Battery voltage query

Hello all, a general question here.

I was just wondering if people know what the minimum voltage the post 2004 RSV's (if they're different to the pre '04 ones) need to start? Reason being that I'm not riding mine much and I think I'm going to find out the hard way very shortly what voltage won't turn it over!

I went for a ride the other day for the first time in two weeks and out of interest I checked the voltage trip and it was reading 11.9 volts which seemed a bit low but with a slight splutter it started and then read 14.2 volts when running which seemed ok. However I was a bit confused when after a 50+ mile blat during which I apparently averaged 33mph and that included going through 1 city and 3 towns both ways (at the speed limit) my voltage trip was reading 12.3 volts with the engine running and 11.7 with it off.

This seems a bit odd to me as I would hope a trip like that would charge the battery not drain it! I saw in the manual that the battery will only be charged at 4000rpm or over and with that in mind I rarely went below it and I didn't use the main beam at any point either. Plus I don't have an alarm sop that's obviously not an issue.

Can anyone shed some light on this for me as it doesn't make sense to me? The bike was brand new in September 2008 so I would hope nothing's faulty on it but I guess you never know.

sergi75 said:

I have a 02 and my readings are very similar to yours, the bike's got an alarm and that drains the battery. The drop in V after 50m might have been because you checked it when the fans were on to cool down the engine.

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Ah, thanks for that I didn't think about that, although I did check it again after it was off and it read about 11.7.

Thanks for the input none the less.

fusebox said:

hi fella!
im sorry to hear about your charging issues, not the norm with these bikes in general. Anywhere between 12.8- 14.5 are good what i would consider to normal charging perametres with the lights on or off, with the engine running!

without the engine runing around 12.3- 12.8 i would consider to be normal if the baterry is in a state of readyness, that is charged ready to go!

please recheck you figures with a multimetre rather than the dash as this isnt very reliable, in my experience , and i 'll work through the checking proceedure with you to sort your problem! if you give me the figures

1. engine not running
2. engine started lights off
3.engine started lights on

please check these with a seperate multimetre pls and let me know!


cheers
griff

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Thanks for that. I'll give it the once over and get back to you asap with some figures, however the only problem is my pc is down so I'm currently at work using there's and it's a bit hit and miss when I can get on the forum.

Also something I wanted to clarify with you is that I don't have the option to turn the lights off on mine as I'm guessing the post '04's did the "Automatic Headlights On" thing as most manufacturers did around that time. Subsequently did you want me to do it with the main beam on and off or just literally engine on, engine off? Sorry if I'm being thick but I like to know exactly what to do if possible.

Thanks for your time. :thumbup

LEGS said:

Rage, just following on from from Griff's post, there are numerous other posts on this site about keeping RSV and RSVR hooked up to Optimate battery conditioners when bikes are not being used. Batteries need to be kept in tip top condition due to the high cranking amps needed to turn over a high compression V twin. If your bike has an alarm fitted and is left standing even for a few days then the battery voltage can drop. Problems with sprag clutches then arise from owners trying to start bikes with low or week batteries. Buy an Optimate 3 or 4 and keep the bike hooked up.

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Cheers LEGS. Deep down I know an optimate is the way forward but I am so skint at the mo I really can't afford to get one for at least a few weeks at the earliest but I know if I don't get the optimate I'll spend alot more in the long run replacing countless batteries. Doh!

However all is not lost as fortunately one of my best mates has one he can lend me for a bit which is bloody handy all things considered.

Also aside from keeping the bike going I really wanted to just run the issue past you guys (yourself, Spoonz, & Grif among many others) as you seem to be the closest thing to RSV guru's and you know what's what so it's reassuring to hear it's fairly typical and not a problem as such. Thanks for your time and advice. :thumbup

P.S Forgive my massive mechanical ignorance but what exactly is/are sprag clutches? I've heard the term many times but can't say I really know what one is or indeed what it does. Thanks again.

fusebox said:

hi fella!
im sorry to hear about your charging issues, not the norm with these bikes in general. Anywhere between 12.8- 14.5 are good what i would consider to normal charging perametres with the lights on or off, with the engine running!

without the engine runing around 12.3- 12.8 i would consider to be normal if the baterry is in a state of readyness, that is charged ready to go!

please recheck you figures with a multimetre rather than the dash as this isnt very reliable, in my experience , and i 'll work through the checking proceedure with you to sort your problem! if you give me the figures

1. engine not running
2. engine started lights off
3.engine started lights on



please check these with a seperate multimetre pls and let me know!


cheers
griff

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Right as I don't have the option to turn off my lights on my '08 RSV I've done the following;

Engine off (before 15 mile ride) 11.6 Volts.
Engine on (as above) 13.0 Volts.

Engine off (after 15 mile ride) 12.1 Volts.
Engine on (as above) 13.9 Volts.

I'm think I'm still gonna get an optimate but all seems fairly reasonable to me, although I'll be grateful for some input if people have any info to add.

Cheers.

A303 said:

Hey Rage.
There's those that know a lot more about 'Prillas than me on here but as I've recently become intimately acquainted with sprag clutches let me enlighten you.
Because RSV engines are such a lump to turn over (as opposed to a dinky Jap IL4), the starter motor works on the crank via a series of reduction gears. On the back of the flywheel is a one-way clutch - basically a set of weird shaped bearings that only grip one way - which allows the starter to turn the crank and then disconnects it by freewheeling once the engine is started and the crankshaft starts spinning.
They are a weak point on RSVs but only if you persistently try and start it with a marginal battery. If your battery is tip top and properly charged then you shouldn't have any problems.
Hope this helps.

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Cheers mate, that was a bloody great explanation on a level and in terms I genuinely understand. Thanks again A303, that was spot on! :thumbup

fusebox said:

to be honest mate those figures seem good to me! sorry to say fella i think the optimate is the next option for you!
hope this helps mate!
griff

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Thanks for your input Griff, it's always reassurring when a clued up chap like yourself gives the thumbs up. Optimate it is then. C'mon santa you can do it!