Posts
16
Joined
2/1/2026
Location
Dartmouth, MA
US
Bought a leftover 25 yz 450. Pulled suspension off for respring. Its been sitting month ish with 2' of snow in the ground. Put it back together. Start Buttons completely dead. Going to test battery tonight. But wasn't sure if there's some sleep mode or something on these. Or just dead battery from dealer. Any ideas? Thanks
Never heard of a sleep mode.
Seems like your battery is dead or the terminal cables aren't connected.
The batteries that come with the new YZF’s do have a protection feature which allows them to appear as if they’re “dead” - it kicks in if they drop below a certain voltage. All you need to do is connect another battery of similar size to “jump start” your bikes battery (it literally only has to be connected for 3-5 seconds). If you have a multimeter, connect that to your bikes battery when jump starting it to see if it does come back to life.
Yah on a meter its at 0v DC. Not even a low voltage where my austrian bikes stay at 13v. Hooked up lithium charger and charger not even reading anything to start trickling. Weird scenario. Need to hit it with a battery like you mentioned.
Curious to know if a new/ charged battery fixed your issue. If it didn't, check ground at the frame for good contact and connection.
The Shop
Luxon 4-Post Bar Mounts
$189.95 - $239.95
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This may help - similar thing happened to me:
https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/A-brand-new-2020-…
Post a reply to: 2025 brand new yz 450 no start