I have a Wahoo Kickr Core that I use with a 7 speed cassette. For personnal reasons I would like to convert it to fixed gear. I have seen some conversion kits (about 300$ US) on Velobike website. It is quite expensive so I would like to try cheaper option. Would it be possible to remove the rear derailleur and keep the 7 speed cassette, and only use 1 gear all the time?
The problem with my actual setup is that I want to keep using only 1 gear, but the chain sometimes skip to higher/lower gears for example when I pedal harder or go in standing position. No matter the adjustments I do on the rear derailleur it keeps happening.
So would it be possible to simply remove the rear derailleur and keep the 7 speed cassette but only use 1 gear?
The sprockets on multispeed cassettes have some teeth that are lower in height to assist with smooth shifting. Without a derailleur guide pulley the chain will tend to jump off onto a smaller sprocket.
Fixed gear technically means a hub without a freewheel, so that the pedals continue to turn with the wheel. The setup your are referring to is correctly called singlespeed.
If you want to run only one gear without a derailleur you’ll need to buy a single speed sprocket that has full height teeth to keep the chain on. They only cost about $10. This can be fitted to your existing freehub with spacers to get the correct chain line, spacers can be scavenged from your old 7 speed cassette or with new ones that only cost a few$.
@RichieS That will work for Zwift but for SYSTM the OP will need to remain in ERG mode or change levels manually. I think the OP’s issue is problems accidentally hitting the shifter so not sure it would completely solve the issue but I guess with the Cog the chain doesn’t go anywhere and the OP will just hear more chain noise when not in 14T.
Edit: just thinking further about this. Maybe the Cog/Click does make sense. In CX when we do a single gear race we just zip tie our shifters so that might work for @Datfatboy.