Have maybe 10hrs on it and it just started making a knocking sound at idle and just above. It's not the normal ticking sound from the valvetrain. I have read that after boring to a 366 that the bottom of the jug can split or crack, is this true? I'm gunna guess it's either that or possibly the crank. What do these engines sound like when the crank takes a crap? Are these engines bad to split the cases on? I have done it on a kfx400 and it wasn't that bad.
Started making a knocking sound on my 366 yarrior
- Thread starter mvvette97
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97warrior_rider
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If u can split the case on a kfx400 the warrior is going to be just another walk in the park for ya bro if you hear a clacking noise it is possible it's the crank but I would get some more opinions from some of the yfms finest lol they can give you a lot more input as to what is going on before you start tearing it Down again might be a simple fix
88WarriorBoy
Well-Known Member
What octane fuel are you running and what compression ratio is that piston
'00 WO-YA!
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that's what I want to know.
88WarriorBoy
Well-Known Member
I'm thinking Pre-detonation
I'm running the 10.5 to 1 JE piston for the 4mm over bore. It was fine and just started doing this. I ended up pulling the topend off and it seems the rod is bad. I have the engine out now. The rod doesn't really have much if any up and down play but it spins rough on the crank. So it looks like a new crank is in my future. Now just a thought is there a stroker crank that I can use with my JE piston? If I have to buy a special piston I will go back with the stock stroke crank. I spent alot of money for that damn JE piston so I want to use it. Oh and is there a thread on here that shows how to split the cases? I have it about ready to split but just want to know what to look out for. On my kfx all the tranny gears stay in the flywheel side case, is the warrior the same?
duneracerweston
Well-Known Member
Warrior trans stays in the clutch side case.
You will need a flywheel puller.
Otherwise its really simple.that 400KFX motor is much more of a pain then these 350s are.
Just take your time and don't loose bolts. Thats about all there is to it.
To run a 85mm je (2mm over bore or .080 or a 366 which ever you choose to call it) requires a spacer plate to get your deck into spec. Talk to these guys and they can help with that. Crank cost is higher for the stroker, along with cooling issues become prevalent with a 388 motor. (+4mm stroke, 85 mm piston) but those can be solved with air ducts header wrap or ceramic coating, and oil cooling.
The build is up to you, cost is higher on the stroker and wont be as snappy but high gearing is less of a strain with the stroker.
All that being said, I am quite happy with my 348cc build motor.
You will need a flywheel puller.
Otherwise its really simple.that 400KFX motor is much more of a pain then these 350s are.
Just take your time and don't loose bolts. Thats about all there is to it.
To run a 85mm je (2mm over bore or .080 or a 366 which ever you choose to call it) requires a spacer plate to get your deck into spec. Talk to these guys and they can help with that. Crank cost is higher for the stroker, along with cooling issues become prevalent with a 388 motor. (+4mm stroke, 85 mm piston) but those can be solved with air ducts header wrap or ceramic coating, and oil cooling.
The build is up to you, cost is higher on the stroker and wont be as snappy but high gearing is less of a strain with the stroker.
All that being said, I am quite happy with my 348cc build motor.
'00 WO-YA!
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^ Yup, I have no complaints with my 366. I would consider a +4 crank with the CWR big bore though.
I decided to just go with the stock stroke hotrods crank. i have a service manual that I forgot I had and it says and shows all the tranny stays in the flywheel side of the case. it says to lay the engine on the left side and pull the right side case up. So what way is the best?
YAMAHAULER
Well-Known Member
That's wrong the trans gears stay in the clutch side(right side) I just did 2 in the last 4 months
YAMAHAULER
Well-Known Member
should come with new bearings and the sprocket
Sure hope so. I tried getting that sprocket off and that thing is on there for life. Oh and I will say it was much more easy splitting the case on the warrior than my kfx. I will be doing it again very soon also. Have a stroker on the way for the kfx.
YAMAHAULER
Well-Known Member
if you want to be sure on the bearings and sprocket just email them and they will be able to tell you for sure bro
I sent them an email sp I guess I will see what they say. I done some web searching and it does look like it should come with a new gear and bearing but not for sure
