use a plastic faced hammer to install the crank half, with
the axle, but it usually doesn't require a full swing of the hammer.
If you installed the crank and it turns freely then I doubt very much
whether you damaged the bearings.
--
Cheers,

John B.

shouldn t need any force whatsoever- I ruined a nice brand new octalink crank a number of years ago when they came out because I did not realize I had not matched up the splines correctly and damaged them tightening the crank bolt-soft aluminum-

a striking force will always transfer kinetic energy to damage the most vulnerable part in the chain of components- just because you made it fit does not mean nothing got damaged. that said, you might as well run with it as it is now.