Trek BB90

When I got my Trek Madone if became rapidly clear why it was so cheap. The bearings in the BB90 were rather loose. Now there are several methods of fixing this - one is to use a strong locktite-type compound which locked the bearings in place and one is the Trek way which is to put an oversize bearing in place of the stock bearing.

With normal caution as an Engineer I chose the least damaging method first. I followed the directions on the locktite and glued the "just fits" bearing into place and allowed it to dry the requisite 48 hours.. Well, climbing one of the local hills last Tuesday the BB90 began to "click" in the same place every revolution on the drive side pedal. This means the glued drive side bearing has come loose. Inasmuch as I am presently working on the Colnago I won't look at this until later. Another choice has come up - that is to check the bearing that is presently in the Madone, to see if it is undersize. That might be the case since the bearings more easily obtained from Trek are Chinese and let's say they aren't the finest quality bearing available. Hambini of one piece BB push in bearing fame who hates BB90 also can supply NTN bearings which are exactly the right size. NTN is a Japanese bearing manufacturer that supplies the best bearings in the world.

So when I remove the bearing that is presently flopping around in there I can closely measure it if I can remember where I put my micrometers. Failing that I do have a digital caliper that is fairly accurate to two decimal places. If the bearing that is in there is undersized by any significant amount (which is common with Chinese bearings.) I will get the bearing set from Hambini and install those before going to the extreme of those oversize Trek bearings which are so oversize that they can distort the bearing cups. This screws up the bearing and generally causes premature failure though "premature" is sort of an undefined term that might mean it only lasts for 1,000 hours. Chinese bearings would probably only last for twice that anyway. NTN bearings virtually last forever under the sorts of loadings that the BB90 puts on them.

So presently I'm riding the Emonda and trying to go no lower than the 28 tooth so that I can get a little more training in my legs. I am presently at 80,000 feet of climbing when I would normally be at double that. I normally close a year off with over 200,000 feet of climbing. Judging from the way that my legs felt today after a couple of 900 foot climbs I don't think that I will make 125,000 but stranger things have happened.

On Saturday, August 8, 2020 at 3:15:40 PM UTC-7, Tom Kunich wrote:
When I got my Trek Madone if became rapidly clear why it was so cheap. The bearings in the BB90 were rather loose. Now there are several methods of fixing this - one is to use a strong locktite-type compound which locked the bearings in place and one is the Trek way which is to put an oversize bearing in place of the stock bearing.

With normal caution as an Engineer I chose the least damaging method first. I followed the directions on the locktite and glued the "just fits" bearing into place and allowed it to dry the requisite 48 hours.. Well, climbing one of the local hills last Tuesday the BB90 began to "click" in the same place every revolution on the drive side pedal. This means the glued drive side bearing has come loose. Inasmuch as I am presently working on the Colnago I won't look at this until later. Another choice has come up - that is to check the bearing that is presently in the Madone, to see if it is undersize. That might be the case since the bearings more easily obtained from Trek are Chinese and let's say they aren't the finest quality bearing available. Hambini of one piece BB push in bearing fame who hates BB90 also can supply NTN bearings which are exactly the right size. NTN is a Japanese bearing manufacturer that supplies the best bearings in the world.

So when I remove the bearing that is presently flopping around in there I can closely measure it if I can remember where I put my micrometers. Failing that I do have a digital caliper that is fairly accurate to two decimal places. If the bearing that is in there is undersized by any significant amount (which is common with Chinese bearings.) I will get the bearing set from Hambini and install those before going to the extreme of those oversize Trek bearings which are so oversize that they can distort the bearing cups. This screws up the bearing and generally causes premature failure though "premature" is sort of an undefined term that might mean it only lasts for 1,000 hours. Chinese bearings would probably only last for twice that anyway.. NTN bearings virtually last forever under the sorts of loadings that the BB90 puts on them.

So presently I'm riding the Emonda and trying to go no lower than the 28 tooth so that I can get a little more training in my legs. I am presently at 80,000 feet of climbing when I would normally be at double that. I normally close a year off with over 200,000 feet of climbing. Judging from the way that my legs felt today after a couple of 900 foot climbs I don't think that I will make 125,000 but stranger things have happened.

You should also check the crank bolt torque and maybe swap the pedals out, check the chain ring bolts and even the rear QR before pressing in new bearings. Cyclical clicks can come from places other than the BB.

-- Jay Beattie.

On Sunday, August 9, 2020 at 3:08:01 AM UTC+2, jbeattie wrote:
On Saturday, August 8, 2020 at 3:15:40 PM UTC-7, Tom Kunich wrote:
When I got my Trek Madone if became rapidly clear why it was so cheap. The bearings in the BB90 were rather loose. Now there are several methods of fixing this - one is to use a strong locktite-type compound which locked the bearings in place and one is the Trek way which is to put an oversize bearing in place of the stock bearing.

With normal caution as an Engineer I chose the least damaging method first. I followed the directions on the locktite and glued the "just fits" bearing into place and allowed it to dry the requisite 48 hours.. Well, climbing one of the local hills last Tuesday the BB90 began to "click" in the same place every revolution on the drive side pedal. This means the glued drive side bearing has come loose. Inasmuch as I am presently working on the Colnago I won't look at this until later. Another choice has come up - that is to check the bearing that is presently in the Madone, to see if it is undersize. That might be the case since the bearings more easily obtained from Trek are Chinese and let's say they aren't the finest quality bearing available. Hambini of one piece BB push in bearing fame who hates BB90 also can supply NTN bearings which are exactly the right size. NTN is a Japanese bearing manufacturer that supplies the best bearings in the world.

So when I remove the bearing that is presently flopping around in there I can closely measure it if I can remember where I put my micrometers. Failing that I do have a digital caliper that is fairly accurate to two decimal places. If the bearing that is in there is undersized by any significant amount (which is common with Chinese bearings.) I will get the bearing set from Hambini and install those before going to the extreme of those oversize Trek bearings which are so oversize that they can distort the bearing cups. This screws up the bearing and generally causes premature failure though "premature" is sort of an undefined term that might mean it only lasts for 1,000 hours. Chinese bearings would probably only last for twice that anyway. NTN bearings virtually last forever under the sorts of loadings that the BB90 puts on them.

So presently I'm riding the Emonda and trying to go no lower than the 28 tooth so that I can get a little more training in my legs. I am presently at 80,000 feet of climbing when I would normally be at double that. I normally close a year off with over 200,000 feet of climbing. Judging from the way that my legs felt today after a couple of 900 foot climbs I don't think that I will make 125,000 but stranger things have happened.

You should also check the crank bolt torque and maybe swap the pedals out, check the chain ring bolts and even the rear QR before pressing in new bearings. Cyclical clicks can come from places other than the BB.

-- Jay Beattie.

Agree. I sure want to be sure that the bearing is the problem before I knocked that loctited bearing out.

Lou

On Sunday, August 9, 2020 at 4:14:56 AM UTC-7, wrote:
On Sunday, August 9, 2020 at 3:08:01 AM UTC+2, jbeattie wrote:
On Saturday, August 8, 2020 at 3:15:40 PM UTC-7, Tom Kunich wrote:
When I got my Trek Madone if became rapidly clear why it was so cheap.. The bearings in the BB90 were rather loose. Now there are several methods of fixing this - one is to use a strong locktite-type compound which locked the bearings in place and one is the Trek way which is to put an oversize bearing in place of the stock bearing.

With normal caution as an Engineer I chose the least damaging method first. I followed the directions on the locktite and glued the "just fits" bearing into place and allowed it to dry the requisite 48 hours.. Well, climbing one of the local hills last Tuesday the BB90 began to "click" in the same place every revolution on the drive side pedal. This means the glued drive side bearing has come loose. Inasmuch as I am presently working on the Colnago I won't look at this until later. Another choice has come up - that is to check the bearing that is presently in the Madone, to see if it is undersize. That might be the case since the bearings more easily obtained from Trek are Chinese and let's say they aren't the finest quality bearing available. Hambini of one piece BB push in bearing fame who hates BB90 also can supply NTN bearings which are exactly the right size. NTN is a Japanese bearing manufacturer that supplies the best bearings in the world.

So when I remove the bearing that is presently flopping around in there I can closely measure it if I can remember where I put my micrometers. Failing that I do have a digital caliper that is fairly accurate to two decimal places. If the bearing that is in there is undersized by any significant amount (which is common with Chinese bearings.) I will get the bearing set from Hambini and install those before going to the extreme of those oversize Trek bearings which are so oversize that they can distort the bearing cups. This screws up the bearing and generally causes premature failure though "premature" is sort of an undefined term that might mean it only lasts for 1,000 hours. Chinese bearings would probably only last for twice that anyway. NTN bearings virtually last forever under the sorts of loadings that the BB90 puts on them.

So presently I'm riding the Emonda and trying to go no lower than the 28 tooth so that I can get a little more training in my legs. I am presently at 80,000 feet of climbing when I would normally be at double that. I normally close a year off with over 200,000 feet of climbing. Judging from the way that my legs felt today after a couple of 900 foot climbs I don't think that I will make 125,000 but stranger things have happened.

You should also check the crank bolt torque and maybe swap the pedals out, check the chain ring bolts and even the rear QR before pressing in new bearings. Cyclical clicks can come from places other than the BB.

-- Jay Beattie.
Agree. I sure want to be sure that the bearing is the problem before I knocked that loctited bearing out.

Lou
To look at anything you have to pull out the crank. Generally in a BB90 if you have a loose BB bearing it comes out on the drive side crank. So it isn't as if it is a difficult analysis.

On Sun, 9 Aug 2020 04:14:54 -0700 (PDT), Lou Holtman
wrote:

Agree. I sure want to be sure that the bearing is the problem before I knocked that loctited bearing out.
Lou

Agreed.

"How to Remove Loctite 2620 Red Threadlocker"
https://www.henkel-adhesives.com/us/en/insights/all-insights/blog/how-to-remove-loctite-2620.html

"How to Remove Red Threadlocker"
https://www.henkel-adhesives.com/us/en/insights/all-insights/blog/how-to-remove-red-threadlocker.html

I've also used acetone (nail polish remover) to soften Loctite.
However, both heat and acetone might be impractical on a bottom
bracket because of the damage they might do to the frame paint job.

I would try putting the bearing under tension using a bottom bracket
bearing removal tool:
https://www.google.com/search?q=bottom+bracket+bearing+removal+tool&tbm=i sch
and using a syringe to inject a small amount of acetone along the glue
line. Acetone evaporates quickly, so just keep applying small amounts
and increasing tension until the bearing starts to move.

After the bearing is out, clean out any residual Loctite with acetone
from the bottom bracket. Find an inside micrometer to measure the
inside diameter of the bottom bracket. Look for an out of round
bottom bracket. Calculate the required thickness of a brass or steel
shim and use it instead of Loctite.
https://www.amazon.com/Goodson-Shim-Stock-Assortment-Brass-5/dp/B0009RGYZO
https://www.amazon.com/s?k=0.001&rh=n%3A16413291
Aluminum foil might also work, but you'll probably need to polish the
bottom bracket to prevent tearing the foil during insertion.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Jeff Liebermann wrote:
On Sun, 9 Aug 2020 04:14:54 -0700 (PDT), Lou Holtman
wrote:

Agree. I sure want to be sure that the bearing is the problem before I
knocked that loctited bearing out.
Lou

Agreed.

"How to Remove Loctite 2620 Red Threadlocker"
https://www.henkel-adhesives.com/us/en/insights/all-insights/blog/how-to-remove-loctite-2620.html

"How to Remove Red Threadlocker"
https://www.henkel-adhesives.com/us/en/insights/all-insights/blog/how-to-remove-red-threadlocker.html

I've also used acetone (nail polish remover) to soften Loctite.
However, both heat and acetone might be impractical on a bottom
bracket because of the damage they might do to the frame paint job.

I would try putting the bearing under tension using a bottom bracket
bearing removal tool:
https://www.google.com/search?q=bottom+bracket+bearing+removal+tool&tbm=i sch
and using a syringe to inject a small amount of acetone along the glue
line. Acetone evaporates quickly, so just keep applying small amounts
and increasing tension until the bearing starts to move.

After the bearing is out, clean out any residual Loctite with acetone
from the bottom bracket. Find an inside micrometer to measure the
inside diameter of the bottom bracket. Look for an out of round
bottom bracket. Calculate the required thickness of a brass or steel
shim and use it instead of Loctite.
https://www.amazon.com/Goodson-Shim-Stock-Assortment-Brass-5/dp/B0009RGYZO
https://www.amazon.com/s?k=0.001&rh=n%3A16413291
Aluminum foil might also work, but you'll probably need to polish the
bottom bracket to prevent tearing the foil during insertion.


I think that the issue with shimming is that the required shim thickness
(half the difference in diameters) is likely to be in the “tinfoil or less�
range, which then results in excessive grief trying not to shred it on
insertion. That is where Loctite excels.

On Sunday, August 9, 2020 at 8:21:00 PM UTC+2, Ralph Barone wrote:
Jeff Liebermann wrote:
On Sun, 9 Aug 2020 04:14:54 -0700 (PDT), Lou Holtman
wrote:

Agree. I sure want to be sure that the bearing is the problem before I
knocked that loctited bearing out.
Lou

Agreed.

"How to Remove Loctite 2620 Red Threadlocker"
https://www.henkel-adhesives.com/us/en/insights/all-insights/blog/how-to-remove-loctite-2620.html

"How to Remove Red Threadlocker"
https://www.henkel-adhesives.com/us/en/insights/all-insights/blog/how-to-remove-red-threadlocker.html

I've also used acetone (nail polish remover) to soften Loctite.
However, both heat and acetone might be impractical on a bottom
bracket because of the damage they might do to the frame paint job.

I would try putting the bearing under tension using a bottom bracket
bearing removal tool:
https://www.google.com/search?q=bottom+bracket+bearing+removal+tool&tbm=i sch
and using a syringe to inject a small amount of acetone along the glue
line. Acetone evaporates quickly, so just keep applying small amounts
and increasing tension until the bearing starts to move.

After the bearing is out, clean out any residual Loctite with acetone
from the bottom bracket. Find an inside micrometer to measure the
inside diameter of the bottom bracket. Look for an out of round
bottom bracket. Calculate the required thickness of a brass or steel
shim and use it instead of Loctite.
https://www.amazon.com/Goodson-Shim-Stock-Assortment-Brass-5/dp/B0009RGYZO
https://www.amazon.com/s?k=0.001&rh=n%3A16413291
Aluminum foil might also work, but you'll probably need to polish the
bottom bracket to prevent tearing the foil during insertion.


I think that the issue with shimming is that the required shim thickness
(half the difference in diameters) is likely to be in the “tinfoil or less�
range, which then results in excessive grief trying not to shred it on
insertion. That is where Loctite excels.

+1 shimming? No chance. The difference between a press fit and loose fit is 20-30 um.
Shims with that thickness will shred.

Lou

On Sun, 9 Aug 2020 18:20:55 +0000 (UTC), Ralph Barone
wrote:

I think that the issue with shimming is that the required shim thickness
(half the difference in diameters) is likely to be in the “tinfoil or less”
range, which then results in excessive grief trying not to shred it on
insertion. That is where Loctite excels.

Most of the shim sources I listed show 0.001 inch shims. For
reference, household aluminum foil is between 0.0004 and 0.0007 inches
thick. I think you'll find that brass and steel shims are quite a bit
stronger than aluminum foil.

Shredding the shim on insertion is certainly a risk. I had use shims
to fix an industrial machine where the hole had been beaten into an
oval shape by shaft vibration. I bored and honed out the hole, but
couldn't find a bearing with an exact fit. So, I shimmed it. It took
me about 6 tries to insert the bearing without ruining the shim. What
finally worked was to pre-roll the (brass) shim into a circle, leaving
a small gap at the ends. I intentionally made the shim wider than the
bearing. I tacked the shim into the machine with a few tiny dots of
cyanoacrylate adhesive. Keep the glue dots small as they are expected
to crack as the bearing is inserted. I put some grease on the outside
of the bearing, but I suspect that wasn't necessary. Using an arbor
press, I started pushing the bearing into the machine and stopped
after about 3 mm. With the bearing firmly holding the shim in place,
I bent the excess shim material outward so that further pressing of
the bearing would not push the shim into the machine. I then
completed installing the bearing with the arbor press. When done, I
scored the exposed part of the shim with an Exacto knife, and peeled
away the excess. Methinks the same procedure will work with a bottom
bracket bearing.

However, we're all making the assumption that the replacement bearing
is correctly sized. Interference fit bearing come in various OD
sizes. It should be possible to find a replacement bearing with the
correct (interference) fit.
https://www.google.com/search?tbm=isch&q=bearing+fit+table
However, before ordering, I would pull the current bearing, remove the
Loctite, and measure the inside diameter of the bottom bracket with a
bore hole micrometer. If it's an oval, make it round before
proceding.

Hmmm... maybe it is the wrong bearing? Tripeak replacement comes in
standard and "snug-fit".
http://cycletaiwan.com/tripeak-bb90-bb95-standard-snug-fit-bearing-kit-trek-only.html
Maybe a snug-fit bearing will solve the problem without a shim?

Trek BB90 Problems Solved:
https://www.bbinfinite.com/blogs/news/trek-bb90-problems-solved-1

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On 8/8/2020 8:07 PM, jbeattie wrote:
On Saturday, August 8, 2020 at 3:15:40 PM UTC-7, Tom Kunich wrote:
When I got my Trek Madone if became rapidly clear why it was so cheap. The bearings in the BB90 were rather loose. Now there are several methods of fixing this - one is to use a strong locktite-type compound which locked the bearings in place and one is the Trek way which is to put an oversize bearing in place of the stock bearing.

With normal caution as an Engineer I chose the least damaging method first. I followed the directions on the locktite and glued the "just fits" bearing into place and allowed it to dry the requisite 48 hours.. Well, climbing one of the local hills last Tuesday the BB90 began to "click" in the same place every revolution on the drive side pedal. This means the glued drive side bearing has come loose. Inasmuch as I am presently working on the Colnago I won't look at this until later. Another choice has come up - that is to check the bearing that is presently in the Madone, to see if it is undersize. That might be the case since the bearings more easily obtained from Trek are Chinese and let's say they aren't the finest quality bearing available. Hambini of one piece BB push in bearing fame who hates BB90 also can supply NTN bearings which are exactly the right size. NTN is a Japanese bearing manufacturer that supplies the best bearings in the world.

So when I remove the bearing that is presently flopping around in there I can closely measure it if I can remember where I put my micrometers. Failing that I do have a digital caliper that is fairly accurate to two decimal places. If the bearing that is in there is undersized by any significant amount (which is common with Chinese bearings.) I will get the bearing set from Hambini and install those before going to the extreme of those oversize Trek bearings which are so oversize that they can distort the bearing cups. This screws up the bearing and generally causes premature failure though "premature" is sort of an undefined term that might mean it only lasts for 1,000 hours. Chinese bearings would probably only last for twice that anyway. NTN bearings virtually last forever under the sorts of loadings that the BB90 puts on them.

So presently I'm riding the Emonda and trying to go no lower than the 28 tooth so that I can get a little more training in my legs. I am presently at 80,000 feet of climbing when I would normally be at double that. I normally close a year off with over 200,000 feet of climbing. Judging from the way that my legs felt today after a couple of 900 foot climbs I don't think that I will make 125,000 but stranger things have happened.

You should also check the crank bolt torque and maybe swap the pedals out, check the chain ring bolts and even the rear QR before pressing in new bearings. Cyclical clicks can come from places other than the BB.

-- Jay Beattie.




+1

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Saturday, August 8, 2020 at 6:08:01 PM UTC-7, jbeattie wrote:
On Saturday, August 8, 2020 at 3:15:40 PM UTC-7, Tom Kunich wrote:
When I got my Trek Madone if became rapidly clear why it was so cheap. The bearings in the BB90 were rather loose. Now there are several methods of fixing this - one is to use a strong locktite-type compound which locked the bearings in place and one is the Trek way which is to put an oversize bearing in place of the stock bearing.

With normal caution as an Engineer I chose the least damaging method first. I followed the directions on the locktite and glued the "just fits" bearing into place and allowed it to dry the requisite 48 hours.. Well, climbing one of the local hills last Tuesday the BB90 began to "click" in the same place every revolution on the drive side pedal. This means the glued drive side bearing has come loose. Inasmuch as I am presently working on the Colnago I won't look at this until later. Another choice has come up - that is to check the bearing that is presently in the Madone, to see if it is undersize. That might be the case since the bearings more easily obtained from Trek are Chinese and let's say they aren't the finest quality bearing available. Hambini of one piece BB push in bearing fame who hates BB90 also can supply NTN bearings which are exactly the right size. NTN is a Japanese bearing manufacturer that supplies the best bearings in the world.

So when I remove the bearing that is presently flopping around in there I can closely measure it if I can remember where I put my micrometers. Failing that I do have a digital caliper that is fairly accurate to two decimal places. If the bearing that is in there is undersized by any significant amount (which is common with Chinese bearings.) I will get the bearing set from Hambini and install those before going to the extreme of those oversize Trek bearings which are so oversize that they can distort the bearing cups. This screws up the bearing and generally causes premature failure though "premature" is sort of an undefined term that might mean it only lasts for 1,000 hours. Chinese bearings would probably only last for twice that anyway. NTN bearings virtually last forever under the sorts of loadings that the BB90 puts on them.

So presently I'm riding the Emonda and trying to go no lower than the 28 tooth so that I can get a little more training in my legs. I am presently at 80,000 feet of climbing when I would normally be at double that. I normally close a year off with over 200,000 feet of climbing. Judging from the way that my legs felt today after a couple of 900 foot climbs I don't think that I will make 125,000 but stranger things have happened.
You should also check the crank bolt torque and maybe swap the pedals out, check the chain ring bolts and even the rear QR before pressing in new bearings. Cyclical clicks can come from places other than the BB.

-- Jay Beattie.
Being on the drive side it cannot be crank torque, the pedals are new so the bearings are extremely unlikely to be loose and usually make noise at the ends of the crank revolutions both top and bottom. Cyclical clicks in exactly the same location almost always means that you have a loose bottom bracket bearing. But of course before I disassemble anything I check everything out. That is what a bike repair stand is for.