I think the question everyone wants to know, is how does it run? The short answer – great!
Testing the 300’s
Now for the long answer. I have always been a 300 fan. But they always have just a bit of split personality. They run great right off the bottom, are nice in the lower part of the mid, then hit and sign off early. The typical explanation is that they just don’t breathe well.
For someone like my dad, who seldom rides too far into the main jet, they are probably the ultimate bike. However, they have never been the race bike of pros . Over the years, I have spoken with a number of top riders, their typical comment is that the 300 is slow to come on and then hits too hard and signs off too soon. The secret you may not know, is that nearly any 300 KTM or Husaberg that you see a professional rider on in the US, is actually a converted 250, just like our project bike.
Oddly enough, that means for fast riders, the more aggressive 250xc is easier to ride. I found this very true on the last few bikes I owned. While it lacks outright torque, the 250 will rev quicker and typically gets moving quicker than the 300.
Our bike is a wide ratio model and that brings up another problem. The 250 gets caught between gears on the older 5 speed transmission (all the new bikes are six speed). I really struggled with my 2007 250xcw in the desert for this reason. The stronger 300 will cover those gaps better and pull the wide ratio.
I was not sure quite what to expect with our project. Fortunately, I was able to test it back to back with the 2012 Gas Gas XC300 and 2012 KTM 300 xcw. It only took a couple of turns to see that the result is a very pleasant surprise. This package is the ultimate 300. It is stronger off the bottom than the gasser and revs far better than the stock 300.
Now what I had expected was a bike that felt aggressive, something that might be a handful to ride. This could hardly be further from the case. The conversion motor has a great mix of attributes. It is a little softer of the bottom than the stock 300, but stronger than the GG. As the revs climb, the bike feels smooth and strong. It seems to lack a distinctive hit anywhere, just building power all the way. It continues to build steam well past the point where the stock KTM starts wheezing.
Smooth and linear is the best description. It almost feels as if some magic jetting or carb work has been done. It breathes very clean, feeling much like the 250, just beefier. We are running jetting very close to stock 300 spec. By comparison, both of the other bikes felt a little lacking in versatility.
Keep in mind that we are talking about small but significant differences. All of the test riders said they felt pleasantly surprised by the findings, even if it was not exactly what they were expecting.
I am stuck on one point. I cannot tell you exactly why the results are so different from the stock 300xcw. The parts are nearly identical, except for the 2k2 versus 2k3 ignitions of the 250 and 300 respectively. To my way of thinking, KTM should be selling this bike. It is really the best of all worlds.
I also want comment on the Precision Concepts suspension. It is SO smooth, like butter. Both of our comparison test bikes come up short next to this. The stock xcw feels like it has start and stop points in the stroke. The Gas Gas lacks some overall control, it still has rebound issues with the fork. With the Precision Concepts work, both ends are super smooth and controlled anywhere in the stroke. We went with a trail specific set up, so it soaks up everything, but will still do light duty motocross work.
So there you have it, what a fun project this has been. I love the simplicity of working on two strokes. For our scenario, the money spent on the 300 kit made good sense. Our old cylinder and ignition will go to EBay to help recoup a little of the expense. The total bill, including bike purchase, is only just shy of the cost of a new bike (ouch). However, we have something that is completely unique and in many ways better than new. Our 2010 300xcw should see another 200 hours of life with ease.