Needing some help. I bought a 2011 Dyna Street Bob with a stage one a couple of months ago. Everything was fine at first, but now after it warms up it seems to have some issues wanting to start. I push the start button and it turns over but it just huffs and puffs. I have to release the start let it sit and try it again. Does anyone have any ideas what causes this?

 

I would start with new plugs, wires, and check the resistance of the coil after bike is warmed up good. Resistance should be 2.5 to 3.1 ohms, if I remember correctly. Look it up though.
Coils tend to give problems when hot when they start to fail.
Since it ran fine at first, I doubt it's the tune.

 

How old is your battery? cables clean?

 

I'm not sure how old the battery is but it looks alright and so do the cables/connections

 

You're kidding, right?

 

No... why?

 

I think they’re getting at the fact you can’t know the health of a battery by “looks.”

I don’t know what “huffs and puffs” sounds or looks like, but I’ve had similar warm/hot start problems with the same bike. When the starter is hot it is less powerful, resulting in kick-back. A stronger starter clutch can resolve the problem. Also replaced my compensator with the SE version at the same time. Problems solved.

 

I understand that you cant test a battery by looking at it. What I was getting at is that it doesn't look old and I have not had the chance to have it tested

"Huff and puff" as in the motor is going through it's full cycle with the starter but without fire. So it builds up compression and then exhausts it. It makes a repeated "puffing" sound from the exhaust. And it continues until I let go of the start button and try again


Unfortunately I fear starter clutch and compensator may be out of my mechanic skill level.

 

If the engine is turning over and making compression and goes through multiple compression cycles without stopping as long as you press the starter button, then it's unlikely the battery has anything to do with your problem. (or starter clutch or compensator).

In addition to compression, you need fuel and spark. Do you smell gas after extended cranking? Check for spark by pulling a plug wire and plugging it into a spare plug. Rest the metal shell of the plug against the cylinder and crank. Look for a strong spark.

And/or, pull a spark plug out and see if it is wet or dry, or fouled.

Don't try this at home, but, we used to take a lit match and hold it over the plug hole. Just be sure your hand is not in the way of the flame jet that may ensue... (One of those fancy newfangled barbecue lighters might be a better idea.)

 

CKP sensor might be bad. You can test it with a digital multimeter easy. Just follow the wires to the plug.

You can find a procedure on axleaddict.Com. Sorry can't seem to paste the full url on this tablet.