warrior doesnt wanna start??

[Gen1Pat]

I checked both of mine earlier just for the hell of it. Its funny, the Warrior with a fresh set of rings and an Arias 10.25:1 piston shows 165PSI cold with throttle wide open. The Raptor 350 that supposedly has never been apart and has some hours on it comes up at 160PSI cold with throttle wide open.

When I picked up the engine that is in my bike now (original has bad rod bearing) I did a comp test after I got it in the chassis. Had 155psi cold without carb installed. And that engine sat for (most likely) close to a year before I got it. Never tested it after I rebuilt though.

 

[MidwayUSA]

When I picked up the engine that is in my bike now (original has bad rod bearing) I did a comp test after I got it in the chassis. Had 155psi cold without carb installed. And that engine sat for (most likely) close to a year before I got it. Never tested it after I rebuilt though.

I figured the Arias piston would create more cranking compression. I think the cam profiles on the Raptor 350 are a little different and I suppose that is why they are similar. The higher compression sure made the noisy starter clutch a lot worse. I bet it goes out next on me.

As for you dillonj you still aren't willing to admit defeat?? THE EFFING VALVES ARE BENT THIS TIME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

[dillon14dj]

I figured the Arias piston would create more cranking compression. I think the cam profiles on the Raptor 350 are a little different and I suppose that is why they are similar. The higher compression sure made the noisy starter clutch a lot worse. I bet it goes out next on me.

As for you dillonj you still aren't willing to admit defeat?? THE EFFING VALVES ARE BENT THIS TIME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

i never said that. i just would rather not think it as they are like $200? and im not made of money.. the more i spend on this the longer it takes me to make more money (as im in the trade market of buying and selling things). and i was just offer a nice 600cc honda dirt bike for this but the guy is seeing if he can fine a truck to get down here

anyways tho. im getting to the valves (as it would be nice to know the problem for sure). i just made a video of them (not sure if it will help any tho?). about to make another thread and up it

 

[MidwayUSA]

i never said that. i just would rather not think it as they are like $200? and im not made of money.. the more i spend on this the longer it takes me to make more money (as im in the trade market of buying and selling things). and i was just offer a nice 600cc honda dirt bike for this but the guy is seeing if he can fine a truck to get down here

anyways tho. im getting to the valves (as it would be nice to know the problem for sure). i just made a video of them (not sure if it will help any tho?). about to make another thread and up it

You should be able to get a stock pair of valves for less than $100. The last exhaust I bought new was an aftermarket valve and it was around $27. I doubt you will, but you should at least lap the valves in. Probably would be better to have the seats cut or ground. That is another expense and God forbid we do it right so it won't cost more money!!

 

[Gen1Pat]

opcorn:

 

[MidwayUSA]

:haha:

opcorn:

 

[Gen1Pat]

I figured the Arias piston would create more cranking compression. I think the cam profiles on the Raptor 350 are a little different and I suppose that is why they are similar. The higher compression sure made the noisy starter clutch a lot worse. I bet it goes out next on me.

You would think that with the higher comp piston. Mine made the 155 with a (found out when I tore it down) .020 yamaha piston. So it was rebuilt once before, and I'd guess not TOO long ago.

 

['00 WO-YA!]

opcorn:

X2, lol!

Aight guy, everyone keeps telling you to check compression b/c it will get you to the bottom of things. If the valve is bent then the engine can't make compression (it leaks by the bent valve). I keep reading posts about turning screws & adjusting this & that. It's all snowballing on you man, don't **** with the carb until ya check compression. Sadly in an earlier post you were making reference to the valve lash adjustments as if you had no idea what they even were or where they are adjusted at. Do you know? Serious question, do you know what the valves are lashed at or how to properly adjust them?
I just see this continuing down a path to nowhere, sorry, I encourage people doing their own work but just let someone that knows how to fix it..fix it.

 

[MidwayUSA]

I figured the Arias piston would create more cranking compression. I think the cam profiles on the Raptor 350 are a little different and I suppose that is why they are similar. The higher compression sure made the noisy starter clutch a lot worse. I bet it goes out next on me.

You would think that with the higher comp piston. Mine made the 155 with a (found out when I tore it down) .020 yamaha piston. So it was rebuilt once before, and I'd guess not TOO long ago.

Sad thing is, I work in a machine shop and I don't know the answer on the compression thing. I know that static compression and cranking pressure are somewhat related, but I also know that duration on the cam can affect cranking pressure too. All I know is I need race gas or race gas/91 octane mix now. This thing was pinging a little yesterday under load. That was with 91 octane and Blendzall. I sure would have thought that would have been enough, but it was also 90 some odd degrees out too.

dillonj, with a bent valve depending on how bad, you will have either low cranking pressure or none at all.

 

[Gen1Pat]

Also, a bent valve may not be easy to spot from looking in throught he rocker covers. You may have to remove the head to get an accurate asessment of the damage. It could have slapped the piston just enough to cause it not to seat fully against it's valve seat, and compression is being lost(much like having a burnt valve).

 

[dillon14dj]

Also, a bent valve may not be easy to spot from looking in throught he rocker covers. You may have to remove the head to get an accurate asessment of the damage. It could have slapped the piston just enough to cause it not to seat fully against it's valve seat, and compression is being lost(much like having a burnt valve).

so its just gonna be more easy if i just take the top back off? (i wouldnt have to replace the gasket again would i?) and i know the gasket set i bought came with other things also (what i have not used) like the valve seals.

but what i am more worry about is i dont wanna strip the head bolts by undoing them so many times.

if i dont have to replace the gasket again. even tho its 30 outside (proly hotter in my shed) ill go out and take the head back off again right now

 

[Gen1Pat]

You have a bent valve or valves so the head has to come off anyway. Your timing is correct so the only thing left is a bent valve(s). Just like what was said in another thread of yours, there is move play in the exhuast rocker because the valve is most likely bent and not closing all the way. Can you reuse the hed gasket... yes it has been done, but I always use new. As for the head bolts, they shouldn't strip, unless you cross threaded them in. Many of the bike on here have had their engines rebuilt countless times and have had narry an issue. Some of use have had to put heli-coils in when they do strip. Just be carefull and you should be fine.

 

[dillon14dj]

You have a bent valve or valves so the head has to come off anyway. Your timing is correct so the only thing left is a bent valve(s). Just like what was said in another thread of yours, there is move play in the exhuast rocker because the valve is most likely bent and not closing all the way. Can you reuse the hed gasket... yes it has been done, but I always use new. As for the head bolts, they shouldn't strip, unless you cross threaded them in. Many of the bike on here have had their engines rebuilt countless times and have had narry an issue. Some of use have had to put heli-coils in when they do strip. Just be carefull and you should be fine.

just took the head off. heres some pics.. pretty sure the exhaust valve had a tan colour before?

 

[Gen1Pat]

Is the cam gear mark lined up with the notch? If so your exhaust valve is deffinetly bent, you can see that it is not seating fully against the head.

 

[dillon14dj]

Is the cam gear mark lined up with the notch? If so your exhaust valve is deffinetly bent, you can see that it is not seating fully against the head.

when the head,/camgear and chain isnt on the camshaft. you can move the camshaft freely a lil bit. i just went in the basement and moved the camshaft to the mark and it doesnt move the valve.?

what is my next step on this people?

 

[MidwayUSA]

Make sure the mark on the cam gear is pointing up. Pour some solvent or some liquid in each runner and see if it freely runs past the valve and seat. If so it is bent.

 

[dillon14dj]

Make sure the mark on the cam gear is pointing up. Pour some solvent or some liquid in each runner and see if it freely runs past the valve and seat. If so it is bent.

would use oil work? and i know this may sound dumb but what do you mean by that? pour it in at the top and see if it comes out the bottom thru the valve?

also am i gonna need to order this? http://www.ebay.ca/itm/Yamaha-Warri...ccessories&hash=item1c1f57df58#ht_1156wt_1037

 

[dillon14dj]

i believe i can skip that step^??, i just put it upto the light and i can see right thru it so its bent!

how do i take it out? to replace it.. also is that $23 exhaust valve ^ ok. or do i need a Wiseco Exhaust Valve?

 

[Gen1Pat]

Do it this way... Make sure the cam gear is pointing at the notch in the head. Turn the head upside down and stablize it with blocks of wood (or whatever you have). Then, pour some solvent, or the used oil ON top on the valves. After you have done that, look into the holes where the carb and the exhaust bolt to. If the fluid you poured onto the valves is in there then one or both of the valves are not sealing correctly and need replacing. In the one pic you posted the exhaust valve doesn't appear to be seating. Looked like there was some space between it and the valve seat.

 

[Gen1Pat]

You need a special tool to compress the valve spring, to remove the lock and retainers, then with them out of the way, the spring comes out, then the valve, etc... And you HAVE to have the tool.