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Discussion Starter · #1 ·
I'm at a lose, I got the bike running this weekend and noticed that the right side was wet with gas, so I pulled the carbs and double checked them... sure enough one passage was blocked, re cleaned and re assembled everything today I fired her up again no problems but noticed that gas was coming from the right side air filter and it wasn't even hot, pulled the plugs and the right is dry (I do have spark) so I decided to check the compression the left is great but the right doesn't even register????? (I poured some oil in it and checked again still nothing) what should I be checking for?
 

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Discussion Starter · #3 ·
New pistons and rings, when I look into the spark plug hole I can see the intake and exhaust valves move as the piston goes up and down, I can also feel the woosh of air come out of the cylinder but if I plug the hole with my finger there's no pressure as I kick the bike over.
 

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I'd be shooting for an exhaust valve could be bad or it could simply stay a bit open when it shouldn't. Have you adjusted your valves at all?
 

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Discussion Starter · #5 ·
I did before I put the motor in the frame, but I will check that first since it means I don't have to pull the motor from the frame and rip it apart, I don't want to do that unless I HAVE to.
 

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bring piston up to TDC, using a rubber tipped air blower thingy blow low pressure air into the spark plug hole, air hissing out the carb = intake valve problem, out the exhaust = exhaust valve problem, out the crank breather = rings/holed piston. (poor mans leak down test)
 

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jayel said:
bring piston up to TDC, using a rubber tipped air blower thingy blow low pressure air into the spark plug hole, air hissing out the carb = intake valve problem, out the exhaust = exhaust valve problem, out the crank breather = rings/holed piston. (poor mans leak down test)
Yup...use a crescent wrench on the rotor bolt to hold TDC...preferably with a third hand. Pull the oil plug out too so you have another hole to listen from.
 

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Discussion Starter · #9 ·
Well I have NO clearance on the intake valve no matter what I do, does this mean I need to replace the valves?
 

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Odin said:
Well I have NO clearance on the intake valve no matter what I do, does this mean I need to replace the valves?
Does that mean you tried adjusting the clearance?
 

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Discussion Starter · #11 ·
I did, left intake and exhaust are good, right exhaust is good but the right intake will not adjust for any clearance! none, zip, nill, nada, guess I found my problem.

if I pull the valve out and grind it down, can a compression test be done without the mufflers and cam covers on?
 

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Odin said:
...if I pull the valve out and grind it down, can a compression test be done without the mufflers and cam covers on?
You can. But how would a longer valve end up in the engine?
 

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Discussion Starter · #13 ·
I never looked at it like that... the valves came out for the rebuild and then went back in. so why would I have no clearance?
 

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In these old Honda's I'm not sure. Valve spring / torsion bar off a spline unable to return the valve? Valve keepers not installed properly? I'd also say cam out of time but the other intake would likely be affected too.

Anyone else care to chime in?
 

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Odin said:
I never looked at it like that... the valves came out for the rebuild and then went back in. so why would I have no clearance?
what you would be dealing with there is the valve seating to deep into the valve seat making the stem that the tappet pushs on higher, valve stem stretch? have you followed the procedure for setting valve clearence?
 

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Discussion Starter · #16 ·
I have multiple times but the right intake has NO clearance.
the motor is now out of the frame :( and on the bench, the head is off but still in one piece and it all looks good I guess I will pull the intake cam out now and then see how all that looks.
 

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Odin said:
...the head is off but still in one piece and it all looks good I guess I will pull the intake cam out now and then see how all that looks.
You mean the valve closes?
 

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Discussion Starter · #18 ·
it looks closed, but I can spin it in place and if I check for clearance there still isn't any.
 

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Discussion Starter · #20 ·
Which one is the follower shaft?

Also I had a really good look and the valve is open, if i slide the tappet adjuster out and let the tappet fall the valve snaps shut (even heard it click closed) then looked at it and yep its closed, as soon as I put it back in place along with the tappet the valve is open.
is it possible I put the cam in backwards? here is a pic
 
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