battery

Dodgy Kips motor? CDI? battery? diode? reg/rect? its all gobbledygook to me but some people understand it ask tham a question here
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the_bard
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Joined: Sat Mar 14, 2009 8:38 am

battery

Post by the_bard »

so i was thinking in terms of weight saving for track; motorcycle batterys are really heavy, now on the track the only electrical things on the bike is the ignition system the tach, the kips valves and the oil pressure light right?
so what i was thinking was could you replace the battery with 8 rechargable AAAs? it would still provide 12 volts and because there are no lights to run, obviously no starter etc there should be enough amp hours to run the bike and you would save over a kilogram i'd estimate...
any thoughts?
Bikemike
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Post by Bikemike »

I actually tried this, although with AA rather than AAA batteries, still loads lighter than a normal battery but about 3x more capacity than AAA.
I bought a 10 cell holder from ebay for a couple of quid (you need 10, not 8, because rechargable batteries are 1.2 volts, not 1.5).
Image
Filled it with NiMh batteries from Aldi (total cost £8.00)
Image
Upgraded the connections on the battery holder and popped it in the battery holder to compare- it looked a little lost!
Image.

It powered the lights quite happily and the bike started and ran ok.
BUT- for some reason the bike wouldn't charge them. No charge went in and the regulator (a known good one) kept voltage down to only 12.5 volts (should be 13.8-14v).
I took it off, put the standard battery in and hey presto- 14v and a good healthy charge. Don't know why it didn't work but I wasn't going to risk blowing the regulator.
I imagine it would be ok on a total loss system, but I didn't want to risk it on my road bike.
If you try it, let us know how you get on.
Need Break down cover? P.m. me.
the_bard
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Post by the_bard »

hmmm
firstly glad to see someone else has come up with this idea, don't want to be the only crazy one :P
must have something to do with the charging cycles of the different types of batteries, lead acid batteries can take quite a few amps of charging, whilst the smaller nimh generally need a trickle charge so maybe the voltage couldn't get through, i agree good move don't want to bust your regulator. i would hazard a guess if you wanted to do this properly you would have to remove the charging system on the bike and replace it with a butchered nimh charger or somthing... or like you said if it's just for track take the charger off and replace the batteries with single use ones each session would only cost about 2 bucks a pop, you'd probably save that on fuel/ oil for not lugging the massive battery around lol.
TwoStroke Institute
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Post by TwoStroke Institute »

Current draw :roll:
crochet & croquet
Luders
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Post by Luders »

All I run on my race bike is what we call a battery eliminator. I bought mine from Rex's Speed Shop and all they basically are is a capacitor, which holds the charge.

Simples!

http://www.ebay.co.uk/itm/Tzr250-Nsr250 ... 415efcf237
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