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Valve Clearance Adjustment

5.6K views 66 replies 13 participants last post by  Beowulf  
#1 ·
Next Saturday, I will be doing my first valve clearance adjustment on my 2022 ATAS. I will be using the video posted below and my service manual. This will be my first valve clearance adjustment on any motorcycle.

If you have any tips or pointers, please share. I’m not looking for you to explain the entire process, but if there is a trick or tip that you found helpful, I would appreciate knowing.

While I have my gas tank off, I am also going to adjust my crankcase breather hose as oil has been leaking all over my bike for the last 10k miles (I suspect it wasn’t put back correctly when a new wiring harness was installed by my dealer).

I will update this thread as I complete the maintenance.

Thanks,
Dillon

 
#2 ·
I had problems with the right hand radiator, don't recall exactly what but somehow I think I dislodged the cowling and it was a nightmare to get back into the correct position. When I next do the valves I will also do a coolant replacement and thus remove the lower hose on the right radiator so it can be swung out of the way or maybe even remove the radiator completely which should make life a lot easier.
 
#6 ·
I'd use a 5 year coolant.

If you need shims just order the ones you need.

Definitely measure the clearances in mm, use a 17 blade feeler gauge set comprising of 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.15, 0.20, 0.25, 0.30, 0.40, 0.50, 0.75 and 1 mm feelers. My preference here is to take the feeler blades apart and use them in pairs to measure the clearance where 0.09 + 0.07 = 0.16mm, 0.09 + 0.08 = 0.17 mm, 0010 + 0.08 is 0.18 and 0.15 + 0.08 = 0.23, 0.15 + 0.09 = 0.24 and 0.15+ 0.10 = 0.25 etc. If you mess around using the thinner blades (example 0.20 + 0.03 = 0.23) the thinner blades can deform and give a false feel.
 
#7 ·
Just adjusted the valves in my 2016 AT last weekend. This might be obvious, but do reserve a lot of time for the job, especially since this is your first time (like it was for me). Even though you have a step-by-step guide for help, you can take the time this job would take from the dealership and "multiply it with pi."

The guy in the video used covers to protect components from foreign materials. That's a good habit, but if possible, use a) covers with bright colors and b) use covers that go around the outer surfaces. This reduces the risk of the protective material to remain in the system after the reassembly. That is a suprisingly frequent especially when people get exhausted/tired (source: I used to work as an FME coordinator in a power plant)
 
#9 ·
I did quite a few other maintenance/installation works at the same time, and took a couple of small breaks. But if I had to guess the time solely for the valve adjustments, I would say some 6–7 h of active working including disassembly and reassembly (somewhat conservative estimation). Though I only had to adjust exhaust valves so that saved me some disassembling.
 
#10 ·
A lot of information is available via search. I'd point out these things:

I used information from lots of sources, including the shop manual.
Time.
  • I am notoriously slow and will go on side expeditions when I am working ("hey...I think I'll clean this part now"). That being said, this took a lot of time, even for me. I adjusted the valves and balanced the throttle bodies on my BMW R1100s oil head in less than 90 minutes. This was something completely different.
  • My schedule was this:
    • Friday after work: removed front bodywork and radiators. That was enough - I was tired. 2 hours
    • Saturday: remove tank and eventually got to the valve cover. Called it a day at hour 4.
    • Sunday: checked valves (no adjustment needed - all within spec, though one intake valve was at the limit), changed plugs and began re-assembly. Completed all reassembly except radiators and bodywork: 5 hours.
    • Work week (Mon and Tue): Bodywork, air filters replaced and radiators back. Another 3 hours. I have to admit, the cowling and fan attachment to the radiator was a total mind-puzzle for me.
    • So, I'm more like 14 hours - but like I said, I am slow, and take lots of notes.
Tips

  • I used a new cover gasket. I'm like that. The "old" one was still in good shape but the new one was easier to fit for reassembly.
  • I agree with what Art said above. Get a good feeler gauge set with gradations he suggested.
  • If you haven't been inside the AT before, take lots of pictures, and from various angles as you take things apart. Take more pictures than you think you need. And take notes on how things re-assemble. Routing diagrams in the shop manual help on reassembly.
  • Keep track of sections in the manual that pertain to the area you are working on. Refer back on re-assembly. There will be things that matter there.
  • It's a benefit to have a helper from time to time (extra hands) especially when re-attaching the fuel tank and associated lines.
  • Do you know how every type of electrical connector comes apart? I sure don't. There was one on the radiators for the fans that stymied me. I attached an older service bulletin that shows how to make it work.

It's a do-able job, but bring realistic expectations for time required.
 

Attachments

#11 ·
Thank you very much for the detailed write up! I didn’t think to replace the cover gasket. One of the things I like about taking a motorcycle part is you are able to properly clean things. My bike is very dirty from the crankcase breather not being installed properly after getting a new wiring harness.
 
#12 ·
I did mine as part of my frame repair operation... If I were to venture a guess, I would say with dinking around and goofing off, I had about 8 hours into it.

I had the radiators off, since I was working on the frame, but I found that by loosening the bolts on the right radiator, I was able to slide the valve cover out that side, with just a little gentle pressure forward on the radiator, at the same time.

Yeah, I got to remove the cover again, once I had the radiators in place because I was not careful enough on keeping the rubber gasket in the groove.

It desn't take much, but "some" black RTV sealent in the corners of the half moon piece is needed for no leaks. Careful lowering the cover down; check the halfmoon as you do, to make sure it is straight up and down, not tilted in or out.

Good time to do plugs, if you think you need to. Caution on pulling the inner plug cables. A little twisting, prior to pulling helps break them free, but gently.

The video is good, I used it, as well, also have the shop manual, but didn't need to open it, other than to glance at the specs, just to be sure.

You will do fine, take your time and enjoy the process.
 
#37 ·
Assuming you mean the plug caps. Mine came out fine but I held the rubber rather than the lead to pull them out. You do get pliers meant for pulling them but I don't have any.
If it is just the lead has come out of the cap then it should be fine just to reinsert it I think.
 
#38 ·
I was trying to pull by the rubber plug, but accidentally pulled the lead out. The second rear plug came out after 5 minutes of back-and-forth tugging. I don’t think I broke the first one, I just pulled the lead out by accident (I wasn’t using the lead to pull).

This is proving to be more challenging than expected. Thanks for everyone giving me tips!
 
#39 · (Edited)
I can’t figure out to remove the right radiator. I tried taking the head off without removing the right radiator, but could not lift the head off.

This is proving to be much harder than I thought.

Edit: Radiator off. At this point, I am just embarrassing myself. I struggle with every step.
 
#41 ·
Removing the right radiator will certainly help pulling the valve cover out the right side. Also it will help when sliding the valve cover in from the right side with a new gasket firmly in place. A little finesse and the valve cover will set perfectly on the head. Have a look at every inch of seating for the valve cover and gasket to be sure. Then, have a look at the seating of the seals for the spark plug tubes. This will ensure you won't have an oil leak and end up repeating the process.
 
#42 ·
Tip: While rotating the crank, to position for actually checking the valve clearances, watch the intake cam lobe depressing the valve. Once the valve is on its way back up, watch closely for the intake cam lobe to go horizontal and pointing aft. At this point intake and exhaust cam lobes will be facing AWAY from each other. You are at or nearly at TDC. Look for a marking in the witness window. If you miss it, start over and watch the intake cam lobe.

This works for both cylinders.
 
#50 ·
Results: the intake valves in cylinder 1 and cylinder 2 were within spec (they were +/- 1). The exhaust valves were not in spec (they were +/- 3). Having to remove the camshaft and deal with the shim under bucket would likely add another 2 hours.

Given I expect the bike to last 200k miles, this is my 1st of 13 valve clearance checks I will have to do over the next 20 years.

Thank you to everyone who has given me tips/advice!
 
#53 ·
Results: the intake valves in cylinder 1 and cylinder 2 were within spec (they were +/- 1). The exhaust valves were not in spec (they were +/- 3). Having to remove the camshaft and deal with the shim under bucket would likely add another 2 hours.
Perhaps you have the sides swapped.
The Intakes are with the shims.
the Exhaust are with the screw and nut adjuster.
 
#55 ·
I am struggling to get my airbox back together. I can’t get the airbox to seat in the throttle body, and I am also having difficulty getting the bottom hose (underneath airbox) to fit in the top of the valve cover.

Any tips? I have been at it for 2 hours with no progress.