Help needed - school me on replacing my Bottom Bracket

Bottom bracket on my Cannondale Synapse has broken.

Specific bike and spec is here:

Was ticking / clicking (worse than normal) for a short while beforehand (week or so) and I stupidly ignored this. Then it started to squeal and squeak extremely loudly mid-ride the other day. I lubricated with the only oil I had (3-in-1 oil … yeh I know !!) and it seemed ok for a short while but yesterday I tried some outdoor sprint intervals. Midway through the 2nd interval I heard a horrible crunching / creaking noise and it felt like it was ‘loose’ - it’s the only word I can come up with to describe the sensation through my feet. I did the rest of the ride (circa 20 miles loop home) at a slow easy pace and the pedalling felt ok-ish but with some squealing and creaking noises. On tentatively trying out any harder effort the noise and sensation reoccurred.

So I think I clearly need to replace / fix the BB :neutral_face:

Normally this would be a trip to my LBS (who re-greased and tightened it all up about 2 years ago when they fitted by Stages crank power meter) but they are closed and are only undertaking repairs via phone booking - a quick call to ask revealed they are now over a month away in terms of now only taking bookings for late May :flushed:

So I have decided to get stuck in and do the job myself …

My questions are:

  1. What tools do I need - the LBS said because Cannondale used the FSA BB30 bottom bracket I need a ‘special’ tool to remove it. I’m UK based so does anyone have a link to an on line place it can be obtained? I have a torque wrench and other ‘basic’ tools. Do I need a special tool for the bearings?

NB: I have decided I want to replace the entire thing rather than just some elements, as to me it makes sense to start again with a ‘clean plate’ so to speak, in case any part that may ‘look’ to be still ok is in fact nearly worn out.

  1. What other bits and bobs do I need to order to replace all the gubbins internally - plus is there a sensible ‘upgrade’ option I should reasonably consider whilst I’ve got the whole lot in pieces. What grease / replacement parts do people recommend?

  2. Can anyone recommend a good easy to follow on line tutorial for this type of job. I’m not bad at mechanical stuff once I’ve been shown what to do a couple of times - but I really have no idea where to begin at this stage.

Hoping to be able to get some on-line ordering done and have the bike back up and running next week -dependant on delivery times …

Thanks in advance

Sorry to say you ideally need a specific tool to remove the crankset before you can get to replace the bearings.

There are various hacks and workarounds but the right tool makes it easy and minimises the risk of damage.

It may be easier to try other bike shops. or use any other bearing from any other side that has the bearing code 6806.
Cannondale does sell “their” special tool but it is a box standard bb removal tool. just get the Park Tool one - if you stick with Cannondale you’ll need it often.
To remove the crank you loosen the screw on the non drive side untill it comes off. To remove the crankarm you will need a Shimano crankarm removal tool and a rod just a bit shorter than the bb shell width - ( there is also a special Cannondale tool for this if you can find it) . Just do it like in this video:
Take grease on metal contact surfaces that is waterproof or use a very light locktight on the bb shell.

Take of your crank and then just do what they do here

Here you go. Nice simple process.

Video not embedding

Sigh. Lots of special tools that I am lucky enough to get access to at work. Might be worth the $$$ if you need to do this often.

Thanks all - this is super helpful
Much appreciated


With a fleet of cannondales I am a pro at this;
Cannondale specific hollowgram crank tool ($30 talk to your cannondale LBS dealer) - worth it. There are work arounds but just get these two small pieces and make your life easier.
Park tool BB press - or any press system will do, use the cups from BB puller below
Rubber mallet
Park Tool BB Puller - - you need this, dont try without it
Loctite - green stuff not blue or red

Takes about 40min the first time, 20min once you know what you are doing.
Biggest thing is making sure that you clean the surfaces and allow loctite 24hrs to cure before you reinstall cranks,

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I would advise against using just any 6806 bearing, as you tend to get cheap low quality bearings which do not last long. I would suggest getting high quality steel bearings - NTN, SKF, FAG are good companies for this. I have done all my BB overhauls using a bottom bracket bearing press bought from ebay.

NTN bearings:

Bearing press:

Try and use the right tool for the job, avoid using hammers at much as poss.