Cyclocross Magazine

Cyclocross Community, Forums, Classifieds, Photos and Videos

Hi there. I usually do CrossCountry in my Mtb and a lot of urban cycling (i like alleycats), and I am building my first CX bike (moderate budget) and I have some questions about the groupset...
I am buying the parts from diferent sellers (ebay), for now I have:
- Gallardo Kong frame (bamboo frame)
- Avid BB7 disk brakes.
- Picasia carbon fork (good price)
- shimano 105 FD 5700
- shimano 105 shifters 5700 (2x10)

I am going to buy:
- shimano slx or xt 9 speed rear derailleur
- shimano 12-30 (road) or 11-32 (mtb) cassette

So.... I do not know what crankset to buy.... Maybe a shimano 105 50-34... Or should I go with a more specific cranckset for CX?
Should I buy a rear derailleur like a 105 or tiagra short cage and a 11-28 cassette?

I am totally new to CX and here in Bogotá it is a new sport... Very rare....

Thanks for your opinion!

Views: 2214

Reply to This

Replies to This Discussion

Actually the CX here is new... The fan page has only 140 fans... People confuse the cyclocross with bicicross (bmx)... But anyway...
With some friends we are doing a team... And looking for places where to practice and have some fun... Maybe start doing some races and see who will be into the CX local scene.
I was thinking to use the bike to do some road cycling... So maybe I will go with a 50-42 chainrings and a 11-32 cassette... Only use the 42 for CX and 50-42 for road... Or 50-34.....


Personally, I find a 42 too tall a gear for CX if your only ring.  The 50 will be pretty useless offroad.  Unless you are a super strong rider, once you get offroad, you might find the 42 holding you back.  I ride a 1X set up with a 38 and 11-26 or 12-27 cassette.  Rarely do I get past mid-cassette on most courses.  As Chad recommended, different rings you can swap out might be your best bet.  So a 50/34 or 50/36 for the road and a 42 ring to switch with the 50 for CX/offroad fun. 

I am looking for a medium range crankset...
So... I saw the FSA Gossamer 50-34 (compact) for $90 and the Shimano 105 50-34 (compact) for $100... Any other options? What about the quality of those cranksets


I have a Praxis Turn M30 172.5 crank and corresponding BB for a BB30 frame.  This crank is neat bc it fits nearly every style frame/bb on the market by using the proper BB.  It has 36/52 rings mounted but I could mount 36/46 rings if you'd like.  I would take $200 for the crank with 36/46 rings (slightly used rings) and $50 for the BB30 bb if you need it.  I also have Industry Nine i25tl Disc wheels (used since August) and a set of Roval Carbon Tubular CL 40's with Clement MXP tires (14 total rides) mounted if you need training wheels or race wheels (or both).  =)

Please let me know if you have any questions and good luck in your project.

After searching the web and local shops i decide to buy a shimano 105-5600 crankset with 50-39 chainrings, and the best... $55 brand new... A friend give a 42 chainring, More options to try.

Thanks to all of you for your advise and help.

105 5700 shifters are indexed for 10 speed and will not work properly with a 9 speed RD. Running a double front setup you'll have no chain drop issues using a 105 RD, so I would suggest that instead of the SLX or XT. 

If you're riding offroad with this bike, go 46-36, or if you're more powerful maybe 48-36. 

If you're going to be on harder gravel and pavement, the 50-34 should do fine. 

I've been using an Ultegra 11-speed setup but with a single SRAM 42t in the front (and therefore no front derailleur) and 11-32 in the back, and it's perfect for anything I'm doing with my cross bike. I'll never need more power than 42x11 can give me, and with the SRAM narrow-wide chainring, I haven't dropped a chain yet even when riding through sloppy mud. 

Good luck!

Sorry, this is just flat out not true. If you have questions, a quick search of Sheldon Brown's well regarded site will reveal that 10s road Shimano shifters work perfectly with 9s Shimano MTB derailleurs. The only potential issue is with RapidRise derailleurs, which are reversed in cable pull direction and result in the opposite lever blade upshifting vs downshifting.
The shifter I have installed work really good it is a 9 speed Shimano XT... I have been using the bicycle for road and a some CX.....
These are the photos just when I build the bike...

I have been very happy with my budget 1x9 groupset. I use a top of the range KMC 10spd chain (the gold one) on a wide range 9spd Tiagra cassette, with a XT 9spd small cage rear derraillier and Tiagra shifters. At the front I use a Narrow wide chainride specifically for 10spd chains and a pair of second hand ultegra compact cranks.

This has worked so well, it is so tough and has not put a foot wrong in 1000s of bumpy miles. The two drawbacks are the relatively large spaces between gears and the fact that you have to run an inline cable adjuster. Top tip for this set up is keep the cable tension high, the strong spring in the rear mech allows for this and keeps changes positive and crisp.


Sold something in our classifieds? Find this site valuable?

Consider a donation to the cause. We're cheaper than eBay fees, and it helps us here at CXM keep the lights on!

Enter any amount below, and click on the cow for some good karma. Thanks!




© 2024   Created by Cyclocross Magazine.   Powered by

Badges  |  Report an Issue  |  Terms of Service