I’m investigating the idea of doing a KA race next year, but am not certain what is required to compete at top-level regional/national races. Are people using multiple engines (one practice, one race) or is it possible to use one engine for Fri/Sat/Sun without a drop in performance?
I would hope that if I’m able to do an entire 3-day weekend with one KZ engine that the same would be the case for KA…what has your experience been?
You don’t need 2 KA’s if you are looking to run a single event or even just a few. For the most part you can run them to 6-7 hours without any significant drop in performance. I won USPKS warm-up at MCC on a motor that had 7.5 hours on it.
For a 3 day race weekend I show up on my race motor and it only comes off if there’s a problem.
If you’re running more than 1-2 races there is a TON of flexibility that comes from having a second motor to help strategically keep hours off of what you might determine to be your “primary” and also helps with extended turn-around times from builders to get them freshened but we ran our first 2 years on KA’s with only a single motor each for the full season and still did OK.
If the motor is fresh at the start of the weekend, you’d be fine to run the whole weekend on it. I personally preferred having a practice motor to load time on and just run the race motor for the last practice, happy hour, and the actual race, but I was also stretching a race motor over 2 or 3 weekends at a time. You can definitely do a full weekend on one motor.
Agreed with all of Andy’s comments. One of my goals for '24 is to better track the time on my motors, but the engine with which I won Stars at Pitt definitely had north of 8 hours on it since it was last freshened. Some people may disagree, but I think money is better spent elsewhere than having a fresh top-end for every Stars race weekend.
Typically, I run the first 3-4 practice sessions on Friday with my “practice” motor, and throw the “race” motor on at the end of the day to make sure everything is working properly. This is more of a peace of mind exercise as I feel like I’m saving motor time with (3-4) 7 minute session. In reality, I could probably just run the “race” motor all weekend.
If you’re doing 1-2 events, one motor is definitely sufficient and I’d even argue 3-4 weekends it would work. Above that, if you include test days, it’s probably best to have it freshened or have a “practice/beater” motor. Obviously with the caveat that I’m monitoring it along the way and rebuilding the carb, putting fresh plugs in, etc.
You don’t need a fresh engine or two engines. I was going to run the Route race on an engine that had a full season of testing on it before I blew it up.
As noted the 2nd motor is just there to keep time off the primary race motor and be available for backup replacement parts if needed. It’s definitely not needed for a single race weekend.