[canuck88]

Hi all -

I'm running into a problem fitting a new crank and BB onto my '03 Giant XTC1... Giant says it needs a 68x113 (shimano octalink v2 with '03 LX, XT, or XTR crankset) to maintain stock chainline... but I've read so much about the M572 LX cranks needing 121mm for the ES-51 and 118mm for the ES-71 to be at 47.5mm chainline (or 46mm with the ES-71)...

Who's right? How much difference does the frame make?

If I go with the ES-51 BB should I be buying 113mm (like Giant says), 121mm (like everyone on the forums says), or 118mm for a happy medium??

Scott

 

[canuck88]

Nobody has any advice?

 

[RhinofromWA]

Nobody has any advice?

My head is still spinning from that.....

No good advice....but,

You are talking to a guy who has a concentric pivot and needs a 80+ shell and a 130+ spindle. Until now I have always run 3pc BMX style cranks.

You are talking about approx 3/10 of an inche overall width difference. If spaced evenly that is half of that on the chain line.....not much (about 15/100 of an inch.

Why again is it important to go 122? To clear something? Of so go 15/100th's off of the original chain line.

Do I care what you do? Not really, I do wish you luck because I am dealing with similiar issues.

 

[MikeD]

The NEW STYLE (2004) LX cranks need that 121 BB to get a normal chainline. I read this somewhere, but the jackass at the local shop insisted I was a moron and the cranks needed a standard 113mm ES71 BB.

Well, turns out that's not right. The new BB (ES51 or whatever) is needed for a standard chainline on an XC bike...it's the equivalent of a 113 on the old LX cranks. When mated to a 113mm octalink BB, the granny ring will bottom out on your BB shell long before your crank bolt is all the way in.

MD