Shimano SM-BB52

[Deleted member 26715]

Noticed over the past few rides I'm getting some noise/feeling from the bottom bracket, holding the crank I can see movement in it, so figured I'd order a new one, only to find there are 2 different lengths, 68-73mm or 83mm. Where do I measure & can this be dome without removal so I can continue to ride, it's done about 5K miles, does that seem reasonable?

 

[Paulus]

I do believe the measurement is the width of the Bottom bracket shell.
You should be able to measure it reasonably accurately with it in situ.

 

[Chislenko]

Noticed over the past few rides I'm getting some noise/feeling from the bottom bracket, holding the crank I can see movement in it, so figured I'd order a new one, only to find there are 2 different lengths, 68-73mm or 83mm. Where do I measure & can this be dome without removal so I can continue to ride, it's done about 5K miles, does that seem reasonable?

Pair of calipers on the shell will give you the measurement. (Measuring calipers obviously not brake calipers)

 

[Ajax Bay]

Noticed over the past few rides I'm getting some noise/feeling from the bottom bracket, holding the crank I can see movement in it, so figured I'd order a new one, only to find there are 2 different lengths, 68-73mm or 83mm. Where do I measure & can this be dome without removal so I can continue to ride, it's done about 5K miles, does that seem reasonable?

(Edit delete) Longevity of BB depends on type and quality: for some, you'd be pleased with 5000 miles; others, less so.

 

[T4tomo]

1) it could be that the crank is just loose.

2) 5000 miles isnt a vast amount for a BB

3)
83mm is very unusual.
73mm usual MTB
68mm usual road.
the standard SmBB52 has a 5mm spacer to so it fits both

4)

I would hazard a guess that 'most' drivers are clueless about the operation of a car, they have been far too sanitised these days, as part of the driving test the applicant should have be taken to some random car in the car park, supplied by the test station (changed on a regular basis), they should then have to change a wheel or at least check the tyre pressure on each wheel (& adjust if appropriate), check the oil level, confirm the cooling system water level is at the appropriate level, fill up the windscreen fluid level. Only after they have done this should the practical take place.

what is it "let him that is perfect cast the first stone??"

 

[Deleted member 26715]

1) it could be that the crank is just loose.

2) 5000 miles isnt a vast amount for a BB

3)
83mm is very unusual.
73mm usual MTB
68mm usual road.
the standard SmBB52 has a 5mm spacer to so it fits both

4)

what is it "let him that is perfect cast the first stone??"

1. How do you tighten it up
2. Virtually all off road very little maintenance
3. 73mm
4. LIGAF if you wish to troll somebody go find somebody else. Seeking out an unrelated post just so you can post something appears to be an issue with your mental makeup,

 

[CXRAndy]

5000 miles is alot. Any way to measure a bottom bracket. Turn bike upside down. The measurement is the width of the bike frame from crank arm to crank arm

 

[Deleted member 26715]

5000 miles is alot. Any way to measure a bottom bracket. Turn bike upside down. The measurement is the width of the bike frame from crank arm to crank arm

That's 73mm found this one SHIMANO Bearing Shell BSA Bottom Bracket MTB Hollowtech II for Deore SM BB51 / BB52 https://amzn.eu/avWhKOQ but it mentions BSA thread is that normal for a modern EU bike?

 

[C R]

That's 73mm found this one SHIMANO Bearing Shell BSA Bottom Bracket MTB Hollowtech II for Deore SM BB51 / BB52 https://amzn.eu/avWhKOQ but it mentions BSA thread is that normal for a modern EU bike?

That's the most common thread, I thinkit is unlikely that you have anything else. You can find youtube videos on how to take the cranks out and remove and install the bb. You will need a tool to grab the cup, it will likely be tightish, and the drive side thread is left handed. Also it is a fine thread for the diameter of the bore, so easy to cross thread if you are not careful.

 

[T4tomo]

very little maintenance

do as say not as i do again then?

ooohh the irony.

 

[Ajax Bay]

@T4tomo - I get the gist of where you're coming from, and have not gone back stalking, but I suggest that BBs like the OP's cannot really benefit from 'maintenance' so the "irony" is not clear to me: what do you think @Phaeton could do, other than to seek a replacement (and on here make sure it was the right one). If this was lack of lubrication or brake/gear adjustment which has caused the deterioration then perhaps you might get traction.
As for car maintenance, whilst it's clearly impractical to require driving licence candidates to change a wheel, a good driving instructor will have included the other items (air/fluid levels) in one of the first lessons they give.
And a good (if capable) parent will demonstrate how to take a wheel off and replace it (though many cars now don't have spare wheels) and then get their offspring to actually do a 'remove and replace'. My father did way bitd, and all my children similarly benefitted.