smallest battery to start engine

[Bluethunder3320]

after stuffing a 10hp tecumseh in my mini bike there isnt much room left for a battery. so i am trying to figure out what the smallest battery i can get that is still enough to crank over the engine and start it. what do i have to look for? it is a 12 volt starter so obviously i need a 12 volt battery. but is amperage the only other factor?

i saw online that most small engine starters need 12v and 9-12 amps. so would a 10 amp electric scooter battery do it?


this is in a bike that is probably going to get wrecked a few times and wheelie a lot so it needs to be able to handle that unlike a regular lawn tractor battery it used to have.

 

[HellSpawn]

If the scooter battery doesn't work out, just about any 12v motorcycle battery should do the trick, and they are fairly small.

 

[Bluethunder3320]

i see some atv batteries and sport bikes that are only like 6 amp. but i dont know if thats too low and if i need 9-12 amp.

 

[r_chez_08]

Would a 12ah lead acid like this not do the job?
http://www.ebay.com/itm/New-12v-12A...888?pt=LH_DefaultDomain_0&hash=item483655f390
I dont know what the price of the scooter battery is. If you have one lying around, try it!

 

[r97]

I think this should be a good choice for your battery,
http://www.amazon.com/UTX14AH-BS-YTX14AH-BS-Motorcycle-Snowmobile-Maintenance/dp/B0053Z34DC

Its an Absorbed Glass Mat battery, which means it can be operated in all positions, wont leak, and has a small size. This one is 14ah, which is what my 550 motorcycle has, so i'm sure it would handle your engine. Also make sure your wiring can handle the battery.

 

[Bluethunder3320]

awesome, i saved both links. i think i can make a bracket for the fuel tank on the engine, then actually mount the battery under that on the same bracket. this way i can get the frame done and have more time to worry about the battery (not a huge issue now it has recoil).

tomorrow is time to take measurements and maybe ill find a perfect spot. thanks guys

 

[KieranM]

Nice build man, I use a 12v 7ah battery in my 200cc quad, no alternator hooked up will last over 4 month and still keep 12v, get about 2min of constant turning over before its decides to die. And they are small/ light.

http://www.ebay.co.uk/itm/12-v-7ah-lead-acid-battery-alarms-electric-cars-uk-suppy-70-years-trade-/230717463733?pt=UK_ToysGames_RadioControlled_JN&hash=item35b7d51cb5

 

[Jake.B]

Id go with A QUAD BATTERY

 

[porsche930dude]

honda spree battery is really small and 12 volt. i dont know the exact numbers off hand but i know they can be had at walmart for like 25$

 

[Bluethunder3320]

Nice build man, I use a 12v 7ah battery in my 200cc quad, no alternator hooked up will last over 4 month and still keep 12v, get about 2min of constant turning over before its decides to die. And they are small/ light.

http://www.ebay.co.uk/itm/12-v-7ah-lead-acid-battery-alarms-electric-cars-uk-suppy-70-years-trade-/230717463733?pt=UK_ToysGames_RadioControlled_JN&hash=item35b7d51cb5

unfortunately thats in UK but good to hear 7ah can crank for 2 mins. not sure what a tecumseh starter needs though

honda spree battery is really small and 12 volt. i dont know the exact numbers off hand but i know they can be had at walmart for like 25$

ill look into that now thanks

 

[sideways]

You're looking at the wrong figure guys, 10AH (amp/hours) is meaningless if you're looking for a battery to start an engine.

What you're looking for is a high CCA (cold cranking amps) rating. Buy the battery with the biggest CCA rating that's in your budget.

 

[sexyvicta]

try find an electric start push mower. They have small batteries

 

[sideways]

try find an electric start push mower. They have small batteries

I've got one of those. ^^^ It had an inbuilt plug in charger and all.

It'd turn the motor over for what seemed like several minutes. Bloody good thing it did too, stupid heap of crap Honda copy engine that would never start.......

 

[Bluethunder3320]

CCA

BINGO. you got it. now i need to know what cca my starter needs

actually, i was able to pull start the engine pretty easily. but in order to run my headlight i need a battery because when its disconnected the wires to the lights have no power for some reason

 

[Bluethunder3320]

its here

 

[sideways]

Looking good Blue'.

How much did that set you back?

 

[Bluethunder3320]

Looking good Blue'.

How much did that set you back?

$170 US

motor is a tank though

 

[r97]

That motor looks like it'll have some torque! Are those craftsman feeler gauges? I was using a new set I bought from sears the other day and the .004 didn't fit in the same gap the .006 did. I measured them with my digital caliper and bother were pretty far off.....

 

[Bluethunder3320]

That motor looks like it'll have some torque! Are those craftsman feeler gauges? I was using a new set I bought from sears the other day and the .004 didn't fit in the same gap the .006 did. I measured them with my digital caliper and bother were pretty far off.....

nope its like "general" or something. i dont have calipers but that would be a good idea to check them...

yeah the engine is a torque monster. needs to be tuned but it sounds like it would haul a$$

 

[jman231994]

CCA is good to go off, but if it is an sla it may not be rated in CCA. My friends and I just recently built an electric bike for a schools comp and our batteries had a burst current of 400A each, that was for 5 seconds from memory. At lower draw they would easily provide enough duration to start a smallish engine. In saying that they were 40aH batteries....not exactly small or lightweight, but smaller batteries may have similar specs? Maybe? haha And AGM batteries are awesome. Good luck with this, its interesting to see what is the minimum size wise.