adjusting valves, help!

[Enjine]

5) put your thumb over the spark plug to feel the compression rising
probably a dumb question but am i feeling for the air pressure pulling into the cylinder or pushing out?

6) when the LT mark comes up, that is when you gap the left valves.
7) repeat for the other side.
when repeating for the other side, should i be using the RT notch instead of the LT? or again the LT?

 

[HoughMade]

- Pushing out
- LT for left cylinder (while facing forward) RT for right cylinder.

 

[Kdog]

I been setting my valves on my 77 xs400. I did have to brace the wrench to keep the flywheel from turning, but I agree with the "don't over think it. I aim for a the middle feeler gauge as it seems to keep you from being too loose or too tight. One mistake I made was misreading feeler gauge I first had watch out for MM to Inches, and watch your decimals i.e. .005 not .05…..my valves seemed to be too tight, will see as I am going to re-time also later tonight, fingers crossed. https://plus.google.com/photos/106847003328795024378/albums/5872271808417190353?authkey=CIXC05PmoIPVCQ

 

[motoTrooper]

I always aim for the valve gaps to be on the loose end of tolerance as directed by a valve expert that does racing engines. Better to have a tight sealing head for best compression. Yeah the trade off is usually hp vs. torque but these are not high hp engines so better to access all the torque available for a streetbike.

 

[Kdog]

Do you think I should re-do my valves aiming for the largest feeler??

 

[motoTrooper]

I wouldn't grip too hard over it, if you're already in the mode and everything is still apart and accessible the extra practice of doing it is simple. But if you want to wait until the next time, so be it. It's easy to get OCD over this stuff.

 

[Kdog]

Yeah I agree on that….I can do i next time I change oil…. Do you know anywhere if I ever wanted to rebuild the engine I could find the motor parts to do so?

Everything is stock, at this time…I would like it to be reliable, over running faster or hot rodding. I had popping out of the mufflers even after I sealed the mufflers and headers very well….so I went to the valves...

 

[Scorpio1963]

Well I can see that I definately did my adjustent wrong

 

[Kdog]

ok, I went home at lunch, and checked my timing, with a light, dead on. Added fuel to an external tank running to the carbs. check spark at plugs, appears to be great. Hit the starter, round and round, but will not fire….

Could it be possible I set the valves on the wrong stroke? I am pretty sure I set the valves on each side at TDC as I can see in the plug hole with a flash light and took a good bit of time setting them.

This bike ran great, then quit, which started my process of elimination…new coils, points plugs, wires, carbs rebuilt, it is all stock.

Since it ran great, but would not run slow well, and would stall, and the fact I never checked the valves I thought I should, and did, but now it still will not fire.

If I adjusted the valves on the wrong stroke, could that cause this problem?

 

[Kdog]

not sure how to remove a double post….sorry

 

[Scorpio1963]

Ok Drewps my turn Im totaly lost what side is this cover on that I have to take off?If there away to make this adjustment with out taking the cover off?Or am in for the the biggest pia in my life?Gosh dang it I wish I would have never messed with them the other day this bike is now become a pain in my ass.Thanks

 

[drewpy]

cover as in for timing?

make sure the bike is on the main stand or it will do an oil wee wee on the floor!

its the left side as you sit on the bike.

I have a windowed cover made and never have to take it off

TDC is when the air is forcing your thumb off the spark plug hole and the corresponding LT or RT line, lines up. that's when valves are adjusted

 

[Scorpio1963]

Well Im ready to do the job,got all my tools I know which valve is what and a found a great online tuturial to show me the way.

 

[motoTrooper]

Just to add, usually when the motor is in the non-compression stroke, the clearance between the rocker and valve is zero (touching one another). Then it requires another 360 degree rotation to get to the proper compression stroke where there is the gap to be measured and adjusted. Hope it helps, had to learn my own hard way...

 

[Scorpio1963]

Thanks moto I can use all the extra help I can get.

 

[MrYeats]

I'm so old I remember sticking a pencil in the spark plug hole and brought it to TDC. When the pencil comes up, then just starts to go down, you are at TDC.

 

[drewpy]

I'm so old I remember sticking a pencil in the spark plug hole and brought it to TDC. When the pencil comes up, then just starts to go down, you are at TDC.

until it rests opposite the bore and snaps off inside

 

[Scorpio1963]

OUCH yeah that wouldnt be good.Anyway we can combine this thread in with the other one?Its kinda my fault by dragging it up out of the archives by doing what Im supossed to do use the search.

 

[marko472]

Thanks guy,s for the info
this forum is the whip