SAFETY HAZARD - RAD Mission - Chain Tensioner Failure


Thanks everyone for the heads up here. Thought about ordering one of these because of discount but will not now. Fact that Rad will not acknowledge this issue widely makes me hold off purchasing. Imagine a new car drive train failing soon after purchase. That model would be recalled immediately. Rad should use the auto industry approach to safety and at least issue a technical bulletin on the issue. This is a potential safety issue and I won't compromise safety of my family with one of these bikes.


New Member
Just want to chime in that I have also had trouble with the chain tensioner. The original failed and was replaced. A month later and 173 miles later, and the replacement has failed in the same way as the original. Working with Rad on a 2nd replacement, but I'll also see if the local bike shop has any ideas for a quality replacement.

If you have this problem you'll know because the chain tensioner hitting the spokes is loud (and not good for the spokes long term)

The failure I experienced is a bolt breaking off / failling out same as the original poster.


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  • 03 bolt missing.jpg
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  • 06 fix touching with hand.jpg
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New Member
Got my Radmission yesterday and my chain tensioner broke on my first ride. Not sure if it got caught in the spoke or what but I'm so disappointed right now. I was pedaling and I heard some grinding noise and then saw the chain tensioner just hanging there on the chain. The bolt that secures the chain tensioner to the frame broke in half and now it is stuck in the frameView attachment 89952 View attachment 89953

Edit: Contacted support through email and they are sending me a replacement chain tensioner. I was surprised how fast they responded as all the things you read online suggest it takes them some time to respond. Will keep you all updated once the new part is installed.

Update: I ended up finding a local mechanic that was able to repair and improve the old chain tensioner with a sturdier steel bolt instead of the weak aluminum bolt. Rides good now. The replacement chain tensioner is on the way but I don't need it anymore.
Exact same thing happened to mine, broken right out of the box. Haven’t even ridden it!
Got any picks of what the bike mechanic did to fix it?

Rad and Sad

New Member
Exact same thing happened to mine, broken right out of the box. Haven’t even ridden it!
Got any picks of what the bike mechanic did to fix it?
Sorry to hear that! I think they get damaged and bent in shipping, Rad needs to do a better job of protecting the chain tensioner.

After riding with the fix from the mechanic I would say it's not ideal since it shifts up during hard bumpy terrain so I have to push it down when that happens. Possibly because there is no spring. I don't know. Anyways, here are the pics
fix 1.jpg
fix 2.jpg

john peck

Well-Known Member
That all of course makes complete sense. Right now I fully believe that RAD is drowning in their success and can't keep up with customer service. We all know what the long term result of that will be.

Same happened to Juiced, too big, too fast. It alienates folks. Bin looking for mission feed back. This
sounds like a serious issue, but perhaps a simple fix. It looks a rather awkward configuration.