S4 wont start in cold weather

[944]

My S4 wont start if the outside temperature is below 5'c. It turns over slower than usual then stops when I use the fast idle or open the throttle ( increased compression)

The battery is a GS and fully charged. I got the AA to test it under load and it all checks out OK.

If I put a heater under the bike for an hour it starts fine.

Any Ideas for a battery that will fit but has a higher cold cranking ability?

Mike

[Phatty]

check the battery earth where it joins the crank case. mine was loose

[944]

New Varta battery, starts easily in -3'c.

Original GS battery checks out OK but goes not have high enough CCA in this weather.

Mike

[dunlop0_1]

Does the S4 have a air temp sensor like the 748? could be faulty.

[jerry]

How old is the battery if nearly 3 years or more replace as they dont give full amperage as they age.

[Duke John]

Have I picked up that you have fitted a new Varta battery and it is Ok?
If so great, was gonna say make sure if you are replacing the battery that you do get an original Ducati one, or a Varta or Unibat (now OE suppliers to Ducati).
These 3 types all look identical in how they're made suggesting they're from the same factory.
Some of the the "low cost" batteries aren't that good (crap actually), I've seen a few that have caused issues with starting from new.
You're original battery could have been a gel type too, they tend not to last as long as the later sealed acid type.
Watch too for these batteries leaking acid, I've seen this on a few monsters and it can dribble down and spoil the engine paint. Never a massive leak but a shame all the same.
Good luck
Ducati John
www.ducati-john.co.uk

[944]

Yep, new Varta to replace the GS......fixed

12 amp hour instead of 10 and 190 cca, some of the other sealed batteries are only 90 cca

Mike

[Easy]

I've had the exact same problem with my s4r, bought a techno battery for40 pounds & now in the cold weather the bike will only start if I put a heater on. Since I mainly use it in the summer my question is will this battery be ok or should iinvest in a more expensive one?

[944]

I only had problems below 5'c

No problem in the summer

Mike

[dunlop0_1]

Like i said, air temp sensor!!!!!

[944]

I don't think a temperature sensor will stop the engine turning..........unless its been sucked in.

Mike

[dunlop0_1]

Like i said, air temp sensor!!!!!

Sorry, red wine had took control. LOL