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It’s easy to own a 144cc or 300 cc Two-Stroke!
One of our passionate readers started circulating a petition to the AMA to allow two-stroke race machines into the Pro ranks. His suggestion was to allow a 144cc two-stroke to compete in the 250F class and a 300cc two-stroke to compete in the 450F class. While it’s not the ideal many two-stroke fans would choose, it is a step in the right direction. It’s
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Can a Two Stroke run at 200:1 fuel/oil Mixture?
When someone says they can run their two stroke at 200:1 the first thing that happens is that people’s eyes go wide and they say “Huh?” It happens every time the Project Two 50 team mentions they are running a 200:1 mixture. Of course there are many that are skeptical. How can anyone
MICROBLUE Racing sponsors Project Two 50 -Results in Low Emission YZ250 Two-Stroke
One the biggest supporters and sponsors of Project Two 50 is our friend Craig LeClaire from Micro Blue Racing located in Rockford IL. His ideas, suggestions and input have taken our simple idea and turned it upside down. The original idea
Reader Rebuild – 2005 KTM 200 EXC
Here is the story of my rebuild of my 2005 KTM 200 EXC, twostrokemotocross.com inspired me to have a go and do it myself. Since starting racing as a 10 year old in 1984, I have had two dirt bike ambitions I really wanted to fulfil, first to ride a 500, second to rebuild my own motor. Well the first was
Engine Build HPP Valve Honda CR250 – Part 9
This is part nine and the final part of the CR250 engine build and will cover head, reed valve and carburetor installation. I will also perform the initial leak down test. Tools needed: Torque wrench, leak down tester, metric tool assortment Apply oil to the six cylinder head studs and install them into
Engine Build HPP Valve Honda CR250 – Part 8
This segment will cover piston, rings and cylinder installation and power valve adjustment. Tools required: Torque adapter, torque wrench, standard assortment of metric tools. Most people have rebuilt the top end of their ride so a lot of this information is old news. I am presenting the techniques
Engine Build HPP Valve Honda CR250 – Part 7
Part seven of the CR250 engine build. Now that the bottom end is done, we can turn our attention to the top end. Top end segments include, cylinder and cylinder head prep, power valve installation and set-up, piston and rings, reed valve and carburetor. This segment will cover power (or exhaust) valve
Engine Build HPP Valve Honda CR250 – Part 6
Part six of CR250 engine build. This is a short segment on the installation of the ignition components, countershaft sprocket, kickstart lever and ignition cover. To install the stator plate, match the mark at the bottom of the plate to the casting mark on the case Apply
Engine Build HPP Valve Honda CR250 – Part 5
Part five of the CR250 engine build. This segment will cover the installation of the clutch pack, right side cover, power valve governor and water pump cover. Before installing the power valve governor, coat the throwout balls and the rack with a 50/50 mixture of moly 60 grease and transmission oil.
Engine Build HPP Valve Honda CR250 – Part 4
This is part four of the CR250 engine build and will cover the assembly and installation of the kickstarter, idle wheel and gear change mechanism. To assemble the shift pawls and springs, coat the springs, plungers and pawls with transmission oil. Insert the pieces into the shifter and place the completed


