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Old 09-29-11, 08:28 AM   #1
Ranger63
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Velo Oranges Polyvlant Compact Double

Need some feedback on this.
Wanting to retrofit my 91 Paramount for hill rides, the 110/74 Polyvlant from Velo Orange seemed the perfect (and cheapest) fit.
Then I saw the 118mm BB requirement.
It weems to me this would render the oem double front derailleur unuseable as well as throw a curve in the chain deflection (The OEM spacing of the 7 cog rear is 126)creating a whole host of issues.
The gist I get is the Polyvlant compact double was origionally a triple that VO converted to a double (hence the bash guard out front and the disclaimer about the 46t being a middle chainring vs outer)
Am I correct in my eval. that this 'compact' would require a triple fd and a ton of tweaking with the chainline and downtube shifter (this is a sis setup)
Thanks
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Old 09-29-11, 08:38 AM   #2
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You're only going to be shifting over two rings, though, and the difference is only 16 teeth. A FD designed for a double crankset should work fine. A double with a "pants guard" is nothing new.

I just purchased one of these for a build and will be using an Ultegra FD-6500 for a double. I don't expect to have any shifting issues.
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Old 09-29-11, 09:06 AM   #3
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You are confusing two independent issues and making this much harder than it really is.

Buy the crankset.
Buy the correct 118mm BB

Install
Done.

Now if you try to install the new crank on your old (and it's not 118mm+/- a few mm) BB, then you'll open up some of the issues you're worried about.
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Old 09-29-11, 09:11 AM   #4
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Don't let a long spindle throw you off. All cranksets are designed to give a correct chainline with their mating spindle. Different cranksets have varying amounts of offset between where they fit the spindle and the chainring location, and so take different length spindles to yield the target chainline.
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