Stuff you learn(t) the hard way by being your own mechanic

[NotSoBigBen]

I have varied success with PF BB's in a few of my bikes ....

Specialized Tarmac .... Fitted, done over 11000k's and been quiet, not a problem, still going strong! Very occasionally (twice I think) serviced the bearings but that's about it

Look 675 .... That BB noise (almost from new) initially drove me to drink! Due to some Di2 issues I had to remove and replace it a few times which also didn't help. I have taken to putting 3 spots of Epoxy on each side when fitting and that has solved it for me 😎 , now at just over 5500k's - it's my 'race' bike so also clearly not ridden as much 

A small detail but these are both BB30 ... I just use those 'reducer' adapters to run standard Shimano cranks

Specialized Epic S-Works .... During the initial build Grumpy ( @GrahamW ) at the The Workshop advised to use a Wheels Mfg BB adapter so I could run my Shimano crank using the appropriate threaded external cups ... Bloody good advice, over the years I changed to a SRAM crank and it only needed a change to the drive side bearing! I had done over 6000k's on it when just recently I bought an S-Works BB30 carbon crank off a friend ... Removed the Wheels Mfg Adapter and fitted PF cups. Up to now it has been good touch 🪵, probably only done about 300k's since then. Again a 'race' bike so doesn't get used that much. I however will keep that adapter close by just in case

My 2 workhorse training Trek Superflys ( 1 aluminium and 1 carbon) both have PF BB's that have worked flawlessly and quieter than a church mouse! With 6000 and 5000k's on them respectively ... On these I just service the bearings, meaning I remove the seal and push in some extra fresh grease now and then

Just thought I'd share my PF BB experience ... In general I'd say pretty good but when it's been an issue like with the Look it can make a man 'so kwaad ek borsvoed sommer 'n krokodil'!

 

[MORNE]

4 hours ago, NotSoBigBen said:

I have varied success with PF BB's in a few of my bikes ....

Specialized Tarmac .... Fitted, done over 11000k's and been quiet, not a problem, still going strong! Very occasionally (twice I think) serviced the bearings but that's about it

Look 675 .... That BB noise (almost from new) initially drove me to drink! Due to some Di2 issues I had to remove and replace it a few times which also didn't help. I have taken to putting 3 spots of Epoxy on each side when fitting and that has solved it for me 😎 , now at just over 5500k's - it's my 'race' bike so also clearly not ridden as much 

A small detail but these are both BB30 ... I just use those 'reducer' adapters to run standard Shimano cranks

Specialized Epic S-Works .... During the initial build Grumpy ( @GrahamW ) at the The Workshop advised to use a Wheels Mfg BB adapter so I could run my Shimano crank using the appropriate threaded external cups ... Bloody good advice, over the years I changed to a SRAM crank and it only needed a change to the drive side bearing! I had done over 6000k's on it when just recently I bought an S-Works BB30 carbon crank off a friend ... Removed the Wheels Mfg Adapter and fitted PF cups. Up to now it has been good touch 🪵, probably only done about 300k's since then. Again a 'race' bike so doesn't get used that much. I however will keep that adapter close by just in case

My 2 workhorse training Trek Superflys ( 1 aluminium and 1 carbon) both have PF BB's that have worked flawlessly and quieter than a church mouse! With 6000 and 5000k's on them respectively ... On these I just service the bearings, meaning I remove the seal and push in some extra fresh grease now and then

Just thought I'd share my PF BB experience ... In general I'd say pretty good but when it's been an issue like with the Look it can make a man 'so kwaad ek borsvoed sommer 'n krokodil'!

 

Im sure someone will correct me but I was under the impression that the whole epoxy PF BB thing was a common spez (carbon frame) practise - there was even mos that thread a few years ago about the guy and the spez shop and his cracked BB due to workshop error. 
 

As already mentioned, i also never had issues with the bike i had that used a PF42 standard with shimano reducing cups.
 

Also, i only use Wheels Mfg bb’s these days. I have them on all my bikes. They are worth their weight in gold. The dub one on my enduro bike has ~7000km on it and it spins as smooth and free as the day i put it in. Their seals are just amazing. 

 

[NotSoBigBen]

4 minutes ago, MORNE said:

Im sure someone will correct me but I was under the impression that the whole epoxy PF BB thing was a common spez (carbon frame) practise - there was even mos that thread a few years ago about the guy and the spez shop and his cracked BB due to workshop error. 
 

As already mentioned, i also never had issues with the bike i had that used a PF42 standard with shimano reducing cups.
 

Also, i only use Wheels Mfg bb’s these days. I have them on all my bikes. They are worth their weight in gold. The dub one on my enduro bike has ~7000km on it and it spins as smooth and free as the day i put it in. Their seals are just amazing. 

 

I do recall that ... in my case both the Specialized's have been fine *searches desperately for wood nearby to touch*

[MrJacques]

On 1/21/2025 at 12:21 PM, droo said:

"A DIY solution" is a very broad spectrum, I haven't seen what you're capable of... no offence meant, but I've seen some questionable work in my time.

But yes, getting it in straight is the most important bit. And the easiest thing to break in the process is the sleeve between the two cups, which will go out of alignment if a mouse farts in the next room.

This is one of those jobs that I'd say either get the tool or get the LBS to do it for you. Unless you have a carpenter's bench vise, which is about the only non-standard tool I can think of with big enough parallel jaws to get the job done.

You weren't kidding about the sleeve! After pressing in both sides I saw it went in skew. Thankfully it didn't break (although I would have had the old one as a spare), and I was able to tap the right side of the BB out without any noticeable damage to the bearing. Managed to get it in straight on the 2nd try and the cranks turn smoothly

Edited January 30 by MrJacques

[Eugene]

I learned this weekend that if you install a new derailleur hanger, you should also check your high low settings. 

Changed into the largest cog whilst on the road and derailleur whacked straight into the spokes and broke at least one. 

I was so angry with myself for not checking. Replacing a spoke is beyond my expertise as a home mechanic

[MrJacques]

11 hours ago, Eugene said:

I learned this weekend that if you install a new derailleur hanger, you should also check your high low settings. 

Changed into the largest cog whilst on the road and derailleur whacked straight into the spokes and broke at least one. 

I was so angry with myself for not checking. Replacing a spoke is beyond my expertise as a home mechanic

I would not have thought about checking the limits when replacing a hanger. I assume the old one was skew / broke and may have thrown out the settings? Or maybe the new one installed differently? I think at least one of the limit screws presses against the hanger.

[Dexter-morgan]

Well, here is my bit of embarrassing experience. I had to install a new bottom bracket om my Trek Top Fuel and ended up Cross threading the Drive side, when it became a bit difficult to screw in I thought it was the blue-thread lock that was on it, it was only as mission to remove, clean the threads properly and get it in 100% straight, after some choice words I managed to get both sides in properly.

[MrJacques]

3 hours ago, Dexter-morgan said:

Well, here is my bit of embarrassing experience. I had to install a new bottom bracket om my Trek Top Fuel and ended up Cross threading the Drive side, when it became a bit difficult to screw in I thought it was the blue-thread lock that was on it, it was only as mission to remove, clean the threads properly and get it in 100% straight, after some choice words I managed to get both sides in properly.

Pressfit solves this

[NotSoBigBen]

13 minutes ago, MrJacques said:

Pressfit solves this

And then adds squeaking and creaking some say 🤪

[David Marshall]

8 hours ago, MrJacques said:

I would not have thought about checking the limits when replacing a hanger. I assume the old one was skew / broke and may have thrown out the settings? Or maybe the new one installed differently? I think at least one of the limit screws presses against the hanger.

When you fit a new hanger you should align it in the frame with a proper tool which makes it a more challenging DIY task. The limit screws should not need much adjustment unless you are changing the wheel as well.

[droo]

12 minutes ago, David Marshall said:

When you fit a new hanger you should align it in the frame with a proper tool which makes it a more challenging DIY task. The limit screws should not need much adjustment unless you are changing the wheel as well.

Or you've been tweaking them to compensate for a bent hanger...

[Eugene]

On 2/4/2025 at 4:53 PM, droo said:

Or you've been tweaking them to compensate for a bent hanger...

That us probably it

[Eugene]

On 2/4/2025 at 7:49 AM, MrJacques said:

I would not have thought about checking the limits when replacing a hanger. I assume the old one was skew / broke and may have thrown out the settings? Or maybe the new one installed differently? I think at least one of the limit screws presses against the hanger.

The B screw does, but not the limit screws