degreed cams now exhaust valve hits
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degreed cams now exhaust valve hits
Bike was running, degreed cams, now exhaust valve hits piston? Do these valves run that close to the piston that a few degrees can make them tag the pistons? The head has been cut but it ran 1500miles before I degreed the cams.Tags: None -
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sharpyComment
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To a high degree there appears to be a degree of agreement in this thread......
Sorry - you asked a sensible question and some of us couldn't refrain
. The valves do run close to the pistons but my guess is that you haven't set something up right. Check and double check your starting point - dead easy to mess it so I always double check my double checking.
79 GS1000S
79 GS1000S (another one)
80 GSX750
80 GS550
80 CB650 cafe racer
75 PC50 - the one with OHV and pedals...
75 TS100 - being ridden (suicidally) by my fatherComment
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stain
Installed ajustable gears dead center of slots. Set timing marks as--#1 on exhaust gear flush with head at timing mark T1-4. Slots on cams facing each other at TDC. Ran bike. Found true TDC. Remove all valve lash on #1 intake and exhaust valve. Proceeded to measure and adjust cams. Remeasured 8-10 times each side.
What I can't understand is that if I set the gears off a tooth wouldn't my measurements be way off? If the gears were off would there even be enough adjustment in the slots to get correct numbers? It seems that exhust valve is the one touching the piston.
The head is cut 40 thouComment
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sharpy
Skimming the head will alter cam timing and make the cam chain "too long" But doing what you do should fix that. (i presume) Have a look down the LHS for cam timing instructions...
The simply things that you miss are the ones that make your brain hurt. Could be worse, you could have just used the starter button to wind it over instead of by hand. Must be something you missed, sorryComment
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Guest
With the TDC1&4 and the notches facing each other are the valves on #1 all closed?
How many chain links are between #2 and #3 sprocket arrow? Did you count the links above the arrows?
You can install the cam sprockets 180 off. Ask me how I know
How did you find TDC? Was it close to the stock marks?Last edited by Guest; 06-05-2011, 02:21 PM.Comment
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stain
I just checked true TDC again. True TDC was different than the factory marks by about the width of the mark.
Slots in cams facing inwards, All marks on gears as they should be.
The valves at #1 cylinder (left) are NOT fully closed, the cam is just starting to come on to the shims. They ARE closed on #4 (right)
I degreed the cams from #1 (left) cylinder.
20 pins between marks 2 on the exhaust gear and #3 on intake gear
I see how it can be easy to put the gears on 180 offComment
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stain
Got it figured out. Thanks to the few that REALLY tried to help.
The cams WERE degreed correctly and the tool was set correctly.
Thanks RayComment
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sharpy
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