UltraTorque bearing replacement issue

[stormur]

I wonder did anyone noticed same "phenomenon"...

DS crank : no problem, smooth & easy ; pull old, clean, grease , tap new, circlip, done.

NDS : Seems that bearings goes "to deep" on shaft by "standard procedure" , bearing stretch it on ID ( wider OD of shaft close to spider ?) , so bearing do not spin at all ... Only solution which worked was by try& error pressing bearing onto shaft by small increments, to position "just before" it's to much.

I tried this on 2 cranks ( Super Record and Chorus, both 2014 ) - same issue

[joeyb1000]

I have done about a dozen bearing replacements with no issues.

I use the Park tool.
I hold the crank in my hand.
Hit the tool with a hammer until the sound goes "solid".
Finished.

[stormur]

So explain why on SR crank DS went ok, on NDS didn't.Same Chorus. Then I took my new Fulcrum RS crank, repeat : DS : OK, NDS- not. ???
In both situations it looked like bearing goes to far on NDS spindle. When I pulled it into, then could easy adjust how far bearings seat, so I made it in last position when bearing work, bit far and it stuck.

[Calnago]

Something sounds wrong there. They should go on the same (at least with all Campy cranks and campy bearings). I have not worked with Fulcrum cranks but I would imagine them to be the same. Are they campy bearings you are using? How are you pressing them on the shaft? Do you have a proper press or just tapping them with a screwdriver or something. Are you pressing on the inner race as opposed to just the outer race? Perhaps if you're not using a press they are going on ever so slightly misaligned which could easily be the cause of the bearings binding. Hard to tell without actually being able to see what's going on.

[bm0p700f]

again something is amiss here. Done many U-T bearing and the bearing always press on fine both sides. I use a crown race press+ a drift with good results.

[CerveloP56Gman]

It sounds like you are using some aftermarket bearings perhaps:

Campy size is 6805N, which is 37x25x6, rather than just the 6805, which is 37x25x7. And either way it's impossible to drive the bearing on too far because there is a positive stop machined onto the crankset. It should just tap on.

Hope this helps.

[stormur]

I know that something is wrong here- reason for the posting...

Bearings are Campagnolo, straight form original package. Cranks are original as well ( to reply for next "silly" doubt ). Bearing sit before tapping/ pressing evenly on shaft , and after being "pressed" sit evenly too ( measured from shaft end distance to bearing OD race ). Zero differences in tools/ procedure between DS & NDS . On Fulcrum crank ORIGINAL bearing pulled off of the crank and tap/ pressed again. On others brand new bearings from box ( campa spare parts ).

I did replace "few" bearings sets as well in life- never had such issue ( Athena UT, Chorus , Record cranks ). Until now.

I can't see any reason why it is happening too ! But it does.

[Calnago]

All I can say is "tapping" is not the same as "pressing" and you seem to be using the two terms interchangeably. You might get away with tapping as long as you are using a method described by @bm0p700f above where he taps a crown race tool and proper drift which engages the entire inner race of the bearing evenly. It can quite easily be a little cockeyed and not going all the way on if just tapped with some tool at the sides going all round. . What about the outer seals, are they seated in the little grooves pie properly. Just hard to say without seeing it. Good luck.

[stormur]

Because I was using both methods. I tapped, and when it came out unsuccesfully, I pressed bearings. I get to the point where bearing was as close to crank arm ( end of shaft ) as possible and still run free-smooth. I tried with and without rubber seal- so there's no any influence of it... If that would be 1 crank issue only - I can understand, but 3 ??? And NDS only . Weird.

[CerveloP56Gman]

At this point you need to use a micrometer and not a vernier caliper. I'm curious what the reading will be. If it's a metric micrometer the shaft at the journal where the bearing resides should read 25.01-25.02 (1.008"). Anything more than this is badly out of spec. It would be extremely hard to get a bearing on anything bigger. The bearing ID will be perfect, exactly 25mm, but just to be safe I'd use another bearing if the shaft measures out in the range I specified.

[Calnago]

Because I was using both methods. I tapped, and when it came out unsuccesfully, I pressed bearings.

Maybe you wrecked the bearing while tapping, but the real question is, if you had a proper press to begin with why would you even consider pounding (tapping) them on in the first place. It would take some considerable "tapping" force to seat them properly I would think. Oh well, live and learn. Try it with a new bearing at this point, only press it on properly from the get go.

[stormur]

Bearings are fine. Out of crank spin like crazy. Pressed (again) spin like crazy. Campagnolo recommend tapping bearings into shaft, not pressing.

About shaft faulty OD : on 3 cranks and NDS only ???????? Please....