2005 DR650SE Start/Throttle issues
 

• 2005 DR650SE 5500 miles
• IMS 4.9 gallon tank
• No other mods that would affect the current issue.

So, after a five day hiatus in the Mtns of CO last week I let my bike sit for a few days. When I finally got around to starting it again it was very hard to start and when it did finally turn over it was a rough few seconds at first sputtering around and all. After a bit it idled fine and everything seemed ok. That was until I took it for a little spin. I noticed that getting on the throttle in first or second would cause the bike to bog out and almost stall almost as if it had water in the tank, but it does not.

The history is it ran fine until I took it to CO for five days of high altitude riding. I notice at altitude (10k +) it was very sluggish, and as the days went on i noticed it was a bit harder to start. When I say harder I mean that I had to give throttle to get it to turn over when I have never really had to do that before.

I do notice a light ticking sound and maybe this indicates I need to adjust my Valves. I have heard people talking of the float adjustment in the carb but I do not know the reason this is done or the symptoms of it needing adjustment. I think my issue is carb related but just what is wrong with it is beyond my scope at the moment.

I have a K&N Airfilter comiong in tomorrow so I will put that in. I do not think my airfilter looks dirty at all but maybe it is clogged up. I hope it could be something that simple.

These are my issues...

If the bike is not spinning over fast enough it could have a weak battery or a loose connection. When I got home from Colorado mine would not turn over. It had a loose connection on the battery.
Another thing that will make it hard to start is to haul the bike with the fuel petcock turned on. Mine has a manual petcock and will flood if hauled with the gas turned on. If your petcock is controlled by vacuum, never mind.

Just a thought as I have no experience with the DR650 .
Your bike will have been running rich in the mountains , maybe the spark plug[s] are fouled - some bikes are very sensitive to this .
Your air filter could , as you say, be clogged .
Try the bike briefly without an air cleaner element and see if there is a difference .
Look for the simple stuff before you start pulling the carb apart .

Blockage??
 

And if Patrick's advice doesn't work, I suggest you have a look at the carb. The symptoms you describe also point to the low-speed jet being blocked. I have never used Techron (not available on this side of the planet) but it may help clean this out. Otherwise blow out the fuel galleries with compressed air. DON'T poke things up the small jet. Its size is important and damaging it with wire or something like that is not a good idea.

Carbs are pretty easy to get into and put back together, if you never have before. The biggest risk is losing small bits. If you have a digital camera handy, it's a good idea to photograph the carb as you pull it apart. Never force anything. If it doesn't go back together easily, something it wrong.

Regards

Nigel in NZ

As suggested - gunk in the carb can cause the problem. As mollydog sugests - use the drain screw and see what comes out ... if it is even a little water/dirt then a complete carb clean is indicated.

If you have a clean carb .. then I'd look at the exhaust valves closing up .. this can cause difficult starting .. how long since the valves were checked?