2012 So Cal National Hare & Hound, Mark Kariya photo
It has been a while since we talked about the long term 2013 350exc. Total time on the small dual sporter is 120 hours now. We get lots of inquiries about the durability of the 350, so I figured it would be interesting to do a tear down and see how it is holding up.
For much of the past year this has been my primary ride. For Baja I have split time between it and the old 525exc. They are an interesting contrast to each other; one is big and heavy with lots of great power, the other is light and agile with sufficient power for most situations. The 350 does surprising well for long days of riding. It is never tiring and as long as there is not too much deep sand, it holds its own quite well. With the Seat Concepts seat and 13l KTM tank, it is suitable for even the longest days.
Our riding has included two National Hare & Hounds, a couple of district enduros, four trips to Baja, countless days at the moto track and plenty of dual sporting around San Diego County. As it is not a real powerhouse, it has spent much of its life with the throttle pinned wide open.
One of the amazing things is how little it wears parts. It still has the stock chain and sprockets. They don’t even show much wear. The oil always looks surprisingly clean, even after long trips. It is very stable. I used a Fastway stabilizer for a few of the desert races that I ran, but for normal trail riding it isn’t really needed.
Here is the list of mods that I have done:
Stiffer springs front and rear (.44 front, 7.2 rear)
Seat Concepts seat
KTM 13 litre tank
Renthal Titanium grips
Bullet Proof Designs swingarm protector and disc protector
Sicass racing map switch
The only performance modification is the European 350exc fuel map. The bike still has all the stock emissions equipment.
All of the dual sport lighting is still functioning. I broke one turn signal during a National Hare & Hound, I think it melted from heat. But the replacement has lasted now for nine months. I typically use the stock headlight, but it is not very powerful. For any real nighttime riding I put the Baja Designs Squadron on. It is a plug and play application, no wiring or electrical system changes required.
In the back I have cut the stock subfender off to keep it from getting caught in the wheel. I removed the license plate light and moved the plate up so the bottom holes mount in what were the top holes. This moves the plate right up to the tail light, letting me remove about 5 inches of the stock subfender. You can hardly notice the change and the license plate is up high enough to stay damage free.
The bike has had two mechanical issues. It developed a water pump leak at around 100 hours. I replaced the outer seal, but that did not cure the problem. After discussing the problem with KTM, we came up with two probably causes; the first was wear or corrosion on the water pump shaft. This is a replaceable sleeve and fairly easy to change.
The second possibility could have been the head gasket. Apparently there have been some cases of pressure leakage from the cylinder to the cooling system, this pushes coolant past the water pump seal. Both of these symptoms were addressed during the rebuild of the top end, so we may never know the exact cause.
Our other mechanical issue has been chronic since the bike was new. The 350exc does not cold start well. Initially we assumed the problem would cure itself after break in, but that was not the case. Apparently this is a rare case, but there are other 350’s that I am aware of that suffer from this. KTM inspected the bike at 30 hours and swapped a few parts to see if they could cure the problem, but it made no change.
I have been living with the issue long enough that I don’t even think about it. It is pretty much the same as all RFS bikes were on cold mornings. I have figured out the technique to make it cold start okay, it involves kicking and hitting the starter button at the same time while giving a slight amount of throttle. If we did not have the kickstarter, it would be a real problem. By comparison, our 2014 450xcf will always start instantly at just the slightest touch of the button.
KTM did the teardown for us. As you can see in the photos, the top end looks like new. There is very little sign of wear. We installed new rings and gaskets and put it all back together. At 120 hours the valves were still within spec, having never been adjusted since new. I have one quick ride on the 350 now that it is back together and everything feels good. It is probably ready for another 120 hours of abuse.