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Trek BB90



 
 
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  #11  
Old August 9th 20, 10:29 PM posted to rec.bicycles.tech
Mark J.
external usenet poster
 
Posts: 840
Default Trek BB90

On 8/8/2020 6:07 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.


Yup. I changed the BB90 bearings on my Domane without fixing the
"click." Turns out it was the "IsoSpeed" bearing at the seat cluster.
(Google Domane IsoSpeed if the idea of a bearing in the seat cluster
sounds bizarre.) It had rusted (too many rain rides, I guess).
Replaced that and noise went away.

I think some Madones now have the IsoSpeed seat cluster; worth a check.

Mark J.
Ads
  #12  
Old August 9th 20, 11:20 PM posted to rec.bicycles.tech
Tom Kunich[_2_]
external usenet poster
 
Posts: 1,318
Default Trek BB90

On Sunday, August 9, 2020 at 2:29:42 PM UTC-7, Mark J. wrote:
On 8/8/2020 6:07 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.

Yup. I changed the BB90 bearings on my Domane without fixing the
"click." Turns out it was the "IsoSpeed" bearing at the seat cluster.
(Google Domane IsoSpeed if the idea of a bearing in the seat cluster
sounds bizarre.) It had rusted (too many rain rides, I guess).
Replaced that and noise went away.

I think some Madones now have the IsoSpeed seat cluster; worth a check.

Mark J.

Mine is a 2012 before Trek decided that they were more clever than Lance Armstrong.
  #13  
Old August 10th 20, 01:14 AM posted to rec.bicycles.tech
AMuzi
external usenet poster
 
Posts: 13,447
Default Trek BB90

On 8/9/2020 11:47 AM, Tom Kunich wrote:
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.



Before doing anything else, find an able willing assistant
(who is not our age with hearing impairment).

Get on your bike with your shoes and hold the front brake
firmly tight. Lean on something (doorway, chair back) with
you other hand. Press as hard as you are able on the right
crank (around 3:00 position). Backpedal and repeat for the
left crank. Hard. Continue in that cycle as assistant
listens near the BB area, at the rear wheel and so on. I
find a finger on a chainring bolt or RH cup/bearing or pedal
spindle to sometimes be edifying (you can talk with
assistant as you do this so there are no mangled fingers). A
mechanic's stethoscope is also useful.

We replace some crank bearings at rider request which
sometimes are a misdiagnosis of a
pedal/skewer/spoke/chainring bolt/saddle noise.

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


  #14  
Old August 10th 20, 02:48 AM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 4,018
Default Trek BB90

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
  #15  
Old August 10th 20, 05:36 AM posted to rec.bicycles.tech
John B.[_3_]
external usenet poster
 
Posts: 5,697
Default Trek BB90

On Sun, 09 Aug 2020 18:48:27 -0700, Jeff Liebermann
wrote:

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.

:-) The classic method to repair out of round holes is (FIRST)
obtain a bearing with an O.D. larger then the current and then bore
the hole to fit the new 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

--
Cheers,

John B.

  #16  
Old August 10th 20, 03:37 PM posted to rec.bicycles.tech
JBeattie
external usenet poster
 
Posts: 5,870
Default Trek BB90

On Sunday, August 9, 2020 at 9:36:50 PM UTC-7, John B. wrote:
On Sun, 09 Aug 2020 18:48:27 -0700, Jeff Liebermann
wrote:

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.

:-) The classic method to repair out of round holes is (FIRST)
obtain a bearing with an O.D. larger then the current and then bore
the hole to fit the new 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

--
Cheers,

John B.


Ruckus, our local carbon repair shop, has a number of methods for fixing carbon BBs. I think they would just build up the shell and ream to dimension with something like Tom's bike. On standard BB30 shells, they can also bond-in a piece of tube made by Enve and just turn the bike into PF30. https://ruckuscomp.com/news/2015/10/09/30-is-the-new-30 Tom can also buy the OS bearings made for sloppy Trek frames.

-- Jay Beattie.
  #17  
Old August 10th 20, 04:37 PM posted to rec.bicycles.tech
Tom Kunich[_2_]
external usenet poster
 
Posts: 1,318
Default Trek BB90

On Sunday, August 9, 2020 at 5:15:01 PM UTC-7, AMuzi wrote:
On 8/9/2020 11:47 AM, Tom Kunich wrote:
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.

Before doing anything else, find an able willing assistant
(who is not our age with hearing impairment).

Get on your bike with your shoes and hold the front brake
firmly tight. Lean on something (doorway, chair back) with
you other hand. Press as hard as you are able on the right
crank (around 3:00 position). Backpedal and repeat for the
left crank. Hard. Continue in that cycle as assistant
listens near the BB area, at the rear wheel and so on. I
find a finger on a chainring bolt or RH cup/bearing or pedal
spindle to sometimes be edifying (you can talk with
assistant as you do this so there are no mangled fingers). A
mechanic's stethoscope is also useful.

We replace some crank bearings at rider request which
sometimes are a misdiagnosis of a
pedal/skewer/spoke/chainring bolt/saddle noise.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

I hadn't thought of a lose crank bolt which could offer the same sort of noise in the same sort of position.
  #18  
Old August 10th 20, 04:40 PM posted to rec.bicycles.tech
Tom Kunich[_2_]
external usenet poster
 
Posts: 1,318
Default Trek BB90

On Monday, August 10, 2020 at 7:38:03 AM UTC-7, jbeattie wrote:
On Sunday, August 9, 2020 at 9:36:50 PM UTC-7, John B. wrote:
On Sun, 09 Aug 2020 18:48:27 -0700, Jeff Liebermann
wrote:

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.

:-) The classic method to repair out of round holes is (FIRST)
obtain a bearing with an O.D. larger then the current and then bore
the hole to fit the new 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

--
Cheers,

John B.

Ruckus, our local carbon repair shop, has a number of methods for fixing carbon BBs. I think they would just build up the shell and ream to dimension with something like Tom's bike. On standard BB30 shells, they can also bond-in a piece of tube made by Enve and just turn the bike into PF30. https://ruckuscomp.com/news/2015/10/09/30-is-the-new-30 Tom can also buy the OS bearings made for sloppy Trek frames.

-- Jay Beattie.

If I cannot get it to work with correct size bearings I would take it to the Trek factory store in Livermore so that any serious damage would be on their hands. I could use a new Madone if they ruin the old one.
  #19  
Old August 10th 20, 04:47 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 10,538
Default Trek BB90

On 8/9/2020 8:14 PM, AMuzi wrote:
On 8/9/2020 11:47 AM, Tom Kunich wrote:
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.



Before doing anything else, find an able willing assistant (who is not
our age with hearing impairment).

Get on your bike with your shoes and hold the front brake firmly tight.
Lean on something (doorway, chair back) with you other hand. Press as
hard as you are able on the right crank (around 3:00 position).
Backpedal and repeat for the left crank. Hard. Continue in that cycle as
assistant listens near the BB area, at the rear wheel and so on.Â* I find
a finger on a chainring bolt or RH cup/bearing or pedal spindle to
sometimes be edifying (you can talk with assistant as you do this so
there are no mangled fingers). A mechanic's stethoscope is also useful.

We replace some crank bearings at rider request which sometimes are a
misdiagnosis of a pedal/skewer/spoke/chainring bolt/saddle noise.


I strongly agree with Andrew's method. I've used it myself (although not
with an assistant).

If an assistant is helping and a mechanic's stethoscope isn't available,
a workable substitute can be a dowel, yardstick etc. Hold one end
touched to the suspected part and the other end held against one's ear.
Before buying the stethoscope, I used that trick on car engines.

--
- Frank Krygowski
  #20  
Old August 10th 20, 04:51 PM posted to rec.bicycles.tech
Frank Krygowski[_4_]
external usenet poster
 
Posts: 10,538
Default Trek BB90

On 8/10/2020 11:37 AM, Tom Kunich wrote:
On Sunday, August 9, 2020 at 5:15:01 PM UTC-7, AMuzi wrote:
On 8/9/2020 11:47 AM, Tom Kunich wrote:
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.

Before doing anything else, find an able willing assistant
(who is not our age with hearing impairment).

Get on your bike with your shoes and hold the front brake
firmly tight. Lean on something (doorway, chair back) with
you other hand. Press as hard as you are able on the right
crank (around 3:00 position). Backpedal and repeat for the
left crank. Hard. Continue in that cycle as assistant
listens near the BB area, at the rear wheel and so on. I
find a finger on a chainring bolt or RH cup/bearing or pedal
spindle to sometimes be edifying (you can talk with
assistant as you do this so there are no mangled fingers). A
mechanic's stethoscope is also useful.

We replace some crank bearings at rider request which
sometimes are a misdiagnosis of a
pedal/skewer/spoke/chainring bolt/saddle noise.
--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

I hadn't thought of a lose crank bolt which could offer the same sort of noise in the same sort of position.


Years ago, in the middle of nowhere (well, western Ohio) on a solo tour,
I had one of those loose crank bolt events. It was a great feeling to go
from impending doom to silence and joy using only an allen wrench.


--
- Frank Krygowski
 




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