valve check

[schrader]

HELP when following Freds videos for the valve check my dvd player skipped the section that explained to set the timing so piston #1 is at tdc before removing the cams. I Don't know if piston #1 was at tdc or piston 34 was a tdc when I removed the cams. How can I check.

Thanks
Corey

[B.D.F.]

You cannot but it does not matter anyway. Just leave the crankshaft at the -0- position and install the cams per the service manual and all will be well.

The crankshaft makes two revolutions per the cam's one revolution so you can install the cams at either -0- position (called Top Dead Center, TDC). Once the cams are removed, there is no longer a 'correct' or better position.

By the way, technically it is said that there are 720 crankshaft degrees in a full engine cycle (two full revolutions). The cams can be timed to zero (cam degrees) when the crankshaft is either at -0- degrees or 360 degrees.

Brian

HELP when following Freds videos for the valve check my dvd player skipped the section that explained to set the timing so piston #1 is at tdc before removing the cams. I Don't know if piston #1 was at tdc or piston 34 was a tdc when I removed the cams. How can I check.

Thanks
Corey

[koval68]

Isn't it too soon for valve check, Haroldo Corey? How many kilometers on your bike?
Anyway, good luck with your valve check! You've got nothing to worry about, with Brian's help you'll have it done in no time!

[schrader]

I have 30,000km on the bike now, one valve was within spec. So you are saying I can install the cams with #4 or #1 at tdc. I am confused on this. If I install the cams as per instruction for #1 at tdc and the crank is really at #4 tdc am I not off 180 degrees?

[Freddy]

I have 30,000km on the bike now, one valve was within spec. So you are saying I can install the cams with #4 or #1 at tdc. I am confused on this. If I install the cams as per instruction for #1 at tdc and the crank is really at #4 tdc am I not off 180 degrees?

No.  I & 4 are both at TDC together as you see.  The camhafts determine which one is at the end of the compression stroke and which at end of exhaust.  360 degree turn of crank then one is and end of exh stroke and the other comp - 2 turns of crank for 1 turn of cams.  So it doesn't matter.

[B.D.F.]

Not sure who you are talking to but....

The timing mark on the crankshaft indicating #1, #4 means that both pistons, #1 and #4 are at TDC (all the way to the top of the cylinders, or Top Dead Center) at the same time.

To time a C-14 with the CAMS ALREADY OUT: turn the crankshaft clockwise until the timing marks align per the service manual, pg. 2-24, second image down from the top. Note: it is fine to turn the engine with the camshafts removed but ALWAYS turn the engine in the correct direction and NEVER backwards! If you go past the timing mark, go all the way around again to align the marks, do not turn the crankshaft backwards.

Once the crankshaft is timed, install the camshafts so that they are also timed according to the timing marks on both camshafts, per manual page 5-18. Further instructions for cam timing can be found on manual pages 5-18 through 5-23. Once the cams are installed, the saddle bearing caps are tight and the timing looks correct, turn the engine gently forward until the crankshaft comes back around to the timing marks; the cams will now be timed but the 'wrong way' from the manual. Continue to turn the crankshaft another full revolution to again align with the timing marks and both cams will be in time with the timing marks on each camshaft. If they are not correctly timed, you are one or more timing chain links off on the timing- the mistimed cam must be removed and reinstalled in the correct position. If there is any significant resistance while turning the engine stop immediately.

Another way to time the cams is to count the number of timing chain links between the centerline of each sprocket. Unfortunately the manual is not clear on the number of links between the exhaust cam and the crankshaft although it does mention that there are 30 links between the outer sprocket points of the two cams.

Brian

I have 30,000km on the bike now, one valve was within spec. So you are saying I can install the cams with #4 or #1 at tdc. I am confused on this. If I install the cams as per instruction for #1 at tdc and the crank is really at #4 tdc am I not off 180 degrees?

[schrader]

Ok I think I got it just waiting on the shims and then I will reassemble as per your instructions.

Thanks
Corey

[B.D.F.]

Great.

It is not a difficult job but it does require attention to detail as well as knowing when a cam is 'in time' and / or close enough. The lines may not align <exactly> as the photos show they do, or as well as one would hope but the key is to know if you are one tooth off or not.

My advice to everyone is to go slow, think about what you are doing and seeing, and stop and ask for help if you are unsure what you are seeing or think you should be seeing. The whole procedure will make sense and you should not shrug off any pesky thoughts that 'that isn't right' off without investigating. Help is available, both here as well as places like motorcycle dealers (most of them really will help you even if you are doing the job yourself) and even general mechanics.

I wish I had a photo to show what the cam(s) look like one tooth out of time because once you see it will be very easy to avoid that situation.

Best of luck and let us know how you make out.

Brian

Ok I think I got it just waiting on the shims and then I will reassemble as per your instructions.

Thanks
Corey

[Summit670]

Just curious if you guys are using 1 feeler guage at a time to get the measurements or if you combine feeler guages (on the same shim) to know what the gap is.

I've stacked two feeler gauges before to get a ballpark but that measurement didn't have to be as precise as compared to using shims.

[B.D.F.]

You have to combine feeler gauges if you want the smallest resolution. On the English measurement side, the only way to get one- half thousandths (0.0005") inches is to combine a 0.0015" feeler with another feeler (0.003 to 0.008) to get both the finest resolution along with a size in the range needed.

If you wipe two feeler gauges together with a film of oil (and there will be a film of oil all over all the gauges and you up to your elbows), they will measure the actual sum of the nominal measurements; it is actually very accurate if you check a pair of feelers with a pair of micrometers.

Brian

Just curious if you guys are using 1 feeler guage at a time to get the measurements or if you combine feeler guages (on the same shim) to know what the gap is.

I've stacked two feeler gauges before to get a ballpark but that measurement didn't have to be as precise as compared to using shims.

[Z71]

I have not had the pleasure of attempting to adjust the valves on this bike due to low mileage.  However, I have this question:  Is there a special tool available that would enable one to remove/install the shims without removing the cams?  My Mazda 626 has solid valve lifters and shim under bucket type adjusters.  There is a tool for that car that enables you to remove/install shims with the cams in place.

[lather]

I have not had the pleasure of attempting to adjust the valves on this bike due to low mileage.  However, I have this question:  Is there a special tool available that would enable one to remove/install the shims without removing the cams?  My Mazda 626 has solid valve lifters and shim under bucket type adjusters.  There is a tool for that car that enables you to remove/install shims with the cams in place.

Negative.

[texrider]

Aside from scheduled checks, one way to note that your valve clearance is going away is the higher RPM range will feel stronger. With less clearance, valve lift and duration (overlap) are increased.

Less seat contact time can eventually result in valve and head damage, and a held open valve will produce a low compression cylinder.

These will result in statements like, "It was runnin' great, then all of a sudden...." 

[B.D.F.]

As Lather said, no. It is not physically possible.

Brian

I have not had the pleasure of attempting to adjust the valves on this bike due to low mileage.  However, I have this question:  Is there a special tool available that would enable one to remove/install the shims without removing the cams?  My Mazda 626 has solid valve lifters and shim under bucket type adjusters.  There is a tool for that car that enables you to remove/install shims with the cams in place.

[schrader]

Finally got the shims in and everything re assembled, took more time than I figured it would but now I know it is right.Had everything re assembled and found two valves were a little tight so I pulled it apart and went down one more shim size. With 30,000k on the bike 15 of the 16 valves were out of spec, two were four shim sizes out.

While waiting for the shims I pulled the flies, cleaned the KN, replaced the plugs, flushed the brake/clutch fluid and fixed the leak in the valve cover gasket. Should be good for the next 30,000k, just need to wait for spring now.

Also looking for a PC since I haves pulled the flies and put a two brothers on.

Core