Bottom bracket life?

[daihard]

Thanks for the replies all.

I've been looking at Sram GXP, the look similar to the Shimano ones I've been using but can anyone confirm they're compatible before I go ahead and order?

Cheers

[bobbo89]

A lot of people over tighten the pre-loader on Shimano cranks in my experience, I used to do the same as it's very easy to do with a Shimano and it will ruin your bearings pretty quick.

[gazza285]

bobbo89 said:

A lot of people over tighten the pre-loader on Shimano cranks in my experience, I used to do the same as it's very easy to do with a Shimano and it will ruin your bearings pretty quick.

What do people use to tighten them with? I’ve got an Ice-Tools one that fits in your hand, so hand tight only.

[daihard]

That's a good point, would explain why it always seems to be the non- drive side affected too.

Guess I better order a torque wrench too!

[bobbo89]

gazza285 said:

What do people use to tighten them with? I’ve got an Ice-Tools one that fits in your hand, so hand tight only.

There's a few out there but this is one culprit as it allows people to use an allen key rather than just finger tighten it....

[gazza285]

Could be. I use one of these, you can put an Allen key in the centre, but that is for removing the bottom bracket cups, I only hand tighten the preload plug.

[bobbo89]

Yeah finger tight is all that's needed but some people almost treat it like a bolt and proper nip it up good....

[daihard]

bobbo89 said:

Yeah finger tight is all that's needed but some people almost treat it like a bolt and proper nip it up good....

I've had a crank arm fall off on me more than once so I'm definitely guilty of over tightening the pre load and crank bolts.

Will be more careful in future, hopefully this is my issue.

Cheers all

[bigdom]

It's worth buying a Torque wrench for the bike, here's a recent review on some https://www.cyclingnews.com/features/best-bike-tor...

This has just popped up on my youtube videos, which may be of help? https://www.youtube.com/watch?v=gFbvFu3NER4

Edited by bigdom on Monday 8th April 14:38

[boyse7en]

WPA said:

Shimano bearings are made of cheese, look to upgrade to something better

The one on my winter road bike just gave up the ghost after 14 years, so clearly the used to be alright! I fitted an FSA as a replacement, mainly due to it being cheap

[daihard]

bigdom said:

It's worth buying a Torque wrench for the bike, here's a recent review on some https://www.cyclingnews.com/features/best-bike-tor...

This has just popped up on my youtube videos, which may be of help? https://www.youtube.com/watch?v=gFbvFu3NER4

Edited by bigdom on Monday 8th April 14:38

Thanks for this!

[LankyFreak]

daihard said:

HT is Ragley Marley

nice. pics?

[frisbee]

daihard said:

Thanks for the replies all.

I've been looking at Sram GXP, the look similar to the Shimano ones I've been using but can anyone confirm they're compatible before I go ahead and order?

Cheers

GXP aren’t compatible, the non-driveside end of the shaft is 22mm, shimano are 24mm.

[daihard]

LankyFreak said:

daihard said:

HT is Ragley Marley

nice. pics?

[daihard]

frisbee said:

daihard said:

Thanks for the replies all.

I've been looking at Sram GXP, the look similar to the Shimano ones I've been using but can anyone confirm they're compatible before I go ahead and order?

Cheers

GXP aren’t compatible, the non-driveside end of the shaft is 22mm, shimano are 24mm.

Thanks for the info, better remove them from my basket!

[daihard]

LankyFreak said:

daihard said:

HT is Ragley Marley

nice. pics?

Managed to get the frame from CRC last year when they were half price, plus another 10% off. Wasn't fussed on red at the time but that was all they had left in my size but it's grown on me since

Picked up most of the rest second hand bar the forks which are probably overkill for what I use it for

[Mars]

daihard said:

frisbee said:

daihard said:

Thanks for the replies all.

I've been looking at Sram GXP, the look similar to the Shimano ones I've been using but can anyone confirm they're compatible before I go ahead and order?

Cheers

GXP aren’t compatible, the non-driveside end of the shaft is 22mm, shimano are 24mm.

Thanks for the info, better remove them from my basket!

... also, the GXP is not "located" at both sides. It only has a step in the shaft on one side. Technically an inferior design to the Shimano BB but I think they made it like this to avoid patent infringement with Shimano. Regardless, my GXPs seem to last about 4000 miles through all sorts of abuse including riding through deep fords and flood regularly and I'm absolutely not shy about blasting them with the jetwash.

In lockdown, SRAM GXPs were hard to get. I managed to find one but when it died, I bought a cheaper replacement which, in fairness, has lasted for 3K miles to date and still seems OK.

I also have a couple of bikes with Shimano BBs and you'd have to be really trying hard to overtighten them but as you're having problems with both bikes, I don't think it's an alignment issue. Are you fitting the spacers correctly?

[daihard]

Mars said:

daihard said:

frisbee said:

daihard said:

Thanks for the replies all.

I've been looking at Sram GXP, the look similar to the Shimano ones I've been using but can anyone confirm they're compatible before I go ahead and order?

Cheers

GXP aren’t compatible, the non-driveside end of the shaft is 22mm, shimano are 24mm.

Thanks for the info, better remove them from my basket!

... also, the GXP is not "located" at both sides. It only has a step in the shaft on one side. Technically an inferior design to the Shimano BB but I think they made it like this to avoid patent infringement with Shimano. Regardless, my GXPs seem to last about 4000 miles through all sorts of abuse including riding through deep fords and flood regularly and I'm absolutely not shy about blasting them with the jetwash.

In lockdown, SRAM GXPs were hard to get. I managed to find one but when it died, I bought a cheaper replacement which, in fairness, has lasted for 3K miles to date and still seems OK.

I also have a couple of bikes with Shimano BBs and you'd have to be really trying hard to overtighten them but as you're having problems with both bikes, I don't think it's an alignment issue. Are you fitting the spacers correctly?

I have 2 spacers on the drive side on both bikes, maybe I need to double check this too if this isn't right? Both bikes change gear fine, I thought the spacers were only to get the chain line right? Happy to be corrected if this sorts my issue

[old'uns]

Shimano Saint on 2 of mine, seem to be bulletproof.

I've swapped spacers around on one of them to get chainline right when going fro 2x to 1x, no problem as such just cranks slightly offset from centre.

[LankyFreak]

daihard said:

Managed to get the frame from CRC last year when they were half price, plus another 10% off. Wasn't fussed on red at the time but that was all they had left in my size but it's grown on me since

Picked up most of the rest second hand bar the forks which are probably overkill for what I use it for

Nice! Always liked a Ragley.