I've found some info on this but not much help I replace plugs and caps didn't seem to do anything. Can't find anyone in the area to work on it (Atlanta GA.) It's a 2010 with just over 8000mi. I got a Honda for reliability. Can anyone help?
When warm or stop and go, runs ruff no power.
- Thread starter Brownz NT
- Start date
Typically these symptoms are caused by the original faulty spark plug caps but you advise you have replaced these.
My next thought is fuel or fuel pump.
The other common problem that may be the cause is the crank position sensor but typically the symptoms for this problem is that the engine will not start when hot.
If it was my bike the first thing I would be doing is checking all of the electrical connectors under the seat (unplug and re-plug) as it could just be a bad electrical connection.
Seagrass
My next thought is fuel or fuel pump.
The other common problem that may be the cause is the crank position sensor but typically the symptoms for this problem is that the engine will not start when hot.
If it was my bike the first thing I would be doing is checking all of the electrical connectors under the seat (unplug and re-plug) as it could just be a bad electrical connection.
Seagrass
It runs very well until it’s warm typically stop and go cycling with the radiator fan.
I’ll give that a try
Crank position sensor is failing when warm/hot
DirtFlier
Site Supporter
If you're going to the trouble of finding relevant connectors, don't just unplug them and replug them. I always blast both sides with electrical cleaner (NOT WD-40!) then apply some dielectric grease in the sockets. You might as well do it right! 
I was alerted to this product on the 3rd Gen Magna forum and picked up a can last summer. I've been using it on projects or anytime I'm chasing electrical issues. I spray it on both ends of the connections then plug and unplug a couple of times. I have not done any scientific testing but I haven't had any electrical issues after using it and connectors are much easier to plug and unplug after using. My brother was having issues with his trailer yesterday and I used it on the plug and the base of the bulbs and the lights were noticeably brighter. I did actually buy this at a local guitar store:
Deoxit D5
Deoxit D5
Warren
2
I guess anything is possible but it’s surprising to me that the crank sensor would fail with just 8,000 miles on it.
I had something like that back in '10 not long after I bought my first NT. The dealer replaced the regulator/rectifier and it never happened again. Closest thing to it was when my fuel pump failed at about 115,000 miles.
WVRider
Site Supporter
Sure sounds like what mine was doing and was cured by putting on a new set of Spark Plug Caps.
What kind of caps did you use to replace yours?
WVRider
Site Supporter
Actually picked mine up at the local Honda dealer. They are specific to the bike and are available in other brands. Places can cross refference.
This link should have the 3 page service bulletin about replacing the spark plug caps. Part number 30700-MEW-922
Thank for all the suggestions so far nothing has worked not sure where
to go from here thinking about putting on a dyno. Perhaps something can be detected that way.
to go from here thinking about putting on a dyno. Perhaps something can be detected that way.
Exactly what was called for in this
Your issue does not seem common so I'll throw this out there. Anything been done to the valves or checked the clearances?
Since it seems temperature related it could be possible a valve is too tight and when it gets hot expands, the clearance goes away, and then the valve never closes on it's seat.
This is a basically a longshot but if you have carefully checked the stuff suggested here it may be another thing to check to verify that it is not the issue.
Good Luck
Arknt
Since it seems temperature related it could be possible a valve is too tight and when it gets hot expands, the clearance goes away, and then the valve never closes on it's seat.
This is a basically a longshot but if you have carefully checked the stuff suggested here it may be another thing to check to verify that it is not the issue.
Good Luck
Arknt
I'd be inclined to second this idea. When I purchased mine a couple years ago with about 21,000 miles on it, I discovered a problem. The bike started fine and ran fine, but when I got into stop-and-go traffic where the engine got hot enough for the fan to start to cycle, the engine would buck and miss. When I got back to open traffice everything was fine again.
As a hunch, I adjusted the valves and that cured the problem completely. Adjusting the valves is a pain, but that just might be the cause.
Cliff