A Few Maintenance Questions

[S6PNJ]

I was trying to fit a "Lidl special" bike computer to my bike (to use as a cadence meter and while it was inside, I thought I'd give it a quick once over. A quick note, the bike I'm playing with is an MTB and I know you don't usually have a cadence meter on one, but I use it for commuting and general road riding while away from my normal road bike (Trek SLR).

I noticed I've got about 1-2mm of play left to right in my bottom bracket and I'd like to remove it if possible. If the BB is knackered, then I'll fit a new one (but that's another question). My MTB is a 2009 GT Avalanche Expert and according to the spec sheet, the Crankset is a Shimano MC-542, however, when I bought it, it was fitted with SRAM Truvativ crank arms. There doesn't appear to be any brand name or makings on it other than "torque to" etc etc. I believe it's one of these. A Truvativ Howitzer.


My question is how do I get it out? Can I use one of these or do I need something different. Is one of these any better?

Assuming I get it all apart in one piece (so to speak - ie I don't bash it too much), once it is cleaned up will it simply go back in and tighten up and take out the play or is it a sealed unit and I need to replace it. If it needs replacing, how do I know what sort to fit? There are a whole myriad of them on Wiggle (and other places) and quite a few that are cheaper than a Truvativ Howitzer that I believe I already have.

I'm competent enough to get my hands dirty, no worries there, and if all else fails I've always got my LBS to get me out of the mire!

[mdavids]

Generally once a BB has a bit of play they are knackered and a new one is needed although some come with replaceable cartridge bearings and some can be "bodged" and the bearings knocked out and replaced.


The tools you linked to should be fine for removal, personally I'd go for the one with the handle on as you often need a good bit of leverage to get the cups loose. One side of the cup has a left hand thread and the other a right hand thread - make sure you know which is which or you'll be tightening instead of loosening. Take note of any spacers between the cup and the frame and which side they go on.

Park tools website is great for repair help:
http://www.parktool.com/blog/repair-help/external-...

If its definately a howitzer BB then you'll need to replace it with a howitzer type BB in order to be comaptible with your cranks. You couldn't replace it with a cheap shimano hollowtech 2 for instance even though they are both external BB's.

They seem quite pricey on wiggle/crc. A german bike shop called HS bike discount are cheap for BB's. Link:
http://www.bike-discount.de/shop/m328/k1212/truvat...

I'm not 100% but reckon you'll need the XR 68/73 51mm chainline.
http://www.bike-discount.de/shop/k1212/a7289/botto...

Suppose if you get it out you could take it into your LBS and double check before ordering

[Chicken Chaser]

Take of the pedal arm, and look for play in the bearing. Check to see if its running smoothly too. They are "Sealed" but you can carefully prise the top seal off the bearing, and if necessary clean it out and install fresh grease. All depends upon how worn the bearings are and how bad the bearing faces are.

[S6PNJ]

Thanks to both above. BB and BB spanner ordered from the German website along with a couple of other tools. Fingers crossed they arrive reasonably quickly and I can get the old one out without resorting to a BFH.

[S6PNJ]

Well my spares arrived from Germany today but I've now realised I need a crank puller. Bugger! So it's a few days wait for that to arrive now! Ah well, at least I can always get out on my road bike. The MTB will ahve to wait.

Will this tool get my Truvative crank arms off of my Howitzer crank?