Slow, weak cranking? New battery, so??

[fjrfanca]

08 Gen II was getting a bit hard to start, with gradually slower cranking a few years ago. I replaced a battery with a fresh lightweight li type, and it surprised me how fast the starter cranked. Fired up FAST. So now a few years later, seems like it cranks slower again, same basic symptoms. Decided to replace battery, even tho superficial testing showed good voltage.
I bought the same model Li battery, expecting similar results, and it SLIGHTLY improved things. It does start, but it feels like the draw on the battery causes the starter to slow down. I carefully charged the new battery per instructions first.
It has me thinking of other things, such as issues with wiring, the starter itself, etc. Any ideas where to check / look next? Thank you in advance!

 

[escapefjrtist]

With machine age and if you have a ton of miles on the bike, it's possible the starter is getting tired. What happens is the starter seal begins to weep oil with subsequent contamination of the starter itself. To confirm, check starter amp draw, IIRC is normally less than 80-90 amps. While you're at it, starter relay should also be checked, item #5 on parts fiche.

Good luck!

~G

 

[RossKean]

Unless there is a really good reason to suspect the battery, I would always get it load-tested before replacing it.
Good check for the starter is to measure the starting current with a clamp-on DC ammeter. Bad starter may be well north of 100 amps.

 

[Rocnsanman]

I'm inclined to think you have a starter issue. A friend of mine had a bad starter that exhibited the same symptoms. As Ross has suggested a clamp on DC Ammeter should tell the story better than guessing. I doubt the starter relay is bad but a replacement is easy to do and inexpensive. Good luck

 

[fjrfanca]

Thanks guys. Let me amend the Q a little bit. Starter turns fairly fast for just a split sec, then winds down almost to the point it wont start bike. Does that change any opinions?

 

[RossKean]

Thanks guys. Let me amend the Q a little bit. Starter turns fairly fast for just a split sec, then winds down almost to the point it wont start bike. Does that change any opinions?

Not really. Get the battery load tested if you want to confirm it is good - not a guarantee, even with a new one. As I mentioned before, check the current draw when trying to start as well as monitoring battery voltage while starting. Very high current means the starter is FUBAR. They can be be rebuilt.

 

[John Scottorn]

I'd check the wiring as well just to be sure. Are all connections good and clean after the battery etc?

 

[Prosolar]

If the starter is drawing too much current it will pull the voltage down on the battery pretty quick.