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 firstname.lastname@example.org.
Question: I am ready to make the upgrade to 10-speed mountain components. I really want to go with XTR but I don’t have the money. Is it possible to only use some XTR components without losing too much performance? If so, where do you suggest substituting other parts? From: Ricky
Answer: XTR on the cheap: I like it! There is no doubting the performance of Shimano’s top of the line mountain group. The Dyna-Sys 10-speed XTR M980 group is tremendous in every respect including price, but there are some places you can save money without giving up too much in the way of shifting quality.
When it comes to shifting performance, rear derailleurs are highly overrated and front derailleurs are highly underrated. The rear derailleur can only be as precise as the shifter attached to the other end of the cable. Because the indexes are so small in a rear shifter a little bit of imprecision in the mechanism makes a big difference at the derailleur. Mating an XT rear derailleur or even an SLX model to an XTR rear shifter will work far better than doing the reverse as bikes are often specced from the factory. The reason product managers spec high-end rear derailleurs and cheap shifters on new bikes is because the rear derailleur is much more visible than the shifter and therefore more enticing to customers making a purchase.
With respect to front shifting, I have never used a front shifter that didn’t work great. Sure some low-end offerings don’t feel that smooth or precise but they all work reliably and never miss a shift. Your money is better spent on an XTR front derailleur. XTR derailleurs come with stiffer springs and a thicker steel cage that does not flex as much as its XT and SLX counterparts when pressed against the chain during a shift.
As for the cassette, my recommendation would be to go for an XT block because it shifts almost identically to an XTR cassette but lasts longer because each of the cogs are made of steel rather than titanium. For cranks you can’t beat XTR, but it is the most expensive component in the group. In my experience the XT and SLX chainrings shift great. The performance of XT and SLX rings is almost exactly the same and the weight difference between the two is negligible, so my budget pick for a crank is SLX.
When it comes to bottom brackets, the XTR unit features lower friction seals and higher quality bearings than XT and SLX. The price difference between the all three isn’t much, so my bottom bracket pick is the XTR BB93 for threaded bottom brackets and XTR BB94 for press fit bottom brackets.
For the chain I would just go whole hog and get XTR. The finish is better, which results in smoother shifts. Plus XTR chains have more stainless steel parts to resist rust better than the budget chains.
When it comes time to stop, there is no difference in braking power available from XTR Trail, XT, and SLX disc brakes. So the primary difference is weight and features. XT has all the same adjustment features that XTR has, including tool free reach adjust and free stroke adjustment. The SLX brake is the same brake as XT, but doesn’t have the free stroke adjustment screw. Personally I don’t think the free stroke adjustment screw is necessary, so my budget pick for brakes is SLX. However, the price difference between the two is small, you might as well get XT if you can spare an extra 20 bucks.
For brake rotors, you want to get rotors equipped with Shimano’s Ice Tech. This type of rotor uses a thin sheet of aluminum sandwiched in the center to help dissipate heat faster than full stainless steel rotors. While the XTR RT99 rotors are certainly the best in the lineup, they are pricy and only compatible with centerlock hubs. So, I recommend that you go with SLX RT68 Ice Tech rotors if you have centerlock compatible hubs; and for folks with 6-bolt hubs, you’ll need to go with the slightly more expensive XT RT86 Ice Tech rotor.
To sum it all up the best bang-for-the-buck 10-speed XTR build would be an XTR rear shifter, SLX or Deore front shifter, XTR front derailleur, SLX rear derailleur, XT cassette, SLX crank, and XTR chain. While this combination will not produce the most cohesive looking build, I think you will love the performance. Moreover your significant other will love that the thickness of your wallet hasn’t been reduced to that of a business card by your purchase.
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 State University. When he is not riding, wrenching, or writing he enjoys spending time with his wife and two children.