If you have a "wheel-on" smart trainer such as a Tacx Bushido or a KICKR Snap, you may find that your rear wheel "slips" or spins against the roller when you put the power down on the steep gradients.
There are a couple of steps you can take to stop or at least reduce this:
- Pump your rear tyre to at least 100psi
- Use a dedicated trainer tyre
- Make sure you are using the correct roller tension for your trainer
- Perform a trainer calibration or spindown
Reduce your Slope Limit setting: This is the maximum gradient percentage command that FulGaz will send to your trainer. You can access this in FulGaz settings -> Advanced Trainer Settings.
Many wheel-on trainers will "max out" at a certain percentage. You can check this by looking up your trainer's specifications on the manufacturer's website.
Reducing your Slope Limit to below the trainer's max level (or below where you're getting slip) will usually solve this issue.