The phrase "affect the speed at" is correct and usable in written English.
It can be used when discussing factors that influence the rate or pace of a process or action.
Example: "Several variables can affect the speed at which the project is completed."
Alternatives: "influence the rate at" or "impact the pace at".
The case could affect the speed at which Uber's self-driving efforts come to market.
"What's happening now may affect the speed at which we complete this final phase," he said in an interview.
Noise does not usually affect the speed at which work is performed; it may increase the number of errors, however.
The temperature and density of water affect the speed at which sound waves travel through it, and allowances have to be made for variations in these properties.
Partisan manoeuvre may affect the speed at which legislation is passed, but it often ensures that minority views are heard and taken into account.
The dynamics of this recycling will affect the speed at which the ATP-binding sites once again become available for PAQ binding.
Some researchers are also studying how a social network's structure affects the speed at which people adopt and stick to health habits.
The stress is due to more extreme temperature fluctuations than the southern slope sustains, which affects the speed at which the plant tissues, frozen during the cold night, are thawed.
Some of these people are nice, and some are nasty, and this naturally affects the speed at which the teeming wonders of India will open them up to real, life-affirming values.
Important printer characteristics include resolution (in dots per inch), speed (in sheets of paper printed per minute), colour (full-colour or black-and-white), and cache memory (which affects the speed at which a file can be printed).
However, the side-to-side movements of the plane's nose – its "yaw" – also affected the speed at which obstacles appeared to be approaching, confusing the plane's obstacle avoidance system.
