Interesting TCU Problem


Payson, Arizona
I will try to keep it short. My wife and I have identical new Creo's, Expert EVO. I purchased a Bryton 750 bicycle computer. (nice computer for the $$). I purchased the bundle with Speed, Cadence and HR. For some reason when I ride and am using the speed sensor for my speed source it is multiplied by 10X on the display. Hence 12 MPH is displayed as 120MPH. Sort of like the decimal is in the wrong place. The same computer on my wife's bike is just fine. I trouble shot it down to the TCU. (nice to have two bikes). When the bike is powered on this problem manifests itself but when powered down it does not. Keeping it short, I swapped TCU's between bikes and the problem followed my TCU over to my wife's bike. Her TCU on my bike, all was fine. I checked Mission Control and all hardware and software revs were identical between bikes. My shop is putting in a warranty claim for my TCU. The only difference I see of the marking on the TCU's is a small stamped number on the very bottom. My wife's TCU is stamped with *2025 and mine is *2028. Have no idea what that means. I might shoot off an e-mail to Specialized. I am sort of worried if I get another 2028 the problem will still be there. That said it may mean nothing and I just have a bad TCU. I can work around the speed issue by using the GPS data instead of the speed sensor. Just thought I would post this in case anyone experiences anything like this. Doubtful but maybe. You can see in the computer side by side picture that my computer is 10X my wife's computer. Good bug. Never could have found it without having two bikes. I would have driven the computer guys crazy fixing something that was not their bug.


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