Hi... I am turning my Cannondale into a single speed and I really like the look of the 6700 / 6750 grey crankset...

I am going to order up the 6750 Compact crankset because it has the 50t outer ring and use it with a single rear cog properly spaced on a shimano 9/10 speed freehub. (I will also be getting a chain tensioner...)

Here are some questions I have....

1. Can I run that Ultegra 6750 crankset (Pictured Below) with just the outer ring? If so, what will I need?

2. With the 50 tooth front ring I assume I will need about a 19-20 tooth cog on the back... will I have a problem putting a large cog like that so far spaced out for the chain line? (I am aware that one limit may be if it hits the rear stay, but I'm more concerned about load on the freehub)

3. For the rear cog, do I just take a couple old cassettes apart and use all the spacers with the particular cog I want then throw on the lock ring?

4. What chin tensioner does everybody recommend? I don't want to buy a $150 one but I don't want to waste my time with a crummy $10-20 one that sucks.... I hear that both shimano ans surly make a good one but which model and are they both fully adjustable??

Thanks!
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