trail-rider

When removing and installing a square taper (or splined for that matter) bottom bracket, how do you keep the bottom bracket tool from slipping out when applying a lot of force.

The park tool website, https://www.parktool.com/repair/readhowto.asp?id=94, suggests using a wheel skewer, but my Shimano square taper bottom braket is not hollow all the way through so this won't work. I've tried laying the bike on its side and it is still prone to slipping.

I've also thought about using a c-clamp to keep the tool on. Any suggestions? Thanks!

J B Bell

The technique the shop that I brought my bike to uses is to put the BB remove in a table vise, lay the bike in it, and use the frame as a lever. Apparently this is tried & true.

C-clamp makes sense too, I thought about that myself.

AEO

lay it on the floor
lean on top of the tool while turning the BB tool.

zjk

One guy actually showed me a handy way to do it the other day. You need a little bit longer crank bolt and you just screw the crank bolt on right through the bb tool into the bottom bracket. It keeps the tool on tight while it stays very small and descreet

MarvelousMark

I stick a big long metal pipe over the handle of the socket wrench to give me maximum leverage. Hold the teeth in with one hand, and pull on the pipe. Comes right out.

sooprvylyn

+1 this is the best way- works well for freewheel removal too

trail-rider

Thanks for the help! I like the idea of using a longer crank bolt. I use the Park BBT-22 and it has a 3/8" drive so I imagine I can just slide the longer bolt through the tool and maybe use a washer between the bolt head and tool.

Doing it this way I will have to use a 32mm? wrench (or adjustable wrench) with the tool rather than a socket wrench, but I can't afford a torque wrench right now anyway!

zzyzx_xyzzy

Less awkward than a c-clamp is to hold the remover tool on using a washer and a long bolt (same threading as a crank bolt) into the spindle. If the spindle is hollow you can also use a wheel skewer. Combine this with the vise technique as seen on Park's site:

https://www.parktool.com/repair/readhowto.asp?id=94

trail-rider

I'm not close to my bike so I have trouble visualizing this but when removing the BB cup using a longer crank bolt it seems like you might run the risk of stripping the crank bolt threads because the bolt keeping the tool on is opposing the unthreading of the cup. Does this sound reasonable? I suppose you could just bolt the tool on fairly lightly so it doesn't put as much stress on the threads, but then you wouldn't get as much force keeping the tool on.

Ed Holland

On the chainwheel side they'll move together, if it's a cartridge bb. On the non drive side, there's little risk of stripping, as you can feel when the tool begin to push against the bolt. Things don't have to be tight to hold the tool in place, so you can leave a little slack, say 1/2 turn and keep "inching" the tool out, loosening the bolt a bit etc., etc., until things are loose enough that you dont need the bolt. Just make sure the bolt has 4 or more turns of engagement in the spindle.

Cheers,

Ed

HillRider

FYI, the threading on crank clamp bolts is M8x1.0 mm, not the more common M8x1.25. You will need a bolt about 40 or 50 mm long. I was able to find a 50 mm bolt with the proper thread at my local hardware store but they aren't that common so a specialty fastener shop may be a better bet.

operator

Pedros makes this tool specifically for that application:



You don't risk stripping any splines with this method.

elcraft

I had the same problem. I had an older version of the Park tool that had no Hexagonal flats on it. In order to secure it, one would think to use an extra long bolt and thread it into the spindle, using the threading for the crank bolt. But with the older version of the tool, the 3/8" drive unit couldn't be installed with the bolt protruding through the tool! I ended up buying the newer version of the Park tool that has a 1" hexgonal wrench surfaces, in addition to the 3/8"drive socket. I use the afore mentioned extra long crank bolt (with a greased washer)to secure the tool into the bottom bracket splining, and then I can slip a 1" deep well socket over the secured BB tool (and protruding bolt head)and not have the tool slip out under load. It is annoying that I had to buy TWO park tools to do one job.....