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Hotcams/ 686 help !

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  #11  
Old 02-22-2004, 12:31 AM
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Default Hotcams/ 686 help !

ok guys, you are scaring me [img]i/expressions/face-icon-small-sad.gif[/img] I hope it's not the JE.

the noise is not loud at all, and it's not like a constant noise, it's almost like (tick........nothing.........tick tick........nothing) and like I said b4 it almost sounds like a metal cooling down after a hard ride, except it's not. I am pretty sure the bike never made that noise b4. that and I never readjusted the valves after the first time when the cam was broken in, and that was 6 months ago. any thoughts?




thanks
 
  #12  
Old 02-22-2004, 12:40 AM
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Default Hotcams/ 686 help !

Adjust the valves and you'll know if you need to go deeper. But if it has been 6 months, you probaly need to adjust them.
 
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Old 02-22-2004, 12:45 AM
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Default Hotcams/ 686 help !

Does it make this noise when idling or when you give it gas?
What octane are you running and what plug?
Check your valves, your way over due anyway. Run a colder plug if it's the stock heat range you have in there, I would put in a 9.
 
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Old 02-22-2004, 01:07 AM
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Default Hotcams/ 686 help !

Does it make this noise when idling or when you give it gas?
it makes the noise when it's idiling.



What octane are you running and what plug?
I am running 98 octane with stock heat plug

guys with hotcam stage II, what did you set your valve clearance at?


thanks for your help guys.


 
  #15  
Old 02-22-2004, 07:02 AM
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Default Hotcams/ 686 help !

Originally posted by: Ward660R
intake: 0.20mm
exhaust: 0.25mm

Thats what I set mine at.
[img]i/expressions/face-icon-small-confused.gif[/img]

Check your cam chain tension too, its a slim possibilty and easy to check, but its more of a knocking/slap sound.
With the way your maintance practices sound do you know if it has any oil in it?[img]i/expressions/face-icon-small-wink.gif[/img]
 
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Old 02-22-2004, 07:33 AM
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Default Hotcams/ 686 help !

With the way your maintance practices sound do you know if it has any oil in it?
hehehehhe well it's funny you asked cause I found out that it had no oil last week and had no way of getting any motor oil so I ended up putting some cooking oil in there, but don't worry I made sure the oil was as heavy as the Yamaha manual says [img]i/expressions/face-icon-small-tongue.gif[/img]


Ward, thanks for your concern about my oil bro, I got that covered !


 
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Old 02-22-2004, 12:07 PM
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Default Hotcams/ 686 help !

I used .006" intake and .008" exhaust, you've got to keep a close eye on the intakes, no more than 20 hours between adjustments. I tried a little tighter on the intake one time and after the engine got good and hot, it had a mid range stumble.
 
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Old 02-22-2004, 01:33 PM
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Default Hotcams/ 686 help !

Originally posted by: UBETRUN
I used .006" intake and .008" exhaust, you've got to keep a close eye on the intakes, no more than 20 hours between adjustments. I tried a little tighter on the intake one time and after the engine got good and hot, it had a mid range stumble.
that is what hotcam told me........and that is how mine is set........
 
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Old 02-22-2004, 01:47 PM
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Default Hotcams/ 686 help !

If it ran fine for 6 months, its probably just a valve adjustment. But if that doesn't help & you decide to tear it down, check that the cam decompression mechanism is still working.
I had one in which the pin was stuck in the out position & was opening the exhaust valve on every exhaust stroke & made a terrible ticking sound.
It was also evident by not having any mid/top end due to the compression loss. To check it, rotate the decompression spring lever against the decompression cam weights & you should see the pin go in & out of the exhaust cam lobe. If its stuck in the out position, the decompression spring coulld be binding or broke.
If you experiment with different cam combinations in which you'll have to remove/install the spring more than once, you'll find that its cheap insurance to replace the spring.
 
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Old 02-22-2004, 07:25 PM
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Default Hotcams/ 686 help !

Thanks a lot to all of you guys.

I will check the valve clearance, and if that does not do it, I guess I will have to dig deeper into the motor.

thanks again

Ahmed
 



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