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looking into rebuilding head

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Old 03-16-2008, 04:40 PM
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Default looking into rebuilding head

i have a 87 warrior 350 and i was thing about rebuilding the head. i had ordered valve seals and decided to just do a rebuild. can i just order new valves and use the springs and guides already in there, or should i order everything but the cam?

i also would like to buy a new piston and rings, i'm assuming i have a wiseco piston in there now but i'm not sure. (there's a wiseco decal on the plastic that's what makes me think there's a wiseco piston in it). also how do i know what size piston to get? will the piston have the bore size on the top of it, or is that just a part number? i had it out once before and remember seeing numbers on the top of it, but not sure if it's the size or part number.

one last question, when ordering the stuff for the head, should i go aftermarket or stock?
 
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Old 03-16-2008, 11:11 PM
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Default looking into rebuilding head

Depends on what you are doing with the quad. If you are keeping it mostly stock (save a pipe or air filter) then OEM parts are fine. When buying pistons they list the piston for your bike. Stickers mean nothing, by the way. My quad is all decked out in parts and I didn't put any of those ugly *** stickers on there, and some guys will just put any sticker on they can get their hands on. If you are going to replace the piston you would be much better off to do a small bore job on it and go to a .020 or .040 over, so it will have fresh cylinder walls to seat against and keep good compression.
 
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Old 03-16-2008, 11:34 PM
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Default looking into rebuilding head

If I were you I would just replace the valve seals and guides. Inspect the valves and springs and make sure they are within spec.

You should be able to get the size of the piston off of it, or just measure it and that will tell you what it is. It will be in mm's. Stock parts for the head will be fine.
 
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Old 03-17-2008, 12:47 AM
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Default looking into rebuilding head

the whole bike is stock except for pipe and air filter. i'm not really looking for much performance. all i do is trail ride and ride in the pit. i already ordered the valve seals, i will order the guides as well. also i looked up the piston size and it's 50mm which is stock. but that doesn't really help because i don't know what's in it now..... now, if the piston is fine than i can just order new rings right?
 
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Old 03-17-2008, 12:21 PM
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Default looking into rebuilding head

yes you can order new rings, but 50mm isn't stock on a warrior 83mm is fyi.
 
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Old 03-17-2008, 03:36 PM
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ok, thanx for the correction pmc. when ordering rings is there a certian size or are they all the same?
 
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Old 03-17-2008, 03:43 PM
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Default looking into rebuilding head

they r diffrent sizes depending on the bore. you will need to find out if the cylander needs to be bored before you order a piston and rings, then order them and whoever does your bore job will match it to the rings unless its fine then you will just order a standard ring for the warrior, but biegn a 87 I bet you will have to be bored.
 
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Old 03-17-2008, 08:33 PM
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i bored cylinders before so i can do that myself. but i don't have the bore measurement tool. is there a way to find out what the bore size is with out it? and if it does need to be bored how mm's should i go?
 
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Old 03-17-2008, 10:34 PM
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Did you actually bore a cylinder, or just hone one out? There is a big difference. Unless you have a machine shop, I would guess you just honed a cylinder?
 
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Old 03-18-2008, 12:09 AM
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yea sorry that's what i meant. i honed a cylinders before in my 88 camaro. but i never did it on a quad.
 


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