Fifty Plus (50+) - Trek 800 bb - what direction to take out?
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11-08-08, 12:21 PM
I just bought an old Trek 800 that I'm doing a lot of repairs on to make into my semi-regular ride to work. I'm kind of enjoying learning how to work on it, and have begun accumulating bike tools.
But now I've encountered a little snag. I need to rebuild or replace the bottom bracket. I got the left side apart easily and pulled out the ball bearings and race, but the shaft won't come out. So I assume I have to take apart the right side too. Does anyone know what direction to turn the spline thing that holds it in? It doesn't appear rusty but I can't budge it. The tool I bought (made by Park) fits, but not snugly. When I apply real torque it sometimes slips out, and without knowing what direction I should really be going in, I'm afraid to really apply a lot of torque, because I'm going to end up stripping the threads or destroying the notches in the retainer.
As a last resort I can just machine it out with a dremel tool until its thin enough to split and break out, and then just buy everything new, but I would really like to avoid that if possible.
Any advise from anyone would really be appreciated.
11-08-08, 01:32 PM
You have just asked a question that without attempting to take one out- I cannot answer. In fact- even when I attempt to take one out- I normally get it wrong. Whichever way it is- If you turn on the tool and it doesn't budge- try the other way. And for those that are in really tight- I hold the tool in with a G Clamp. (Woodworking type)
Unless you have the old type of BB and although I have the tools to turn the nut- I normally Use a Drift and hammer to get the thing moving. Don't care if I damage it as I will replace it with the new sealed bottom bracket.
11-08-08, 01:34 PM
The Drive Side is a left hand thread, or opposite the NDS.
Is this a cup & cone type or cartridge?
IF yhe former, you can find a spindle here-
and cups here-
That spindle worked on my 1991 820.
11-08-08, 01:43 PM
Here is a way to do it if you are a beginner with minimum tools. Keep the wheels attached to the frame and fork so you can get leverage without the frame jumping all around. Stand on the other side of the bike from the side of the bottom bracket that you are removing. Lean over the bike and hold it down with your stomach (there are advantages to being slightly rotund). Hold (pull toward you hard actually) the bottom bracket tool with your left hand as this will keep it from popping out away from you. Set the wrench so that you are pulling up with the right hand in the proper rotational direction. The longer the wrench (I use a 250 ft/lb beam style tork wrench about 2 1/2 feet long), the more control you will have over the pull.
Right hand up.....Left hand toward you.....Body weight down. This is how to herd bottom bracket cats.
Pushing down toward the floor with any wrench is a disaster waiting to happen because the most stubbron fastiners like to come loose at once.
11-08-08, 02:13 PM
The trick is holding the Park bottom bracket tool flush against the splines. Couple of tricks:
1. Find a bolt with the right thread. Use it to hold your BB tool against the splines like we used to do with freewheel tools.
2. Chuck your BB tool upright in a sturdy bench vise. Thread your bike onto it (a helper would be good). Remembering that the right side is a left hand thread figure which way to twist the bike frame. (Another freewheel trick)
3. Get a genuine Shimano BB tool. It sits much closer to the bike frame so it doesn't tip the splines nearly as easily.
11-08-08, 03:02 PM
For an English threaded BB, which is what your Trek would have, the right side (drive side) thread is a left-hand thread, which tightens counter-clockwise and remove clockwise.
When I tried to pull the bb from my Trek520, it refused every attempt so eventually I took it to the lbs. The mechanic started with his standard tool and worked up. Eventually, he used a tool with a 2 metre extension welded to the handle and only just managed to start it. He said afterwards he'd never been defeated by a bb but this was starting to look like the one.
Soooo, try the suggestions above but don't be too proud to go to your lbs.
11-08-08, 07:33 PM
Thanks! I had thought of the g-clamp before seeing your reply but was still afraid to apply any torque to get it out. Your answer boosted my confidence and I got the job done. Tomorrow I'll be riding again.
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