Bicycle Mechanics - Suntour Sprint 9000 chain wrap and cog sizes....

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Binxsy
12-08-09, 09:37 PM
I found someone selling the set of this, but I am worried about my chain wrap cog size etc...

My maximum rear cog is 28 and the sprint RD is rated for 23 for the maximum.

In the front the difference is 14 and the suntour fd recommends 13
For the back one the difference is 15 the sprint one is 13.

Is this possible to do? I have read sheldon browns blurb about chain wrap (http://www.sheldonbrown.com/gloss_ca-g.html#capacity) and how this this number they come up for rating derailleurs is less than actually possible. And I am fairly confident that this will work. But a second opinion is always nice.


So any thoughts? Or should I just spend about 40$ or so more for ultrega derailleur set.


DMF
12-10-09, 10:15 AM
I can't figure out what it is you're trying to do.

New Posters - please READ THIS (http://www.bikeforums.net/showthread.php?t=338432)

operator
12-10-09, 10:30 AM
I can't figure out what it is you're trying to do.

New Posters - please READ THIS (http://www.bikeforums.net/showthread.php?t=338432)

Seriously DMF...

His post is quite clear, he wants to run a derailleur rated for a 23t max cog on a drivetrain that has a 28t. I'm going to say, even conservatively that it's not going to work.


DMF
12-10-09, 10:46 AM
That is so obvious I doubted it was his question. But if it is, I agree 100% with your answer.


Binxsy, you don't have to buy the Ultegra, but the Suntour set won't work.

Binxsy
12-10-09, 07:30 PM
I figured it out and picked up a ultegra 6600 sl front and rear for about 90 buck new.

Anyway it seemed close enough, and after I posted this thread I soon realized the error in my ways.

My original thinking in this was that the maximum chain wrap with the suntours was 26. And I read that this number can be flexed a bit My chain wrap is 29 as I stated before, so I figured it was close enough.