Ask a Mechanic | Mountain Triple to Double Conversion & Where to Spend Your Money On an SLX Mountain Group Upgrade

Welcome to our Ask a Mechanic column where our expert mechanic Daniel Slusser answers your bike maintenance questions. If you have a question for Daniel, please post it on our Facebook Wall or e-mail Daniel directly at Today’s column offers some tips on 3×9 to 2×10 mountain conversions and where to spend your money on a Shimano SLX group upgrade.

Sram XO 2x Crankset

Cranks like this Sram XO unit can be 2x cranks just as easily as 3x. Just remove the big ring and bingo! You have a 2x crankset (bashguard optional).

Question: I was reading an old post on your blog about converting from a 3×9 to a 2×10. You mentioned there was a way to convert a 3×9 front shifter to a 2×9 or 2×10. I currently have an XT 3×9 front shifter. How do I convert it to 2×10 capability? From: Roger

Answer: If you want to continue to use your 9spd front derailleur with two chainrings, just be sure that you continue to use 9spd rings. Reset the front derailleur outer limit to prevent it from shifting past the middle ring. Your standard 3×9 front shifter will work great with this setup. You just won’t have access to the click for the big ring anymore. Then, if you go to a 10-speed setup out back (requiring a cassette, rear derailleur, and rear shifter), be sure to get a 10-speed chain as well and you will be all set. The 10-speed chain will fork fine on your 9-speed chainrings.

Question: I read your blog post on where to spend your money on Shimano XTR upgrades and I am now in a similar situation. I would like to upgrade to SLX and plan on acquiring the following spec: full SLX groupset, but with an XT M786 rear derailleur. I plan on buying a Shimano MT65 wheelset as well. The other option is to go SLX entirely and save a bit of cash, but having the bling of XT is so tempting. From: Pierre

XT M770 Rear Shifter Pod

The rear shifter is where all the shifting magic happens and is more important to precise shifting in my opinion than the rear derailleur.

Answer: I think you have a great plan. SLX is a solid group with few faults to be found anywhere. The biggest benefits in going with the XT rear derailleur are the upgraded pulleys, tighter overall construction, and nearly 50g in weight savings. If you can afford it, I would upgrade the shifters to XT too, or at least the right shifter. You can really feel the difference in quality and precision between SLX and XT shifters. Plus the XT units will last longer and save you some money in the long run.


Daniel Slusser is a professional bicycle mechanic with over ten years of experience. He holds a bachelor’s degree in business administration from HSU and a master’s degree in history from Cal Poly. When he is not riding, wrenching, or writing he enjoys spending time with his wife and two children.