Author Topic: Gear ratio reduction  (Read 2557 times)

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Offline AlexItaly

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Re: Gear ratio reduction
Reply #10 on: October 27, 2020, 07:34:00 AM
This is an additional option, not just for weight reduction but for other practical reasons, like the life and the safety factor. I have already selected the brand, BC Lithium Batteries and model, BCTZ10S-FP. It costs here in Italy around 160 euro. Our current battery is 3.1 kg, while the lithium one is 0,8: so 2,3 kg saved, not bad.
Back to the chain, I have compared 4 brands. For each brand, I've selected the best chain available, 520 and 525. The brands are DID, AFAM, REGINA and EK. All of them work in racing championships, and the reliabililty is well known. I had a surprise: EK520ZV3 model has more tensile strenght then 525/137 ZRP REGINA chain, and it's very close to EK525ZVX3. The EK520 is rated for bikes up to 1200 cc, while all the 525 are rated for bikes up to 1300cc. The difference in choice is due to the torque, more then the power. Our bike has a very high torque, but it's a 4 cylinders in line, and very smooth. Finally, i decided to put on a 17 teeth front sprocket ( one less ), a  46 ( as the original ) rear sprocket in ergal, and the EK520ZV3 chain, 120 links ( same links of the original one ). I'll be very carefull in maintenance and checks of the chain conditions: before it breaks, in case, it will start to extend more then normal.