For this build, we started with a fairly beat-up 2005 KTM 300 EXC. We wanted to see how close we could get it to a new KTM 300 (minus the electronic start of course). We came pretty close, and Dirt Bike Magazine liked it so much that it ended up on the cover of the magazine.
We did a full frame-up restoration on this bike, going over every part and bolt. We took our time with other projects in between, and it took nearly three months to complete.
We rebuilt the engine and checked every pivot point on the bike. We put in a new drive, bled the brakes, freshened up the suspension, and touched everything else up to make sure it was in perfect condition.
One big complaint on 300s is the vibration you can feel, and that was reduced with Crank Works working their magic on the crankshaft. Crank Works actually does a bunch of complicated math to calculate out the best place to add and or take away material on the crank webs to make the bike vibrate less. Nearly all top factory teams run a balanced crankshaft for optimal performance and less vibration. The crankshaft is also balanced to work perfectly with the piston you are using.
One thing I have been impressed with on these older KTMs is their durability. In many cases, their parts don’t wear out as quickly as other bikes and still work well even after a lot of use. Many of the parts we replaced were switched out only because they just looked too beat up, like the plastic and pipe.
There are so many important parts of a build like this, but our key areas of focus were on the motor and suspension. You can have a great time on a bike that has these two areas in good shape. Many of the other parts we added to this build improved comfort, functionality, and (of course) looks.
After all of this work, we ended up with a bike that is close to as good as a new KTM that will last us another 10 years on the trail.
Products Used for this Build
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| Hot Rods Complete Crankshaft | Hot Rods Crankshaft Bearing and Seal Kit | Vertex Piston Kit |
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| V-Force Reed Cage | FMF Gnarly Pipe | FMF Turbine Core 2 Silencer |
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| Pivot Works Steering Stem Bearing Kit | Pivot Works Shock Rebuild Kit | Pivot Works Swing Arm Rebuild Kit |
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| E Line Carbon Pipe Guard | Cycra Shrouds, Side Panels and Mud Flap | Cycra Ultra Pro Bend Racer Pack |
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| Uni Two-Stage Air Filter | CV4 Coolant Hoses | CV4 High Pressure Radiator Cap |
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| Renthal Rear Twinring Sprocket | Renthal Fatbar | Renthal Kevlar Grips |
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| Dunlop AT81 90/90×21 | Dunlop MX3S 110/100×18 | Motoseat Seat Cover |
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| Works Connection Front Brake Cap | Works Connection Clutch Reservoir Cap | Hinson Fibers, Steels, Springs and Outer Cover |
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| Tusk Oversized Rotor | Tusk Rear Disc | Tusk Rim |
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| Tusk Spokes | Tusk Brake Bolts Kit | Tusk Shifter |
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| Tusk Rear Brake Pedal | TM Designworks Rear Chain Guide and Slider | Trail Tech X2 Headlight |
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| Trail Tech Kickstand | Primary Drive O-Ring Chain | Primary Drive Sprocket Bolts Kit |
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| IMS Fuel Tank | IMS Pro-Series Pegs | Klotz R-50 2-Stroke Pre-Mix |
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| Attack Graphics Custom Graphic Set | OEM KTM Frame Guards |
Do you have an old, beaten bike that could be freshened up to look like new? What do you think about this KTM 300 EXC project bike? Let us know your thoughts in the comments!
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| Before | After |
By Jay Clark