Cyclocross - Changing the front cogs on 08 Felt F1X

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cwiz
05-21-10, 04:08 PM
I was looking at different road bikes and noticed they had larger large cogs and smaller small cogs. it got me thinking about my commute and how changing my front cogs might help a lot.

Basically my ride to work is 90% downhill, 5.5 miles going from 830ft above sea level to 370ft. I totally max out in top gear at the top of the big hill and coast for about 3 miles, not that i'm complainin but top speed is ~38mph. On the way home, i have to dudge up the same hill avg speed of like 7mph in my lowest gear and i'm workin.

Can i swap out my 36/46 front cogs for 34/50 like those found on the 2010 Felt Z5. I guess the even higher end Felts have a 52 and 53 tooth large gear. my large cog is 110mm and the crank says 110mm on it so i think i'm going to run into some compatability issues here. is it really just a swap the gears job or would I need to swap out the entire crank set.

I have about 860miles on my bike right now. am i going to run into chain wear issues with new teeth on the front and old teeth on the back cogs?

thanks for helpin a noob out.


barturtle
05-21-10, 04:32 PM
You'll likely need a new chain, as the bigger chainring in the front would likely be more than your stock chain length is able to handle.

Other than that, you should be fine. Just swap out the rings, fit a new chain and go.

cwiz
05-21-10, 04:43 PM
i like your can do attitude, barturtle! we'll see how it works


barturtle
05-21-10, 05:05 PM
Okay, a bit more: I checked out your specs before posting the first, rr der is fine with the new rings. But, you'll likely have to more the fr der up a bit to clear the new rings.

cwiz
05-21-10, 05:09 PM
hey, thanks, ya that tweeking the front derail up was expected, no biggie. i just dont know what the different bolt patterns are for different cogs like between shimano and sram and all the variations there in. just gotta do more research

scattered73
05-22-10, 12:35 AM
you shoulld be fine with some minor adjustment and new chain, I recently did the oposite of you went from 50/34 to a 36/46. I bought the fsa rings I would recommend making sure that you are at least close to the correct size (meaning # of gears). I cheaped out on the small chain ring first and bought a 8 speed version for my 10 speed drivetrain. It worked but got noisy under certain conditions since replacing with correct 10 speed small ring has been great.