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On the TRX350/350D motors the top sprocket bolt hole has a mark above it on the outboard side. Those two mounting bolts will be vertical when both timing marks are horizontal (timing marks even with the top of the head, both cam lobes facing down, piston @TDC). The top bolt hole in the sprocket is also drilled smaller in diameter than the bottom hole is.

On the 14321-428-000 sprocket (which interchanges with the original 14321-HA0-010 sprocket) the top bolt hole is not marked, but that top hole is drilled smaller than the bottom hole is.

You can put those sprockets on the cam upside down if you wish (since both mounting bolts fit inside the smaller drilled hole & all markings are perpendicular to one another) with no ill effects.
 

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Replaced head on 350 timing is correct fuel is shooting out the back of the carb
In your case, one or both of the following statements are true:
a) The camshaft chain and sprocket are installed out of time.
b) The valve lash was not adjusted properly after installing the head cover.

After you correct your issue check the operation of the compression release.

Keep us posted if you can...
 

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Discussion Starter · #7 ·
Replaced head on 350 timing is correct fuel is shooting out the back of the carb
In your case, one or both of the following statements are true:
a) The camshaft chain and sprocket are installed out of time.
b) The valve lash was not adjusted properly after installing the head cover.

After you correct your issue check the operation of the compression release.

Keep us posted if you can...
It is an 89. My timing is perfect and I have the valve lash at .005
 

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You replaced the head, so the only other reasons left for that is a stuck, burnt or bent valve then. Assuming the cam timing is correct and valve lash is not too tight... both valves should be adjusted to .003" stone cold. These should be quick and easy to verify.
 

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Cam lobes are definitely facing down when piston is at TDC, yes?
 

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Bent valves are caused by one of two things:
The cam chain jumping over the sprocket teeth on a running motor, due to excessive chain wear, thus causing the piston to contact open valve(s).

OR

The camshaft being installed out of time with the crankshaft and the motor then forcefully cranked over by the electric starter or kickstarter, before the installer verified the assembly by rotating the motor two revolutions by hand.

Those valves are probably discontinued... but Shindy (and possibly Vesrah?) still supply them for roughly $50-$75 per set of four. 86-89 (thru 93 in Canada) 350s all use the same valve sets. You may need to buy valve springs as well... they become sacked with age. New valve seals certainly, and check the valve guides for damage caused by bent valve stems or excessive wear.

Keep us updated... and have fun!
 

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Discussion Starter · #15 ·
I didn鈥檛 send to him he sent to me. And duck I used the ones from yours cause of the whole same valves seating right thing. I鈥檓 gonna try to use the ones from my old head and rent the tool from oreilies to redo the seats and such if my boss doesn鈥檛 have the tool. If the won鈥檛 seat right I鈥檒l just get new valves
 

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Retro, you're not butting in at all. We'd probably all benefit more from your insight. I 've never done any top end work before, other than setting valve clearances. I was asking about which valves because I would have thought the ones I sent were good versus his out of a head that had major camshaft damage.

In any case, I'd be concerned about the valve guides now too. I'd imagine running with bent valves can't be good for them.

I'll be doing one of my top ends this week for the first time. I ordered new exhausts gaskets for the head along with new studs and nuts. You may want to consider new exhaust gaskets too, Stever.
 
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