---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Mon 03/13/06: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:00 AM - Re: 912uls battery for cold starting () ________________________________ Message 1 _____________________________________ Time: 03:00:37 AM PST US Subject: RotaxEngines-List: Re: 912uls battery for cold starting From: --> RotaxEngines-List message posted by: David The starting battery successfully used for our 912 and 912S engines have been selected from the VARTA LF range of motor cycle batteries. The Varta LF range of motor cycle batteries is suited for offroad conditions and is tilt, leak and shockproof - and due to having a fixed electrolyte, it will not leak even upside down. These batteries are also absolutely maintenance free, checking and refilling with water is not necessary. Thes LF batteries have also a very low level of self-discharge, resulting in a long service life. But it is the low internal resistance that makes the LF range attractive for home-builders using the 912. This is due to the fact that the LF range test starting currents exeed those required by the DIN and EN industrial norms. Varta LF type 508-901-015-3104 12V, 9 Ah, 200 amps cold cranking current Varta LF type 511-901-014-3104 12V, 11 Ah, 220 amps cold cranking current Varta LF type 518 901 026 3104 12V, 18 Ah, 260 amps cold cranking current Even a still smaller LF battery is capable of starting your Rotax. A LF battery of only 6 Ah (amperehours) capacity has been used with success as a starting battery for a 912S, but this battery was installed mainly for weight reasons and a higher Ah capacity is recommended. All these batteries exhibit unusually low internal resistance resulting in a high starting current resulting in enough rpm to ensure quick startup of the 912 engine, and thus minimizing mechanical shaking. It is also well worth to install the heavy duty Rotax starter, but you might already have one as the 912S engines now are delivered with it. VARTA is just one quality manufacturer, well known in Europe, there must be others in US with the same kind of specifications. Just go for the lowest internal resistance, to provide more than 200 amps of cold start current. regards Max Electrician for several 912 equipped homebuilts, including my own > -----Original Message----- > From: owner-rotaxengines-list-server@matronics.com > [mailto:owner-rotaxengines-list-server@matronics.com]On Behalf Of ext David X > Sent: Monday, March 06, 2006 6:56 PM > To: rotaxengines-list@matronics.com > Subject: RotaxEngines-List: Re: 912uls battery for cold starting > > --> RotaxEngines-List message posted by: "David X" > There are several VARTA models. Can you recommend a specific model? > > -------- > Zodiac 601 XL - CZAW Built - Rotax 912S