My 07 S4RS has suddenly become rather hard to start. Yesterday morning she fired right up just like always. Thoughout yesterdays ride the bike restarted without issue and ran like a top all day that is until the last two starts of the day. When the the key is turned on, everything powers up as normal, fuel pump, ect. ect.. She cranks normaly but doesn't fire. It takes three starting cycles before she fires however it now takes a blip of the throttle before the engine will jump to life. Once started the engine idles and runs perfectly. She acts the same stone cold or hot.
Since this just started happening yesterday I haven't done any diagnostic work yet but my first guess is that it has something to do with the crank position sensor. Something tells me the ECU doesn't know the engine is cranking so it doesn't send fuel to start. Just guessing at this point.
Any guesses??
cheers
Mike
I'm gonna chalk this one up to a weak battery. After an hour or so on charge the bike cranked over noticeably faster & fired right up. Two weeks ago the battery was too low to crank the engine but it had been sitting for a while so I didn't give it much thought. It's the orginal battery so I guess it's time for a replacement
cheers
Mike
Your regulator/ rectifier may be on the way out as well. Something to check anyway. I had a similar issue of hard starting, charge the battery, and it'd be good for a few days then it'd be dead again. Bike wasn't recharging the battery while it was running and slowly draining the battery. Pretty common issue since the regulator is tucked under the seat and doesn't get enough airflow = fried.
I had similar symptoms last year and a new battery fixed it.