Valve adjustment confusion....

JP50515

XS650 Junkie
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Alright so I set my valves on my 77' again....today inlet at .006 outlet at .012. I'm kind of confused now, I can still hear my valves louder than before my adjustments but the bike is pulling hard enough to lift the front tire (like an inch ha) if I try...It's like a completely different bike.....

Does anybody have a close up video with audio of their engine/valve noise?

I just need a properly tuned engine to compare this thing to.


Thanks
 
Those are really big gaps, it's not surprising they are loud. Where did you get those from? try .003" intake and .006" exhaust. I use .0025 intake. Have you set the cam chain using the running method?

Seems to me 5twins showed a first year spec sheet with those numbers but they changed it for 71 and after.
They sure kept moving the spec around though.
 
If you can stand the noise, then go with it. That's not the spec for your model though. It's accepted practice to use .003" for the intake and .006" for the exhaust on all models. The spec given in the service data sheet from Yamaha actually used .002" on the intakes but I wouldn't. Here's a link to the sheet .....

77-78ServiceData.jpg
 
I apologize, let me correct myself here. The numbers above are what I set them to the other day and they were screaming at me, I then readjusted them to .002" and .006" and I can still hear them over the exhaust, not nearly as loud as before but louder than before any adjustments... however my bike is running like a champ with them set like this.

P.S. I adjusted the cam chain while running prior to the adjustment both times and set the timing after both times.

Thanks for the help
 
I apologize, let me correct myself here. The numbers above are what I set them to the other day and they were screaming at me, I then readjusted them to .002" and .006" and I can still hear them over the exhaust, not nearly as loud as before but louder than before any adjustments... however my bike is running like a champ with them set like this.

P.S. I adjusted the cam chain while running prior to the adjustment both times and set the timing after both times.

Thanks for the help
.003 is at tight as I would go .002 is a little tight.
question: did you set the valves while the engine was warm?
If you did that was the wrong time to adjust the valves.
The engine must be cold. I like to adjust the valves first thing in the morning.
Then I would warm up the engine and adjust the cam chain, then the timing.
Thats a good time to sync the carbs. Thats the order I would use for tuning.
 
I did not do it warm. Had been sitting over night. I'm just gonna start completely over on it. I can't hear them when I'm riding as much , but at lower rpms and idle they're loud.
 
It's been noted in many previous "valve adjustment" threads on this forum that the condition of the ends of your adjustment screws, if beat up a bit, can prevent you from setting clearance accurately. If you haven't already done so, you may want to take them completely out of the rocker arms to inspect. They are not expensive to replace. If you do need new ones, consider buying Virago valve adjustment screws - they are a "drop in" fit, just a bit shorter than stock 650 screws, and adjust with a hex key.
 
I had the noisy valve problem too. It turned out the the end of my intake valve had worn out and became concave. Even though the feeler gauge showed a good adjusment it didn't take the inset into account.
 
Stupid question and dont mean to insult but you are setting them on the side that is at the top of its compression stroke at TDC? If not your gap will appear right but as the engine moves round to the correct measuring position the gap will be much bigger giving the sort of volume you describe
 
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