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. Today’s column answers questions on cross compatibility between SRAM and Shimano road cranks and features tips for eliminating upper back pain on road rides.
I’m using old SRAM Red cranks with 7800 Dura Ace rings and derailleurs. I already have a Force GXP BB in my parts bin. Can I upgrade to the Red 2012 Exogram cranks whilst keeping everything else Dura Ace? From: acmoc via youtube
None of us have tried it yet or know anyone who has. However, we took a few measurements and found that the distance between the rings on Exogram cranks and Dura-Ace 7900 and 7800 is practically identical. FSA measures the same too, which makes sense because FSA cranks are common OEM spec on bikes with both SRAM and Shimano shifters and derailleurs. So, it would probably work, but the shifting won’t be ideal. Of course you would have to use the Red chainrings that come stock on the crank because of the different orientation of the 2012 Red bolt circle with its “hidden bolt” that attaches to the crank arm directly.
Just remember that SRAM spent a lot of time making sure that the Red 2012 yaw front derailleur would work perfectly with the Exogram chainrings. If you decide to forge ahead with the Exogram crank on your Dura Ace 7800 group, just keep in mind that SRAM voids warranties on their products when they are used with competitor’s offerings.
My upper back is giving me problems on longer rides. 30 miles in and my back is sore. I have an old 1990’s era Nishiki with the stock handlebars and brake levers. Will raising up my handlebars help get rid of the pain? From: Ed
Upper back pain can come from a number of different sources. Zeroing in on where you are feeling the pain can help to identify the cause on the bike. Pain between the shoulder blades is usually caused by handlebars that are too wide. If the pain is in your neck or where your neck transitions to your back, then your handlebars might be too low and/or your stem is too long. Having your saddle nose pointed downward can create upper back pain as well by placing too much weight on your hands. Keep each of these points in mind as you search for relief.
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.