Engine talk. Rebuild, and cam.

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jasonp

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Well yesterday I decided to take the old warrior out for it's last beating before rebuilding the engine and try a new custom cam that Web is coming up with for me. That and I wanted to take the old beast for a ride as the raptor 700 was getting most of the love.. (fat girls need love to right) jk

Before I took it out I only had 175 psi cranking compression, where at the begining of the summer had 225 psi.

Engine noise was getting pretty loud when shutting her down. Big clunk noise. Sounds like a rod bearing or piston hitting the valves.

Engine feels flat, doesn't have the power it did before.

So I have started the process of taking the engine down. I've forgotten how easy this little thing is to work on. I've used no special tools except for pulling the flywheel.

Kind of interesting. I checked my deck height when taking the engine down. .001" and head gasket of .032" Piston only had around .035" of clearance or so, this is with a stock cometic base gasket of .020". Looks like it crushed to around .015" or so. JE looks to have deck corrected pistons which I previously thought this wasn't the case. Looks like my .005" cooper gasket isn't going to work like had thought. I was hoping to be able to pick up a little compression by lower the jug (cylinder) down.. but I'm already at .001". Looks like 225 psi is about the limit on a 10.5:1 85mm JE piston. I was hoping to up that more and see how much I could run on pump gas. Damn it.

BTW: clearance from piston to head should be around .035 to .040" any less you risk of the piston and valves or head making friends.

I could have a custom piston done by JE or CP??...

Bore looks completely worn out, no cross hatch left. So it will be interesting to see what duncan says if it needs a new sleeve or not.
(engine has got around 5000 miles on it since last rebuild) Looks like this is where I am loosing compression.

Head has already been gone through by duncan before but I think I'll send it back to them and have them put in this KW black diamond exhaust valve as well as have it freshed up. As some of you know it was ported and had a 5 angle valve job done with a 1mm valve it in by duncan previously.

The .450" lift Megacycle cam is for sale, it's a billet one. I'm switching to a custom web cam from them.. It's going to have a lot of lift like this cam but shorter duration...


Let me know what you guys think. If wanted I can post some pictures of the work.


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I was going to get rid of the Dynatek as well and go back to my vito's timing key. I really like the limiter and being able to adjust timing. With this cdi though it tends to cut off spark when coasting or say if you get off the throttle quickly it will cut spark.. It's kind of anoying.
 
I can imagine, I have a new .450 Megacycle that I'm looking forward to trying. Initially I wanted to try a 12:1 JE 85mm but I'm gonna give a Weisco a shot with a freshen up. I Will eventually do a 366 or maybe even bigger, I think I'd like to try one of the CWR 400 OR 460 kits. We'll see, one day at a time. I'm going to take some measurements with the Weisco & see if I can get by with lowering the jug like you mentioned. I'm a lil concerned with p to v clearance with all of the lift that the .450 has. Again, we'll see.
 
That's sucks man. When was the last time u had er out? I should be a fun rebuild. The he deck info is quite interesting, and I'll have to keep that in mind when I get my head back. If. U switching to the vitos key, do you have a adj. cam gear yet? I'm interested to see how your project pans out. I good luck.

Any ideas yet on what type of numbers you want to make your cam have?
 
That's sucks man. When was the last time u had er out? I should be a fun rebuild. The he deck info is quite interesting, and I'll have to keep that in mind when I get my head back. If. U switching to the vitos key, do you have a adj. cam gear yet? I'm interested to see how your project pans out. I good luck.

Any ideas yet on what type of numbers you want to make your cam have?


I basically ran it all summer. Got the raptor 700 late oct.

Yep, I have to keep the adjustable cam gear as it helps me get the cam in time.

The cam I believe (I haven't seen the numbers yet) will be close to what you got in spec's but more lift.

Thanks!
 
Man thats a worn cylinder. Try cp ive heard of people actually preferring them more but see which one gives the better price.


Yeah it's about what it looked like the last time I rebuilt it. I think there was another place that did a piston. shaker pistons??
 
hmm with those marks in the jug i got 5 bucks on a new sleeve!

that piston looks relatively clean did it smoke any?

ans you should change to the Ti valves if your looking for more comp the ss vlaves are dished out the Ti valves are not. if you didnt already know that.
 
hmm with those marks in the jug i got 5 bucks on a new sleeve!

that piston looks relatively clean did it smoke any?

ans you should change to the Ti valves if your looking for more comp the ss vlaves are dished out the Ti valves are not. if you didnt already know that.


Go big or go ******* home is how that works.

Jetting was pretty close to spot on. Also helps when you run little deck clearance.

Didn't smoke at all. Didn't burn any oil.

I will just have more shaved off the head. Actually I've seen ti valves that are dished out.
 
KW? ive neve seen warrior Ti valves that were dished but thats just me

mine has .041 deck on it will it burn that clean?

KW only sells SS valves for the warrior. Are you speaking generally or what for the warrior head and ti valves.. post up a link.

Not if your jetting is off, which it sounds like.

How much deck do you have with no base gasket and your wiseco piston? How far was the piston down below the top of the jug?
 
piston-jug height .002
piston to deck .041
piston to valves was way more then the .070 i used to test for

mine was burning alot of oil when i tire it down so thats probably were the carbon on mine came from

i have never found Ti warrior valve via the web but the man that did the head work on mine (Mr. Gerald Jessup) said that KW makes them at least thats what his book says and that the TI valve for the warrior head (especially the Exh) were not dished. my exhaust valve has about a 2-3cc dish compared to the stock valve.
 
piston-jug height .002
piston to deck .041
piston to valves was way more then the .070 i used to test for

mine was burning alot of oil when i tire it down so thats probably were the carbon on mine came from

i have never found Ti warrior valve via the web but the man that did the head work on mine (Mr. Gerald Jessup) said that KW makes them at least thats what his book says and that the TI valve for the warrior head (especially the Exh) were not dished. my exhaust valve has about a 2-3cc dish compared to the stock valve.

Interesting that the wiseco sits that much lower down in the cylinder bore, at least .020" more then the JE. You would think being the compression is pretty close to the JE it wouldn't be that much different. Must not be deck corrected piston.

Yeah with my .390 cam I was is spec for piston to valve clearance. The .450" is much tighter.
KW does make them for other bikes. Just not the warrior. I suppose you can get them custom made. I found that both KW valves seem to be more dished then stock.

Got any pic's of your head? What head gasket do you run?
 
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Interesting that the wiseco sits that much lower down in the cylinder bore, at least .020" more then the JE. You would think being the compression is pretty close to the JE it wouldn't be that much different. Must not be deck corrected piston.

Yeah with my .390 cam I was is spec for piston to valve clearance. The .450" is much tighter.
KW does make them for other bikes. Just not the warrior. I suppose you can get them custom made. I found that both KW valves seem to be more dished then stock.

Got any pic's of your head?

not after head work i am always to anxious to get it going again i forget to take pictures. lol

maybe its just me but that je looks like a smaller dome then the wiseco. i bet with deck correction they need less dome and still get better comp.
 
not after head work i am always to anxious to get it going again i forget to take pictures. lol

maybe its just me but that je looks like a smaller dome then the wiseco. i bet with deck correction they need less dome and still get better comp.


Do you know the dome height of yours. The JE is .100". Which from what I've read is the most you want to go other wise you will effect combustion chamber dynamics. The wiseco might be shorter and larger around raised pad? I be worried your piston pad would hit the quench area of the head because it is not shaped like the combustion chamber.

What head gasket you running?

Yeah when I first rebuilt mine I just wanted to get it together and run it.
 
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