Mountain Biking - Possible repair? Wobbly front block

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Dazza
06-06-03, 05:26 PM
On my current MTB , my front block (cog, gear whatever) is slightly out of line, as the pedals go around, and you look down, there is a slight sideways movement during each turn, but its not like its loose, as it moves at the same place through each pedal stroke.

Am i in need of a new front block? I really dont fancy spending a lot of money, so if i do, the MTB will probably be out of action for a fair while, until i get my road kit completed.

Cheers for the help, and sorry if i sounded a bit vague. :rolleyes:

Cheers :beer:


a2psyklnut
06-06-03, 05:56 PM
Block? What's that? Do you mean the bottom bracket? Where the cranks attach?

If so, they're not horribly expensive, and relatively easy to swap out. Problem being you need a couple specific specialty tools. You'll need a crank puller and a bottom bracket puller. Each are about $15 mail order and you should consider buying them if you continue as a cyclist. BB's wear out regularly and you'll be changing many out through the years. Plus, a decent BB is about $25 mail order, so for the cost of having your LBS do it, you can get the part and the tools and the experience. However, if you a mechanically declined, leave it to the LBS as you can screw it up!

Plus, you've got to find out which size you currently have. This usually requires an e-mail to the Manuf. or some internet searching. Of course if you have a bb remover tool, you can take yours out and read it where it's stamped onto the housing. That's assuming you already have the tool and are not buying it along with the replacement BB.

If you decide to indulge yourself in this endeavor, send me a PM, and I'll talk you through it!

L8R

RussellM
06-06-03, 06:59 PM
is it the bottom bracket thats messed up? it sounds more like the cranks are messed up. Perhaps you just bent your big ring on a log or somthing? if this is the case you will need the crank puller, but not the BB tool. And a new crank.


Jim311
06-06-03, 08:08 PM
Bash the chainrings back in with a rock, hammer, whatever. They'll be fine.

Rev.Chuck
06-06-03, 08:53 PM
Look close to see if just one chainring is out of alignment or all three. If it is just the big ring you can tap it with a hammer or grab it with an adjustable wrench and bend it back. If all three are out of line you need to whack the spider(where the rings bolt on) with a hammer to bring them back in line.

Dazza
06-07-03, 11:39 AM
Sorry for confusing you guys :p , its the front gear set, cassette, ring (as in you have two rings on an 18 speed, and three rings on a 27 speed)

Every rotation of the pedal, gives a slight sideways movement, causing the chain to rub on the fron derailer, making a clicking sound.

Sounds like all it needs is a good slap to get it into line.

Cheers for the help guys :beer:

Jim311
06-07-03, 04:55 PM
I took mine off and put it flat on the concrete floor of my garage, and grabbed a BFH to pound it straight. Worked fine... still using those rings.

Dazza
06-08-03, 06:07 AM
Cheers for the help :beer: