Can you change the rings on a standard road Si chainset 39/53 to 34/50? Or do you need to buy a new spider?

Compact rings have a different bolt circle diamater, thus cannot be used on a standard crank. If the spider is replaceable, then I guess you could do that. It may be easiest to just buy a comact SI crank on ebay and re sell the one you have.

if you talking about hollowgram (std or SL0 all you need to do is buy a new spider and rings and swap them out via a lockring on the back of the drive-side arm. If yoiu talking about the carbons you have to replace the whole crank. This is one the stregnths of the hollwgram setup.

The spider should be $70-$80 from your cannondale dealer.

Starnut

Thanks Starnut, yes it's the Hollowgram ones. Not definitely changing just wanted to know if could be changed first

I use 50/38 on normal spider.
it's a "fake" compact, but works quite ok... :D

Standard star = 130mm

Compact star = 110mm

Same 5 bolt pattern.
Cannondale's website has a pdf (http://www.cannondale.com/tech_center/bikes/road_bike.html) version of the Hollowgram crankset maintenance manual.

I'm in the process to place an order for Si crank with compact setup 50/34, I hope Cannondale has it instock.

Did anyone end up getting a new spider? Im in the process of getting new prices for a 130mm spider.

No more than $100 for the 50/39 spider.

Thanks. Are there any online shops that sell spiders that will work with the cannondale crank set up or can they only be purchased through cannondale

Rob,

Unless it's the new FSA BB30 spidey I don't think other MFG will work with Si crank, beside stay with OEM part that way you know it will works.

Just got told new spider would be $130.. Bit more than i thought it would be does anyone have any other suggestions/ other spiders that would work with my SL 08 cranks?

that is a bit high according to Starnut the compact rign only cost $75, send him a Pm and see if he can get you a good deal.

That price is with chain rings as well. The spider alone should be ~$75.

Starnut

Rob,

why don't you hook up with Starnut for your spare parts ?