Questions on using a road-double crankset
 

I'm looking to down-grade on my crankset to save money and reduce chances of theft. Quality road-double cranksets go for very little on Ebay and craigslist everyday. I was wondering if people here were using this strategy and how they were liking it? Also, what is the method for using them? Running the ring on the outside?

And finally, what cranksets are recommended? I've been looking at Ultegra 6500 sets.

Thanks

You just use them like a normal crank with it's corresponding bottom bracket spindle type and dimensions; road cranks are 130 BCD; so you would be able to use a traditional fixed oriented chainring if you want.
For the chainring you can go both ways, mounting the chainring inside or outside; it depends on a couple of factors but primarily, you aim for a straight chainline.
Older sram force and rival go for really cheap.

Most budget "Track cranks" are road doubles with only one ring, so no problem there.However, I found that a shorter BB is usually needed.I've had good results with older square taper cranks(like sakae cx or sugino vp) running the ring on the outside using 103mm sugino BBs.

Most middle line and lower end SSFG cranks sets are really double road cranks with one of the chainrings removed and shorter chainring bolts. The only difference is in the bottom bracket spindle length, which is chosen to provide a straight chainline. In fact, I converted a Sugino RD2 single speed crankset back into a geared double for use on a different bike.

So figuring out the correct spindle length for a given set of cranks to get a 42mm chainline would be mostly trial and error?

You may have a difficult time with an Ultegra 6500, because it has its own proprietary BB that is not available in the correct length for single chainring duty. If you place the chainring on the inside, then it might hit the chainstay if it is a larger size. I think you are better off just looking for a used lower end SSFG crankset and BB.

On a road double crank, the bottom bracket spindle aims to put the chain directly between the two rings. In doing so, the chainline is off by 1.5mm on either ring. Typically, you can use the same bottom bracket spindle intended for a double setup, or you can subtract 1-2mm and put the chainring on the outside of the crank spider.

For example, my old Shimano 105 road double crankset requires a 107mm BB spindle. A 103mm spindle would bring both crank arms 2mm inboard, which would likely give me a near perfect chainline if the chainring is on the outside.

older shimano 600 and you golden.

I've used 6500 before, easily doable with the correct bb size.

6600 is tricky to pull off.

68x109.5 will be the size you will need for the bb.

That is the Octalink BB size for a double crankset. How is that going to get the correct chainline for single use ?

When you put the chainring on the crankarms, use the inside instead of the outside, works like a charm.

http://www.benscycle.net/index.php?m...0&currency=USD

That said, I like square tapered cranks better.

It's still going to be off, only this time to the inside. Also, there's a good chance if you use a larger chainring that it will hit the chainstay. You may have had success in your case, but it was not an ideal setup. If the OP already had the road cranks, then I could understand going about this way, but it makes more sense to get JIS square taper cranks, where there are many different BB widths to choose from.

Had a 50 tooth on the inside, did not hit the frame(even under hard pedaling) and was silent.

That said, I agree with the square taper cranks.

What length spindle?

Depends on the model. Sheldon has a partial list.

More photos of the purple bridgestone?

Pedals have since been changed to SPD / cage type so I can ride with either SPD or regular shoes.

I'm having a little trouble with it. Can anyone find a way to figure out the correct spindle length to get a 42mm chainline (approx.) with Shimano 600 cranks? Would I just run the specified spindle on Sheldon's site, 113mm, and get a 43.5mm chainline, or should I try to go for a shorter spindle (if possible).

If you want the correct chainline, find a 110mm spindle.

Yesssssssss.

This would be my road double of choice if I were to go that direction. I actually bought a pair of tricolor 600's awhile back to use on a build but found a better deal on a track crankset and sold them. Suhweet cranks, though.

i have been using a campy square taper road crank for years without issue. i use it with the recommended 111mm spindle, a miche 1/8" ring on the outer position, and a 1mm spacer behind the cog on the rear wheel. chainline is perfect, and there is still plenty of cog/hub thread contact even with the spacer eating 1mm of availability.

mildly on topic: using a pair of shimano 600 doubles for a junk bike. i put them on a 107 bb (i believe the original was 119, according to velobase); i'm just using what i have sitting around. the big problem is this: the non drive side crank arm is a whole lot closer to the chainstay than the drive side arm. to my knowledge, un57s are symmetrical, so what gives? anyone have a reason/solution?

^^^I'm curious about that too

Is the bottom bracket spindle inside correctly? The spindle has one tip longer than the other for your drive side crank.

you guys are all wrong!
road cranks (like shimano 600) + 103mm bb + chainring on outside (better for aesthetics) = 42mm chainline.

http://www.universalcycles.com/shopp...s.php?id=16123