Nige here in sunny South Yorkshire, England.

[Treborbane]

Had my Giant full e+1 for 3 yrs now. I'm 70 and it keeps me fit. Love off-road trail riding. I change the chain at 300 mls and the sprockets at 600. Just put a new SRAM 11 spd on but there is now a horrible grinding noise from the motor. Any ideas ???

 

[Bigal1463]

Welcome Treborbane to EBR, the most friendly and informative site going. I’m no bike mechanic or even close, but why do you replace the chain and sprocket so frequently? I never heard of anyone doing that.

 

[Treborbane]

Welcome Treborbane to EBR, the most friendly and informative site going. I’m no bike mechanic or even close, but why do you replace the chain and sprocket so frequently? I never heard of anyone doing that.

Hi. I'm a big guy. 17 stone. I like to go for it a bit off road and I don't have the time to clean the chain after every ride. Chains cost very little (about £11) and I'd rather replace them regularly than have one snap whilst out on the trail. Here in Yorkshire it's very hilly and VERY muddy and the combination of my weight, the bike's weight and the power of the motor stretches the chain relatively quickly. All that aside I need to know why the horrible grinding type noise is happening.

 

[Treborbane]

Magic. Found out the problem. My Sram chain has wide n narrow spaces. My front cog has wide and narrow teeth. I had, without knowing, put the wide chain gaps onto the narrow teeth. Terrible grinding, sorted.
Anyway, hi there you USA guys n gals. Here in Yorkshire it's 33degC and VERY VERY HUMID. If it keeps it up I'll be putting dry lube on my new shiny chain.