Thanks for vid, good to know. I have same bike, same year almost 140 hours no faults so far. Love the bike. Need to replace factory battery for stronger one though.
I had the exact same problem on a 2016 300. It's not an install issue, it's a design problem with the gasket slowly pushing out over time. Happened twice, until I put a thin coat of rtv on the new gasket before putting it back together. Hasn't moved since.
This problem is common on the Yamaha 2t Jetski engines for decades. The oem gasket has a rubber coating in a thin area of the gasket and on paper aftermarket gaskets it is normal to put a thin coating of good gasket material on the thin area of the base gasket. I have a Sherco 300 2t also so thanks for the tip.
Having the same problem with the power valve, top end it just dead and flat. Ran the bike with the actuator off and it didn’t look like it was opening all the way so I cleaned all the plugs (one you said was absolutely full of shit). Now looks like it’s opening fully and working smoother. Haven’t ridden it yet but this has made me hopeful that it’s sorted
Are you sure the sprocket is not runing true. It could be the mold shifted and the center is off. But after they do the machining process everything is true, but the inside of the casting is off a bit...
That piston looks pretty good for 150hrs in all fairness, you probably would of got 50+ more if that gasket wasn't buggered. Just shows how great modern 2st are, especially after doing Weston.. which we all know can kill a bike pretty quick if its got the slightest of weaknesses. 😎👍
I have a 300 sef that has just blown the base gasket The bike has only done 48hrs I’m waiting to hear what may have caused the problem The bike was running fine until I noticed oil leaking from the gasket
Gasket is likely blown forward by a backfire event in the crankcase. It happens sometimes 🤷 Cylinder head nuts soft... 🤔 They're normal every day nuts, easy to undo with the right size tools, I've undone numerous bikes now and not damaged any. All the best.
All the people I know that have owned one of these bikes have had a plethora of issues.... Many different problems like coils popping, starter motor getting some kind of a shim stuck into them that leaves them stranded because there's no option at all for a Kickstart, frames cracking, power valve cables snapping... Now, your gasket problem.... I can't believe the sprocket not centralised! That can cause endless hassles with your gearbox... 🙈🙈...! No wonder they're referring to them as Shitco...
Thanks for vid, good to know. I have same bike, same year almost 140 hours no faults so far. Love the bike. Need to replace factory battery for stronger one though.
thanks for the tip, I had a small coolant leak in the front area, figured the base gasket is shot, now i'm sure of it.
I had the exact same problem on a 2016 300. It's not an install issue, it's a design problem with the gasket slowly pushing out over time. Happened twice, until I put a thin coat of rtv on the new gasket before putting it back together. Hasn't moved since.
This problem is common on the Yamaha 2t Jetski engines for decades. The oem gasket has a rubber coating in a thin area of the gasket and on paper aftermarket gaskets it is normal to put a thin coating of good gasket material on the thin area of the base gasket. I have a Sherco 300 2t also so thanks for the tip.
Hei. Sorry, whats is coat of RTV?
Having the same problem with the power valve, top end it just dead and flat.
Ran the bike with the actuator off and it didn’t look like it was opening all the way so I cleaned all the plugs (one you said was absolutely full of shit). Now looks like it’s opening fully and working smoother. Haven’t ridden it yet but this has made me hopeful that it’s sorted
Are you sure the sprocket is not runing true. It could be the mold shifted and the center is off. But after they do the machining process everything is true, but the inside of the casting is off a bit...
That piston looks pretty good for 150hrs in all fairness, you probably would of got 50+ more if that gasket wasn't buggered. Just shows how great modern 2st are, especially after doing Weston.. which we all know can kill a bike pretty quick if its got the slightest of weaknesses. 😎👍
Yes I'm very surprised how far 2 strokes have come over the years. Good maintenance and services they should last double the factory rebuild times.
I have a 300 sef that has just blown the base gasket
The bike has only done 48hrs
I’m waiting to hear what may have caused the problem
The bike was running fine until I noticed oil leaking from the gasket
150 hours on one piston, fuck that I change mine every 60 hours for the cost it’s bugger all. Nice job regardless 👍
Each to their own mate. She's got 220 hours now so defo time to change 🙈
How many hours have you been riding the bike ? Does the motor break down? Do you recommend this motor?
What head light is thst and were do you get one from
Great tip
Gasket is likely blown forward by a backfire event in the crankcase.
It happens sometimes 🤷
Cylinder head nuts soft... 🤔
They're normal every day nuts, easy to undo with the right size tools, I've undone numerous bikes now and not damaged any.
All the best.
All the people I know that have owned one of these bikes have had a plethora of issues.... Many different problems like coils popping, starter motor getting some kind of a shim stuck into them that leaves them stranded because there's no option at all for a Kickstart, frames cracking, power valve cables snapping... Now, your gasket problem.... I can't believe the sprocket not centralised! That can cause endless hassles with your gearbox... 🙈🙈...! No wonder they're referring to them as Shitco...
Bull Shit