mtbfreak

So do I ................SNAP you guys should try two a breast...

cool, I'm taking my boy there in a few hours time..will look for the pot of gold..

Me too, and I suppose that I could have just said that, but that tool is worth another look ;o)

lol...good one

realy cool...happy laps.

Nice...one question though... Can you get to the outermost gears without the chain rubbing on the guide? or what is the limit?

Do you often stand and climb? Nope Do you clean the WHOLE drivetrain properly all the time? Yep, two brushes, and the elastic part of old undies ;o) What chain are you using? SRAM 971 Maybe you had a Friday chain... or a Monday chain

ok, thanks. So the moral of the story is that when the chain gets to 12 1/16th" the cassette is most likely on it's last...and that I need to save all my money for a new cluster and chain every few months...

That's what I thought, but if you look closely at the close up, you can see the metal of the teeth folded back. This is especially prevalant on the middle section of the cluster (my favorite gears) i.e. 17, 20 & 23...and that's where it skips the worst under climbing load

mtbfreak2009-06-26 12:25:00

I read through this thread "Chain Replacement on MTB" https://www.bikehub.co.za/forum_posts.asp?TID=51384&KW=chain and decided to buy a new chain and try the rotation of 2 chains. I currently have 450km (offroad only) on the chain (SRAM 971) and Cluster (SRAM PG980). I thought that this is a good time to try this as the current chain should not be close to the 12 1/8" mark right now (as detailed in this thread: Everything about chains: https://www.bikehub.co.za/forum_posts.asp?TID=43797&KW=everything+about+chains&PID=688598#688598 , and even if the current chain is ready to be replaced, I'll perform the rotation using two new chains, because the cluster should be fine after ony 450km. So I bought a new chain and after installation took it for a Majik ride. The chain started to skip on the first ascent, and as no adjustment could be made to resolve the skipping, lead me to inspect the cluster closely. The cluster now had some nice indentations on the teeth and is basically stuffed. Close up of the offending teeth: I measured the old chain with a ParkTool CC3 chain checker and the 0,75% wear indicator just fit (a really tight fit;), I measured with a ruler over 24 teeth: 306.8mm. I measured with a vernier over 12 teeth: 153,05mm; which equates to 306,10 over 24 teeth. ToolMeasurement# linksMeasurement extrapolated to 24 linksBase (new) [Acc to diagram]304,8024304,80Base (0,52% wear i.e. 12 1/16")306,3924306,39Base (1,04% wear i.e. 12 1/8")307,9824307,98 ParkTool CC3 (new)127,0010304,80ParkTool CC3 (0,75% wear)127,9510307,09ParkTool CC3 (1% wear)128,2710307,85 Actual Measurement Vernier153,0512306,10Ruler 24306,80 My measurement using 3 methods, yielded an acceptable time to replace the chain and cluster wear should not have been significant. However my cluster is clearly damaged and after 450km, I dont believe this should have happenned. By my reckoning, I should have had a minimum of 0,89mm chain wear remaining before cluster damage (307,98-307,09). I have treated my chain well, cleaned at least every second ride, and if it was muddy, it was cleaned after every ride (sometimes with parafin, most times with clean green and a brush) before I cleaned myself. I understand that the extra weight I carry causes accelerated wear, but the cluster wear is the concern. I have since changed my cluster to match the new chain (15km used on old cluster). A new chain will follow for the first rotation. Was the first cluster of inferior quality? Was the cluster damaged by the skill level of the rider? Can I expect the same to happen in the future? Is the measurement of 12 1/16" still valid or should this be shorter? mtbfreak2009-06-26 12:33:57

chain tensioner, spacers for rear cog and UST tires...

you only use them if you want to service your hubs, i.e. clean hubs, change grease and or bearings...whether you need them or not is debateable...

You mean 16/17 May and have the fork workshop on the afternoon of 15 May, with cold Windhoek lagers after?