Looking for some opinions/advice on what route to go about here.
Went out to sleepy hollow Mx (PA) and got sone good riding in. End of the day I look and see there’s hardly any oil in the glass and oil all around the oil filter/oil fill area under the water pump. The bike was still running fine during the last session. I’m hoping that it’s an o ring on the filter cap or needs a new drain bolt or something simple. I’ve attached a picture of where I think there might be a hairline crack. Im going to clean the bike and do all the normal after ride maintenance then turn the bike on and see exactly where it’s leaking from.
now if it is a crack and not a casting mark in that picture then any ideas on how to go about it. I’d have to check my app but the damn bikes got less than 12 hours on it. Would it be worth talking to Yamaha or just try the ol jb weld method. 
Looks like a crack to me. Clean the bike and drop the oil too see how much oil you lost. Getting a cracked side case warrantied might be an up hill battle but worth a try. My fear is losing that much oil may have starved the cam journals. I would clean it and take it to the dealer to see if they are willing to diagnose and talk to Yamaha. Good luck and keep us posted.
I thought I hada cracked case on my YZ250 and Yamaha made it like pulling teeth but they were willing to make it right. It didn't end up being that, just a freak scenario. Point is, they were willing.
It could be a crack but it doesn’t look like it to me. The o-ring on the oil filter cover could have a place where it caught or a piece of sand could be wedged. That happened to me once. Looks like the oil is to high up to just be splatter from that crack.
I’ll bet it’s fine and a casting mark. Check that o-ring and get back to us
Sometimes it's possible to mess up an oil change and not out enough back in. Just work through the trouble shooting and keep an eye on your oil. Some good suggestions here, it's amazing how many years on forums so many casting flaws and not many cracks hahaah
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If it is a crack, a competent welder can fix it easy.
Yamaha holds 30 day warranty, but they sometimes do goodwill.
call the shop!
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