Crankarms and shifters


Q: I have been riding my current bike for about a year, and I ride close to 40 miles a week on average. My Shimano Deore XT derailleur has been great, but I have noticed my trigger is getting harder to engage. What is my best route for getting it back to its original smooth operation. Is it something I can do myself?

A: After riding out in the dust and dirt, long cables and triggers can start to build grime or just lose their original lubrication. A new cable can often get you back to proper working order or at least get it much smoother. This can be done at home without too much technical ability other than having to get your cable reconnected to the derailleur and then adjusting the derailleur properly.

To take it a step further, you could replace your cable housing, which could be tricky on some bikes, particularly bikes with internal cable routing. You’ll have to look over your bike and decide whether or not it’s within your abilities. Replacing both the cable and housing will likely get you that new feeling back. If you want to make sure you’ve got all stones turned, you can take the trigger housing apart and clean or lube the inside with some brake cleaner. Liquid Wrench is also a good quick fix that cleans and lubricates.


Q: I’m thinking of buying an e-bike, and I want to know more about bottom bracket heights and why they matter to me as a rider. I want to get an e-bike that I can avoid pedal strikes with. What are the factors I should consider?

A: Bottom bracket (BB) height is something to consider, but there isn’t one definitive answer to what height is the best. It’s more a matter of how that bike is designed to handle, whether it’s more of a downhill style or something along the lines of a cross-country geometry. BB isn’t the only factor involved; in fact, many companies are running a relatively low BB but are compensating with shorter crank lengths. It’s common for people to be hesitant about shorter cranks often because they think they might lose some efficiency or acceleration.

Both this derailleur and the cassette (pictured below) are part of Shimano’s new e-bike-specific LinkGlide groupset and an attempt to make shifting even smoother for longer.

Studies, such as Jim Martin’s of the University of Utah, on crank lengths have shown minimal difference in power. Even between 120–220mm cranks the max power difference was only 4 percent. Other studies show that shorter cranks accelerate up to max power quicker. In other words, when you have the right combination of crank length and BB height, you can still achieve great performance while minimizing pedal strikes. Of course, technique on the trails will be the biggest factor, but completely avoiding pedal strikes may be impossible if you ride technical trails at all.


If you have any tech-related questions about the e-bike you currently own or are thinking of buying one, feel free to send your query to [email protected]