In the morning when I go to start, my bike doesn't want to start up right away ... it'll crank for 5-10 seconds before starting ...

The weird thing is that if I stop cranking and then try again, it will frequently hit off right away ...

Some background ...

'05 Dyna with 95" SE big bore cast flat top pistons
SE Performance MCR heads
Andrews TW37B cams
SE 1.725 rockers on the intake side only
Paughco 2-into-1 exhaust w/ 22" goose cut muffler
Goodson A/C with Sifton breather bracket
(I replaced the cam chain tensioner shoes when doing the cams)
Replaced the stock ECM with a ThunderMax w/ AutoTune unit

All of the above was done around 22-24k miles ... currently almost 60k miles on the clock ... so almost 35k miles on the build ...

Over the past few months (over the late fall and winter) it has been acting like this (i.e., cranking excessive at start up) ...

It does this whether the morning temp is 45 degrees or 62 (morning temps haven't been much above that range over the past few months ... probably a little cooler a few mornings) ... almost never exhibits this pattern in the afternoon ... or once the bike has warmed up a little (doesn't take much ... ride three blocks to get gas and shut down ... restarts right up) ...

I replaced the battery about 6 weeks ago ... then, just a couple of days ago I replaced the spark plugs with NGK DCPR8E gapped to 0.035" ...

Alright ... what's going on ...?

Thanks in advance ...

R/
'Chop

 

Your spark plug gap should be .038 to .043.

 

Have you checked the internal fuel line for a pinhole? It can cause that kind of starting problem.

 

I know you replaced the battery but the problem sure sounds battery related. Even new batteries can have problems. What battery? Is it always on a tender? I would load test the battery first, if for no other reason than to eliminate that as the possible source of the problem. Also, check battery connections and all ground connections.

If that's not the problem check for good cable function and adjustment and clean the IAC plunger and bypass port.

 

Stock replacement battery ... I'll check the connections ...

I am TAD and living at a hotel for a few months so haven't used a tender for quite a while ...

The plugs I replaced were E3.36 plugs that looked pretty good soft light tan color and hardly any residue on the electrodes ...

IAC does sound like a good lead ... I'll check it for possible debris, etc ...

I am smelling gas from the compression releases ... so, it is getting fuel ....

THX for the troubleshooting ideas ...

R/
'Chop

 

I am doubtful that a 3 to 8 thousandths difference in the gap would cause this issue ... I would also say my 35 thousands was a little 'generous' ... closer to 36 or 37 ...

I thought the issue was mitigated depending on whether the tank was full or empty ... also, as noted above, I am getting fuel smell ... I am pretty sure the fuel pressure is good ...

 

You could be getting too much if the IAC step motor is sending the wrong signal to the ECM on startup. I am not proficient in how to test or check that but know it can cause cold start and rough running problems.

 

I checked the IAC program using the ThunderMax link to my laptop and actually did an IAC Auto Calibration ... however, if there's debris in the bypass port it might not only affect the starting, but the calibration might be off as a result, as well ...

I had also checked the Diagnostic Code on the TMAX and not getting anything there...

IAC is definitely something I am looking in to ...

 

djl

Think you might have been on to something with the suggestion WRT the battery ...

A couple of days ago, I noticed some strange color of grey 'dirt' on the side of the battery and wiped it off ... then, this morning, noticed some more in about the same place ...





I am thinking maybe there is a crack or pinhole in the case of the battery ...

I just got the thing less than two months ago ... hmmm ... around the time I started having issues ...

* * *

Edit: well, the battery checked out okay ... guess that is not it ...

R/
'Chop

 

Follow up (or variously, a 'zombie' post) ...

Started getting the problem back as the weather got cooler up here in the Puget Sound ...

So, finally decided to replace the starter with an All ***** 1.4kw model 80-1001 starter ...

I had entertained the idea, back when ... now, in retrospect, I should have done this over a year ago ...

Oh well, working like a champ, now ...

R/
'Chop