How to Tighten, Remove or Install a Shimano Hollowtech Bottom Bracket

When it comes to adjusting bottom brackets, it always frustrates me that a special tool is needed. These special tools are invariably of no use on any other job and sit in the bottom of the tool box until the next time you need to tighten a bottom bracket. At least one that takes this specific tool. Having recently purchased a mountain bike and discovered the bracket has loosened itself, I was not exactly shocked to discover that the bottom bracket tools in my tool box would not fit this particular bb – in this case, a Shimano HollowTech II BB.

So – a new tool was needed. Two new tools in fact – one to remove the dust cap on the end of the bracket and one to remove the bb itself. Great – another $20 down the drain. Well – in this case 27 Euros. Those of you living in the US are lucky enough to be able to buy the Park Tool Bottom Bracket Tool – the BBT-9C for less than $17, but here in Europe, not so cheap, because the Government Inc does not let Amazon get away with tax free sales and squeezes their 19.6% sales tax from any online sale.

Although, I gather that the American Government Inc is in the process of starting to squeeze as well – so perhaps by the time you read this, they will have taxed Amazon out of existence? Who knows – in any case – this is the tool you will absolutely have to buy to tighten, remove and install Shimano Hollowtech II bottom brackets. Don’t bother buying a Shimano branded tool and don’t pay more than $17 for it. Trust me – even if you weigh as much as I do – you are not going to need it very often unless you are a bike mechanic.

You need this to adjust a Shimano Hollowtech Bottom Bracket:


You can buy them on ebay, but they are usually cheaper at Amazon:

How to adjust a Shimano Hollowtech Bottom Bracket

First, loosen the bolts holding the non-drive side crank and remove the outer dust cap using the little plastic tool supplied with the big tool. This takes about 12 milliseconds.

Loosen and remove the dust cap:


Remove the cranks:




Now tighten the bb using the special tool. I usually go with hand tight plus a quarter of a turn. In this case, I removed and regreased seeing as it was the first time I had tightened it, but this is unnecessary if you know it is well greased.

Tighten alternately:

2658594_f1024 2658598_f1024 2658601_f1024



These bottom brackets are marked clearly which way they need to be tightened, and this tool will also work on not only a Shimano Hollowtech II, but Campagnolo Ulta-Torque, Race Face, FSA, SRAM, Truvativ, Chris King, and many other external bearing crank set bottom brackets. One end of the BBT-9 engages the 16 notches of the bottom bracket cups. The other end of the tool engages the 8 internal splines of the dust cap. The BBT-9 also fits the rotor disc lockrings using 16 external notches.

These are all the tools needed to complete this job: