Ec300 dualsport vs ktm 500exc

[roverhybrids]

Anyone have thoughts on building an ec300 as a dualsport? This would need to be comparable to the newer ktm/hisky/gasgas 500 4-strokes I have a 2001 ec300 engine as well as a counter balanced engine

 

[farmerj]

Not a good idea, a competent dualsport needs to be a four-stroke. If you're just connecting between trails for a mile or two on the ec300, no problem. But the fueling isn't smooth enough for street riding for any significant amount of time. Just go out for a ride. Something like the KTM 500 is in a different league for DS use. For tight single-track, yes - a 300 2T.

 

[coopernicus]

I use my plated 2018 300 (stock gearing) for dual here in Colorado and it works well as long as you keep speeds below 50 mph for any sustained riding (I periodically press kill switch to give it some "richness") and distance of less that 10 miles on pavement. Those are the upper limits in my opinion. I've gone faster and longer but I generally stay below 40 mph on my forest road/trail rides and I can ride a hundred miles a day like that. One thing to remember with a 2 stroke with riding faster and longer is that the exhaust has little droplets of oil in it that will stain whatever you are wearing at higher speeds as it seems the aerodynamics makes the exhaust "curl back" into your body.

In sum, if you are serious about dual sporting with significant miles on pavement, you need a 4 stroke. I always truck/trailer my EC300 and only use pavement as a last resort for connections. My solution is to have both as I have an ATK 605 that rarely gets used as I don't like street riding. Good luck with your decision!

 

[roverhybrids]

Ideally:
Maintain speed of 50-60mph
Handle 1 hour* of continuous pavement
Not blow up!

Pavement will be avoided as much as possible. No interstate. 1 hour is hopefully worst case and not the norm

 

[coopernicus]

Ideally:
Maintain speed of 50-60mph
Handle 1 hour* of continuous pavement
Not blow up!

Pavement will be avoided as much as possible. No interstate. 1 hour is hopefully worst case and not the norm

I would never do that with either of my 300s. I had to ride my 2014 EC300 for 15 miles of 60 mph highway with a group of others and we kept it at 55-ish and the 2014 had the stock choke lever on the handlebars. I tapped that lever every 5-10 seconds to keep it from seizing. I don't want to have to do that again! Stick with the big KTM 4t.

 

[roverhybrids]

I would never do that with either of my 300s. I had to ride my 2014 EC300 for 15 miles of 60 mph highway with a group of others and we kept it at 55-ish and the 2014 had the stock choke lever on the handlebars. I tapped that lever every 5-10 seconds to keep it from seizing. I don't want to have to do that again! Stick with the big KTM 4t.

Is that really necessary? How do 2-stroke scooters and street bikes survive?

And if it wasn’t clear I have zero experience riding any dual sport.
The most likely occurrence would probably be when I have a limited amount of time before dark, say 2 hours and the ohv park is 15-20 miles away I have always transported my bike there

 

[coopernicus]

It is necessary for the 300 if you have it jetted/tuned for riding trails for which it was intended. Enduros and motocrossers are jetted/tuned/geared for slower but more "sudden" obstacles where we want responsive power. Scooters and 2T street bikes are jetted/tuned/geared to be ridden in a certain RPM range to try and prevent seizure at a constant RPM. Additionally, they typically use an oil injection system to provide directed lubrication.

I would love to be able to ride my 300 on major roads but to do so would mean it would not be effective or fun on the trails. I would have to find sprockets to give me more top end speed, I would need to richen up my jetting across the board, and I would have to alter my ignition timing to make it more effective as a road worthy motorcycle. In lieu of that, I choose to keep my speed down, avoid major roads, and tap the choke every now and then while on open roads to richen up the mixture.

 

[roverhybrids]

Would a lectron Carb help? Click it a few clicks richer for the street?
Modified(?)choke circuit with cable ?
Richer fuel/Oil mix?

What would realistic exceptions be?

Anyone with experience seizing a 2-stroke on the pavement?

 

[coopernicus]

Had an older Lectron and hated it as it totally flattened the power. Newer one does have some adjustment on Power Jet so that MAY help prevent a seizure during extended street riding.

Modified choke circuit with cable: That MAY help but it's a stopgap and not a solution.

Richer fuel/oil: That MAY help a little but you should stick to mix/ratio recommendation by manufacturer.

Realistic expectations: I guess I wasn't clear, I hate everything about riding my 300 on the street above 45mph. Everything. Vibration, worrying about seizure, sucking down fuel. I have only gone more than a couple miles twice: one mentioned above for about 15 miles and another for about 7 miles (this was thankfully on a 35 mph road). We were running out of daylight and had to take the roads. I've been dual sporting for years and my ATK 605 4 stroke is a lot better for dual sporting.

Experience with seizing: Yes, 2 of my brothers did this multiple times in the past on different 2 stroke dual purpose bikes. I know other guys over the years who have done this. It's a real thing.

Ultimately, it's your choice. The risks have been outlined. I made my 300 street legal just to connect small county roads in our mountains and it works fine for that because we rarely get above 40 mph for a half mile at a time. I hate it with a passion when riding on faster pavement for longer distances. A 4 stroke is far better for that. Good luck!

 

[roverhybrids]

Thank you for the replies
The answer could be staring me in the face

As I bought the bike with a blown engine!

I haven’t pulled it all apart yet but sounds like a bottom end crank bearing. Piston looks fairly worn. Cylinder looks good, but maybe previous owner cleaned it up first