14/10/2026
🔧 KE PERFORMANCE | KLX250 → 408cc
Another challenging project — and possibly our final KLX big-bore stroker kit.
Originally, the customer ordered a KLX 402cc kit. However, due to a miscommunication between our workshop and the machine shop manufacturing the crankshaft, the stroke ended up slightly different from what we originally planned.
The stock stroke is 61.2 mm, and our target was 63.2 mm (+2 mm total stroke). However, the finished crankshaft came with a 64.2 mm stroke, bringing the engine displacement to approximately 408cc instead of the originally planned 402cc.
Before shipping the kit, I will assemble the crankshaft, piston, and cylinder on a testing jig to verify that all components work together correctly.
This includes checking crankshaft rotation, piston movement, possible interference between components, and piston deck height to ensure everything is within the required specifications.
This KLX 408cc kit may also be the last one we produce.
Some components are becoming increasingly difficult to source, while others require custom manufacturing. The entire process can take at least 2–3 months, sometimes longer.
I understand how frustrating long waiting times can be for customers, and I don't want to keep accepting orders if I cannot provide a reasonable production timeline.
Although these projects are challenging, my priority has always been to carefully inspect and verify every component before shipping.
Building a larger-displacement engine is not simply about increasing the bore and stroke. Every measurement and clearance must work together correctly.
Thank you to all our customers for your continued trust and support. 🙏
KE PERFORMANCE | Built with Precision.
