Woltjer Racing Engines sells new and rebuilt new engines. Only engines featured on our website are available for purchase. Please keep in mind that our stock is always changing and depending on the time of season, we may or may not have your new or rebuilt engine of choice in stock.

Engines only and complete packages are available.

Included in a complete engine package are accessories including clutches, exhaust systems, carburetors, engine mounts, spark plugs and more.

Services include:

  • Engine clean and complete inspection
  • Engine rebuild
  • Carburetor blueprinting
  • Break-in and dyno testing

Frequently Asked Questions

Listed below are some frequently asked questions with their corresponding answers.

Q: Do you build all of your motors the same or do you have different levels and pricing options?
A: We build all engines with the same attention to detail we would use if we were racing ourselves or building the engine for our own kid. Every engine is built one at a time from start to finish with our full attention by either Daniel Woltjer or Gary Woltjer to ensure quality control.  All Yamaha crank case bearing bores are re-sleeved and realigned. This is the only way to get a crankcase near perfect (±.00005″). Whether you are a club or national racer, your engine will receive the same treatment as the next customer’s.

Q: How do I get a national-level engine?
A: Order one!  We have no teams and no sponsored drivers. Selling great engines and winning races is a great incentive for us. The more success our customers earn only benefits our business and brand.

Q: Do you sell karts or just blueprint and rebuild engines?
A: We do not sell karts.  Our shop is 3,500 square feet full of the best lathes, mills, hones and precision tools just for blueprinting engines. We do all machining, blueprinting and dyno work ourselves. (Daniel Woltjer or Gary Woltjer)

Q: What maintenance is expected of me the racer to keep my Woltjer Engine running strong in between rebuilds?
A:  For Yamaha KT100s, Mini Swifts, Mini Roks and X30s we recommend replacing carb kits every race as well as cleaning carbon off the top of the piston as necessary for tech purposes.  Spark plugs should be changed every day.  Regular maintenance should include checking air/ fuel filters.

For the X30, the gear oil should be changed every weekend of racing.

Q: How often should I have my engine rebuilt?
A: Depending on use and abuse the time varies quite a bit. Usually our customers get anywhere from 5-10 hours in between rebuilds to maintain peak performance.  This time varies immensely depending on the amount of dirt that goes through the engine even though you are using an air filter. We also recommend oiling your air filter with 2-cycle oil and squeeze it like a sponge.  This will not reduce your airflow or performance whatsoever.

Q: What oil / fuel ratio do you recommend in your engines?
A: 8 oz. per 1 gallon fuel for X30s and Yamahas.  6 oz. per 1 gallon fuel for Mini Roks and Mini Swifts.  We recommend Red Line Oil if permitted by your series or track rules.

Q: Do your engines require a break-in period when I receive it?
A: All engines are dyno-tuned at our shop and then tested for performance prior to returning to the customer. The engine will not need a break-in session after you receive it. If you do not wish to have your engine “broke in”, please let us know.  For water-cooled engines, you may need to warm them up prior to your first race.