Hey, I am new here!!!!

swampy20

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Wish I could show ya'll my new bike but I hit a snag at day one of owning it. It is a Trek Rail 9.7 gen 2. Took it out on its first mayden voyage and the chain broke. It's been at the dealer for over a week. I kind of got turned off by the bike despite the fact that it ripped when I rode it. Please convince me that I should keep it or is it a bad omen and should I rather return it and find a different bike. It turns out it is a known issue with the bike which can be fixed but I am not sure I can trust it now.
 
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You’re the victim of bad luck. A chain is so minor and is likely a small issue that was caused through something simple or a manufacturing defect.

Keep it. Ride it. Enjoy it. Become an eBike zealot.

Welcome!
 
Thanks. I guess I am just frustrated that my brand new bike broke a chain after day one.
 
Thanks. I guess I am just frustrated that my brand new bike broke a chain after day one.
Its a bugger but all i can say is ive owned my rail for over 3yrs now and its still a blast on trails and bike parks
And im running it over stroked with Dual crown forks so its having a hammering :) But well looked after
So i would get it back and enjoy it (y)
 
It’s very tempting to start of a new ride in Turbo and 12th gear. (I’m not saying you did that). The torque available from these motors is impressive …but there’s a limit.

Cadence of +/- 80 is usually the sweet spot …especially with e-motors. Excessive wear and tear on components is possible if you fall below that crank rpm or cadence.

Motors, chains, quick links, cassettes, free-wheel, chainrings and sometimes even peddle bearings, will last longer.
 
Its a bugger but all i can say is ive owned my rail for over 3yrs now and its still a blast on trails and bike parks
And im running it over stroked with Dual crown forks so its having a hammering :) But well looked after
So i would get it back and enjoy it (y)
Thank you, that sounds encouraging!!!! Just what I needed to hear.
 
Try backing off the pedal pressure slightly when changing gear. It takes a huge amount of force to snap a chain. My best guess is that it happened when you were changing gear, when the chain is at an angle and the chain can be peeled apart more easily than just snapping it.

Another time when chains go bang is when you get a big obstruction in the mech. In such circumstances not only do you get a mech broken in two, or at least badly bent mech arms, but also a broken chain. (OK, yes, I'm talking from personal experience here, four times, I'm now on my fifth mech!)

None of these are problems with the bike brand, they are component problems, problems with the trail you are riding, and last but by no means least, rider error! :)
 
I've been riding mtb's for close on 30 years and emtbs for the last four of those years ..I had a similar outcome in terms of snapping a chain within a couple of weeks ..
Stihldog & Steve Sordy have provided good advice ..I will only add to that by saying ride in a slightly lower gear than you actually need which will ease the strain ..and you won't have too many problems in the future ..
Snapping a chain though really is very minor ..when you collect your bike from the dealer buy a chain link and ask them to show you how to fix it
Good luck ..
 
Try backing off the pedal pressure slightly when changing gear. It takes a huge amount of force to snap a chain. My best guess is that it happened when you were changing gear, when the chain is at an angle and the chain can be peeled apart more easily than just snapping it.

Another time when chains go bang is when you get a big obstruction in the mech. In such circumstances not only do you get a mech broken in two, or at least badly bent mech arms, but also a broken chain. (OK, yes, I'm talking from personal experience here, four times, I'm now on my fifth mech!)

None of these are problems with the bike brand, they are component problems, problems with the trail you are riding, and last but by no means least, rider error! :)
Thanks for the thorough explanation. I am by no means blaming the brand. I love Trek. I own 3 other Trek bikes. Friends tried talking me into other bikes and I am a die heart Trek fan. Their geometry works perfect for my body setup.
The chain broke riding on a flat terrain. The dealer like myself did some research and it's a known issue with this specific model. They are hopefully fixing it and it will be all put behind me. I am definitely going keep your wisdom and experience on this in mind out there on the trails. Ride on!!!!
 
It’s very tempting to start of a new ride in Turbo and 12th gear. (I’m not saying you did that). The torque available from these motors is impressive …but there’s a limit.

Cadence of +/- 80 is usually the sweet spot …especially with e-motors. Excessive wear and tear on components is possible if you fall below that crank rpm or cadence.

Motors, chains, quick links, cassettes, free-wheel, chainrings and sometimes even peddle bearings, will last longer.
Thanks for the explanation.
 
Breaking a chain on your first e-bike ride is 100% operator error. Its not the bikes fault. You simply mashed the pedals and changed gears underpower and ping goes the chain. You'll need to re-adjust your technique to allow for motor power and back off slightly while changing gears.

As an example I had my E bike for 1 year, never broke a chain and lent it to my mate (non e biker) to try and within 1 minute of riding had snapped the chain. I fixed up the chain and haven't broken a chain since 10 months later.

It's all about finesse when changing gears and understand when you can and cant shift underload.
 
Breaking a chain on your first e-bike ride is 100% operator error. Its not the bikes fault. You simply mashed the pedals and changed gears underpower and ping goes the chain. You'll need to re-adjust your technique to allow for motor power and back off slightly while changing gears.

As an example I had my E bike for 1 year, never broke a chain and lent it to my mate (non e biker) to try and within 1 minute of riding had snapped the chain. I fixed up the chain and haven't broken a chain since 10 months later.

It's all about finesse when changing gears and understand when you can and cant shift underload.
Thanks. I appreciate all the input. It sure makes me feel a ton better after dropping over 5k. Lol. From all that I have read, I am at least convinced that just like with computers the majority of the issues are user induced. I am not entirely new to ebiking but definitely can use some good advice like this to help improve how I ride. I will hopefully be able to put this behind me and enjoy my rides. The dealer as did I did do some research and found that this model has a known issue with chain breaks. Hopefully the new chain will fix that. From your input and those of others I am gathering that there is a fine dance between the torque strength, cadence and gear ratio, which I will be paying attention to. Really appreciate the time to explain this.
 
Thanks. I appreciate all the input. It sure makes me feel a ton better after dropping over 5k. Lol. From all that I have read, I am at least convinced that just like with computers the majority of the issues are user induced. I am not entirely new to ebiking but definitely can use some good advice like this to help improve how I ride. I will hopefully be able to put this behind me and enjoy my rides. The dealer as did I did do some research and found that this model has a known issue with chain breaks. Hopefully the new chain will fix that. From your input and those of others I am gathering that there is a fine dance between the torque strength, cadence and gear ratio, which I will be paying attention to. Really appreciate the time to explain this.
I have 4 mates with Trek Rails. They are great bikes. Those bosch motor system is indusrty leading. Shimano and sram drive trains are tried and tested. There's nothing other than weird chainline that the manufacturer of the frame can do to make the chains break more than others. My mates with their rails don't break chains.

In my view chain breaking regardless of E or mtb is technique, set up, wear and or foreign object related. As the bike is new its not wear related. That leaves set up, technique and foreign object. Your'd know if it was foreign object as there'd be a stick stuck in the gears. So that leaves technique and or set up.

I say get the bike back and ride it like you stole it. This time with a little back off when shifting.

Side note. Be weary of boost mode run on. Motor run on can screw stuff up once you have stopped pedaling. I've witness two derailluers get chewed up and spat out after the rider stopped pedaling because of motor run on.
 
Wish I could show ya'll my new bike but I hit a snag at day one of owning it. It is a Trek Rail 9.7 gen 2. Took it out on its first mayden voyage and the chain broke. It's been at the dealer for over a week. I kind of got turned off by the bike despite the fact that it ripped when I rode it. Please convince me that I should keep it or is it a bad omen and should I rather return it and find a different bike. It turns out it is a known issue with the bike which can be fixed but I am not sure I can trust it now.
all bike's can and do have problems, as long as the replace the chain under warranty I wouldnt worry about it. and if you sell it youll lose out on some of your dollars and you'll have to buy another one. and when you get it back dont change gears while your pedaling hard in Turbo, just saying
 
all bike's can and do have problems, as long as the replace the chain under warranty I wouldnt worry about it. and if you sell it youll lose out on some of your dollars and you'll have to buy another one. and when you get it back dont change gears while your pedaling hard in Turbo, just saying
Thanks.
 
Whole week to change a chain???
My explanation wasn't thorough enough. It wasn't just the chain, it turns out there was a manufacturing default on the chainring itself, which caused the chain to skip. It was very slight and unnoticeable when riding but the mechanic changed the chain and it kept bouncing off in the smallest cassette. He then did more investigating and found the issue. They had to order a new chainring and that is what took the time. Got the bike back and we have been out riding 3 times and it is running like a dream.
 
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My explanation wasn't through enough. It wasn't just the chain, it turns out there was a manufacturing default on the chainring itself, which caused the chain to skip. It was very slight and unnoticeable when riding but the mechanic changed the chain and it kept bouncing off in the highest gear. He then did more investigating and found the issue. They had to order a new chainring and that is what took the time. Got the bike back and we have been out riding 3 times and it is running like a dream.


Just curious, do you know what was wrong with the chainring? …or chain?
 
Just curious, do you know what was wrong with the chainring? …or chain?
The chain broke very shortly after I took it on it's first ride. The technician replaced the chain but it kept falling off when in the smallest chainring, which happened to me twice while riding and then it broke the 3rd time. Upon further investigation by the technician he found that the chainring had a defect that made the chain skip. It was replaced and now the chain is fine.
 
My thoughts exactly.
Not exactly a difficult thing to sort, and nice to have the tools and experience should that happen in the middle of nowhere
It was absolutely my negligence to not have my toolkit with me to do exactly that, but it turns out even if I would have fixed it, it wouldn't have held up. The issue was with the chainring that had a defect and that is why it took so long. The part had to be ordered. Happy to report it is now fixed and I am clocking lots of miles without issue.
 
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