Re: chain rubbing chainstay
Using a chain tensioner isn't a 'bandaid' on some bike frames, it's a necessity. Due to chain stay design some frames will not allow running without a way to guide the chain away from the chain stay.
Installed correctly a tensioner is far from the 'bad guy' that some make them out to be. The key word here is 'installed correctly'. If you've had bad luck with a kit supplied tensioner then it might be that you have not read the numerous threads devoted to the subject. Spreading the chain stays is one way to get the necessary clearance. Apparently you've tried that without success. Now you might want to explore a way to 'guide' the chain away from the frame and that would be the use of a tensioner.
There is a lot of good advice available here on ways that others have addresed this problem. Use the search feature, keyword, 'tensioner' to see what your options are.
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