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BRP starting issues

Posted: Wed Jan 15, 2020 5:28 pm
by Laoch
I'm working on my Son's BRP and he's always had issues with the thing slow cranking, it usually fires. But it sounds like it's killing the battery just trying to turn over. It as a newish agm battery, but I think it's time for a new one.
Do big thumpers usually turn over slow?
The current battery is rated at 120 cca, which seems low to me.
I don't want to spend big $$ on a Lithium battery without knowing if there is an underlying issue.
I've checked and cleaned connections.
Stator puts out 180w -when new. That also seems low.

Re: BRP battery

Posted: Wed Jan 15, 2020 6:01 pm
by Skinny-J
Could it be the starter motor is going bad? Or the bendix is binding? I have seen that cause slow cranking with perfectly fine batteries...

Re: BRP battery

Posted: Wed Jan 15, 2020 6:09 pm
by Skinny-J
Most of the batteries I am seeing spec-ed on interweb for a 650XRL are 120 CCA. I even see some lower. You could go up a little more for some more money though...

Re: BRP battery

Posted: Wed Jan 15, 2020 7:31 pm
by smdub
Jump start it from a car/truck (that isn't running.) If it cranks fast the battery is weak.

Alternator wattage isn't that big a deal as long as it 'enough'. Test the battery voltage when the bike is running. Should be at least mid 13V.

Disclaimer: I charge batteries for a living. I've designed solar powered chargers for 20yrs. So I might know what I'm talking about. But I could also be full of s***.
Lead acid (esp AGM) is sort of a crappy battery to start vehicles with. They just aren't efficient at delivering a lot of joules at once. This is where Lithium shines. Your AGM battery is probably 12Ah? A replacement Lithium will be ~2Ah and will still deliver more than twice the starting current - even until its right on the edge of dead. That said, with only 2Ah of real capacity don't leave the lights on when stopped. Or try to crank and crank and crank to clear a flooded motor. Lithium don't really self discharge either. So come springtime your bike will fire right back up as it did in the fall when you left it and forgot to plug in the battery tender. (Lead Acid need a trickle charge for long storage.) Lithiums real Achilles heal is cold temp. Charging it below freezing plates metal onto the plates, permanently destroying them by reduceing capacity. This makes me REAL nervous even riding it sub-zero. Just the bike running will top off the charge from starting it. That's a no-no. There are a couple expensive Li brands that have built in BMS (Battery Monitoring System) and even include pack heaters. Any 'charging' current when cold really goes to the heater. I have not tested any motorcycle batteries at work so can't say how much better one brand is over another or those w/ heater systems actually work.

The PO put a Shorai in the 500 and it's worked great. The 150 has whatever Li KTM installed factory and either the battery is already weak or the starter is weak. I need to jumpstart w/ a car and see which it is (though I'm betting its the battery.) The Duc has killed at least two lead acid batteries since I've owned it. I either forget to plug in the tender over winter or the darn gfi outlet in the garage trips and I don't notice until spring. I don't ride that in the cold really so it'll get a Li batt next time it happens.

When I do get a Li batt, I'll probably get a cheap one from Rocky Mountain or Amazon and do some cycle testing at work on it. Almost all of them come from the same Chinese factories and are likely brand labeled anyway. Will let everyone know what I find when it happens.

Re: BRP battery

Posted: Wed Jan 15, 2020 9:15 pm
by Bucho
I replaced all the batteries in my bikes with Li type. Im happier.

Re: BRP battery

Posted: Wed Jan 15, 2020 9:16 pm
by Laoch
Thanks. I'll jump it to see if it spins faster. If it still spins slow. Starter?
I hadn't considered the starter.

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Re: BRP battery

Posted: Wed Jan 15, 2020 10:22 pm
by J&J
For what it’s worth my BRP has a big bore & cranks a little slow for an instant then fires right up with a relatively new cheap Walmart battery. Walmart is close, the batterys are in stock & I can buy another one when it dies. The bike has always cranked like that, Jacob’s too. I do try to keep a battery tender on them.

Re: BRP battery

Posted: Thu Jan 16, 2020 6:58 am
by Laoch
Good to know. I've been getting my batteries from Batteries Plus.
I think it a Duracel Ultra. Probably same as every other battery I guess.

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Re: BRP battery

Posted: Thu Jan 16, 2020 10:02 am
by juddspaintballs
I'd investigate the battery cables, too.

Re: BRP battery

Posted: Thu Jan 16, 2020 10:07 am
by juddspaintballs
Also, a quality Li-Ion motorcycle battery is Antigravity. I believe they are made on US soil. The company stands behind their product and they are priced similarly to Shorai batteries. The one in my dirt bike even has "restart" technology where if you discharge it completely, there's essentially a second battery in it and by the push of a button on the battery, you have your own jump pack built in.



https://antigravitybatteries.com/produc ... m/atz7-rs/