[kbennett2000]

A few years ago I had a Suzuki C-50. One of the Suzuki forum members came up with a way to adjust the valves without having to use feeler gauges. This made valve adjustments MUCH simplier and quicker! He calculated the degrees of rotation the screw would need to be turned out from where it first makes contact with the valve.



Here's how it worked:

.75mm pitch = .02952756" per revolution = .000082" per degree

intake .003" to .005" = 36-60 degrees (call it 45)

exhaust .007" to .009" = 85-109 degrees (call it 90)



So, to achieve the clearance for the intake valve, loosen the lock nut, screw the tappet down until it touches the top of the valve, and then back it off 45 degrees (1/8 turn) Same thing for the exhaust, back off 90 degrees (1/4 turn).



Does anyone know what the thread pitch on the TW's valve tappet screw is?

 

[Mhurchu]

That's brilliant,

you don't need to know the pitch of the thread. just do as you sujest using 45* and 90*, rotate the engine 360* and test with a gauge. if it's not spot on try again at lets say 90* and 135*. Im gonna look into this next time around.

*)

 

[-Jake-]

I didn't think using feeler gauges was all that tough...

 

[Bullspit]

How do you measure the rotation? Seems like it is a ballpark guess to me. I think I will continue to use the feeler gauge!

 

[atleastbehandy]

They are 0.75mm pitch (and 5mm dia).

 

[jflynn]

How do you measure the rotation? Seems like it is a ballpark guess to me.

That's a small ballpark. 45 degrees is one eighth a turn (the distance an hour hand moves from 12 to 1:30 on a clock face), and 90 degrees is a quarter turn (12 to 3). I would feel comfortable doing this. Smaller adjustments would be sketchy.

 

[n2o2diver]

This sounds like a huge pain in the ass to try and remember. It takes 2 minutes to just do it right! I'm a pilot and I love using rules of thumb, but we are talking about precise measurements in this case....so measure!

 

[mrbracket]

I like your idea, the logic makes sense... But for some reason I just like feeling like I'm being really precise with the feeler gauges, I dunno, I guess I have a tool addition..

I like these tools:



TW200 valve adjustment aids



But then again, I'm a tool junkie!