So I’ve made this DIY single speed rear cog , which the chain is sitting on, and I had this tensioner from a Rohloff build.
When I pedal the bike in a stand the chain immediately drops down to the gap ( where I’ve got old cassette bits acting as spacers)
However it looks to me that the chain tension is decent (see second photo, showing crank , which is setup 3x). The chain drops down from the rear cog when the front is in the middle chainring
I know it’s a funky setup but I can’t of thought it would work as I’ve done similar before
I guess I should start by shortening the chain a few links?
Thanks 🙂
by -LetsTryAgain-
5 Comments
Make sure the chainline is pretty straight when you’re in the middle chainring up front. It could be falling off because the tensioner isn’t aligned properly and is trying to “shift” the chain off the rear cog
What does your chain line look like? Can’t tell from these photos.
Although this might work, the tensioner’s cage is almost certainly not long enough to handle three rings. If the middle ring and rear cog are lined up straight, I can’t think of why it would drop down except maybe you need a more flexible chain, like modern 1x chains need to be. It’s an interesting project you have there.
How exactly are you using this?
If you are trying to use the chainset as a triple it will not work a tensioner only tensions the chain in a single speed setup it may look like a simplified derailleur but it will not work on anything more than single speed.
Chain tension seems low. Rohloff recommends a straight vertical line up to 30 degrees forward of a vertical line. See here [chain tensioner ](https://www.rohloff.de/fileadmin/user_upload/8250_Kettenspanner_Montage_Faltblatt_A4_de_en_fr.pdf)