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Discussion Starter · #1 ·
I've got a service manual for a K0, but I was unsure if the procedure was exactly the same or not. Thanks a bunch.
 

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Sensei
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Yep, except the covers don't have the K0 plus and minus marks........ You have to have the little indexes (yes, I know it's indicies) pointing away from the spark plugs........
 

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Discussion Starter · #3 ·
Forgive my ignorance, I feel like I get the gist of how this works as I've done it on my SOHC4s several times. Part of my problem is that I cannot get the timing marks to line up and then take my hand off the wrench on the crank because the engine wants to roll over if I'm not keeping it in place. Beyond that, do the aluminum covers around the adjusters need to come off to reveal something underneath that I need to be inspecting? Also, on the SOHC4s I can tell what valve is the one needing adjusting just by wiggling it, does the 450 work the same? Lastly, once I set one valve, how far will I need to rotate the engine, and which valve will I do next? Thanks a bunch.
 

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zoo mob said:
...Part of my problem is that I cannot get the timing marks to line up and then take my hand off the wrench on the crank because the engine wants to roll over if I'm not keeping it in place...
Once the timing marks gets close, use a crescent wrench on the the rotor bolt to slowly turn the crankshaft counter-clockwise. The crescent wrench can be adjusted so it holds the bolt with no slop making it easier to keep the engine from running past the mark. You have to keep one hand on the wrench (or two) and slowly approach the timing mark watching for the light bulb to light. You are using a 12V bulb aren't you?

zoo mob said:
...do the aluminum covers around the adjusters need to come off to reveal something underneath that I need to be inspecting?...
No...the covers are holding the cams.

zoo mob said:
...on the SOHC4s I can tell what valve is the one needing adjusting just by wiggling it, does the 450 work the same?...
You wiggle the valve? Or the follower? You should be able to wiggle the followers, but that's not how to tell if they need adjustment. You need a feeler gauge between the cam lobe and the follower.

zoo mob said:
...once I set one valve, how far will I need to rotate the engine, and which valve will I do next? Thanks a bunch.
When the timing mark is on "LT" you can adjust the left intake and exhaust followers. When the timing mark is on "T" you can adjust the right intake and exhaust followers.

Hope I wrote that how I was thinking.
 

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Discussion Starter · #5 ·
Well, I'm feeling like a bit of a dipshit now. I didn't read the last reply correctly and tried to take the cover off around the adjuster. Boy, it was hard to get that thing off, and then I realized I was pulling the cam out. AWESOME! I pushed it back into place, is there anything I need to worry about?

I did thankfully manage to get the marks to line up without keeping my hand on the wrench, now I'm wondering how I know if its the exhaust or intake valve that needs adjusting? Sorry to seem so clueless, I'm slowly working my way through it. Any help is welcome.
 

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zoo mob said:
Boy, it was hard to get that thing off, and then I realized I was pulling the cam out. AWESOME! I pushed it back into place, is there anything I need to worry about?
Possible to bent a valve stem doing that, check your compression
 

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Discussion Starter · #7 ·
Well, its back together, and seemingly ok. Compression test showed about 120 on each cylinder. So from the top, could somebody walk me through this like I'm a five year old who speaks english as a second language? I get it in principle, but I'm still feeling lost.
 

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Sensei
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Bird is correct....... 163 PSI is the Minimum spec for the (DOHC) 450's, BUT, let's pretend that the engine was cold, the carbs weren't fully open, and your valves are currently mis-adjusted enough to account for that discrepancy......

Lets start with the left cylinder:

With spark plugs out, and turning crankshaft ONLY CCW (viewed from left side of bike as you sit on it), rotate the crank until the Left INTAKE valve closes.... Continue rotating CCW until the LT mark on the rotor just aligns with the index pointer, and HOLD it there...( LT should still be on the index during this whole process, so a friend to hold it there helps.....)

Adjust both LEFT cylinder tappets to .0012 INCHES, (with the feeler between the CAM lobe and the tappet, NOT at the valve to tappet junction).... (Most people just use a .002" feeler, although I use a .0015" )........
Once both left valves are adjusted and locked down, VERIFY that the small line on the adjuster shafts (90 degrees off the screwdriver slot) is on the side away from the spark plug hole.....This is CRITICAL, as there are actually two points on the excentric's rotation that can/will yield the correct setting, however, one will cause excessive cam to tappet pressures....(Cam and tappet damage).....

Once you are SURE the left side is correctly adjusted, locked down, and verified, continue to rotate the crank CCW until the right cylinder intake closes and then align the "T" mark on the pointer.......Hold it there and adjust both right cylinder valves following the same "rules" for clearance and verification.....

I hope this was "5-year old" enough for you...... :D :D Steve
 

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Discussion Starter · #10 ·
I think my only other question is how do you know when the intake vs. exhaust valves are closed? On my sohc 4s, I would just jiggle the follower (or whatever its called) to tell which needed adjusting. When I got the marks aligned and tried it on the 450, there was seemingly no play.
 

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Sensei
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Adjusting the valves is a waste of time until you re-ring......Again, 163 PSI is MINIMUM spec for a 450....It will run at 120 PSI, but it won't PULL well....
 

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Discussion Starter · #12 ·
Well, the bike is not getting new rings, it is getting sold. It was in fact cold, and the throttle was not open when I did the compression test. Any help here? I'm just looking to shut up the valve noise.
 

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Ok...Back to valve adjustment...(Just FYI, figure 15 to 20PSI for cold and closed)....


Left cylinder valves at LT on the compression stroke....Measure between the cam and tappet, not the tappet and valve..... .0015 to .002" is commonly used, but the actual spec is .0012" (very small), so it may appear as if there is no gap if you are using an oversize feeler..... Right cylinder at "T" on its compression stroke....
 

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Discussion Starter · #14 ·
I feel really stupid for making something so simple seem so hard. It was simple and the bike sounds way better. Now, on to dealing with jetting etc.
 
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