BB size for 1998 Hardrock A1

[1979Andrew]

Hi, can anyone tell me what size bottom bracket is fitted to a 1998 Hardrock A1?

Thanks

Andy

 

[hamster]

No!

It depends on the chainset not the frame, apart from the obvious bit you can measure with a ruler (68 or 73mm shell).

 

[1979Andrew]

No!

It depends on the chainset not the frame, apart from the obvious bit you can measure with a ruler (68 or 73mm shell).

OK, thanks for getting back to me. Ill have a look at whats stamped on it.

 

[1979Andrew]

I removed the bottom bracket today and it measures 70mm with a 110mm spindle length.

The bb shell measures 74mm.

The cranks have 175 G-8 stamped on them.

So do i need a threaded 70x110mm bb?

 

[ishaw]

Based on the measurements you've stated, the BB shell will be 73mm, not 74. 70mm bbs are road Italian thread, you won't want one of those for sure.

If the length of your current BB axle is 110mm, then you are looking for a 73mm X 110 BB.

What make and model cranks are you using? The general rule is that the cranks are designed to work with a specific axle length for the cranks, if you confirm what you have, I'm sure people can advise on what you need.

 

[1979Andrew]

Based on the measurements you've stated, the BB shell will be 73mm, not 74. 70mm bbs are road Italian thread, you won't want one of those for sure.

If the length of your current BB axle is 110mm, then you are looking for a 73mm X 110 BB.

What make and model cranks are you using? The general rule is that the cranks are designed to work with a specific axle length for the cranks, if you confirm what you have, I'm sure people can advise on what you need.

The drive side crank says ST8 Forged 175 G-4
And the other crank says STL Forged 175 G-8

 

[CassidyAce]

Based on your 'Project Hardrock' thread, it's a Specialized Strongarm crank set (https://www.retrobike.co.uk/threads/project-hardrock.466903/post-3450988). 73mm x 110mm sounds right.

 

[1979Andrew]

Based on the measurements you've stated, the BB shell will be 73mm, not 74. 70mm bbs are road Italian thread, you won't want one of those for sure.

If the length of your current BB axle is 110mm, then you are looking for a 73mm X 110 BB.

What make and model cranks are you using? The general rule is that the cranks are designed to work with a specific axle length for the cranks, if you confirm what you have, I'm sure people can advise on what you need.

The driveside crank says ST8 Forged 175 G-4
And the other crank says STL Forged 175 G-8

Based on your 'Project Hardrock' thread, it's a Specialized Strongarm crank set (https://www.retrobike.co.uk/threads/project-hardrock.466903/post-3450988). 73mm x 110mm sounds right.

Thanks. I just got back from my local bike shop and the bike mechanic sold me a 73x110.5mm sqaure taper Oxford bottom bracket. I asked for a Shimano one but he said you would find it difficult to find one thats 73x110mm. He said the .5mm shouldn't be a problem you may need to adjust your deraliure. I can live with that.