Valve clearance
Posted: Mon Jul 03, 2023 1:52 am
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Valve clearance
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Re: Valve clearance
Posted: Mon Jul 03, 2023 2:08 am
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Re: Valve clearance
Posted: Mon Jul 03, 2023 6:30 am
The shims are available in increments of 0.05mm. Using the next size up shim will put those out of spec. or on the limit clearances in the midrange.
In 47,500 miles, I've only changed one shim on my 2012 Camhead. This was at 10,000 miles when an exhaust clearance was at 0.40mm. Changing this shim put it in the midrange at 0.35mm.
In 47,500 miles, I've only changed one shim on my 2012 Camhead. This was at 10,000 miles when an exhaust clearance was at 0.40mm. Changing this shim put it in the midrange at 0.35mm.
Re: Valve clearance
Posted: Mon Jul 03, 2023 2:03 pm
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Re: Valve clearance
Posted: Fri Jul 07, 2023 6:57 pm
Ooh, I like that tool Boxflyer. I bought the factory tool, but I sure would have made one like that, if the dimensions had been available last year. 
Re: Valve clearance
Posted: Mon Jul 17, 2023 9:13 am
Would love to know more about this process - wasn't aware that such a thing was even possible.
Re: Valve clearance
Posted: Mon Jul 17, 2023 3:48 pm
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Re: Valve clearance
Posted: Tue Jul 18, 2023 7:39 pm
Thanks Boxflyer, that is absolutely fascinating (and a really excellent rundown of the process) - won't be a job ill be doing anytime soon though given the special tools needed. When I did my valve clearances recently I used a steel rule against the flats of the camshaft where the index marks are to ascertain TDC. They didn't quite line up perfectly but were damn closen - maybe a degree or so off. How far out do they have to be before I need to worry about getting them reset?
Re: Valve clearance
Posted: Tue Jul 18, 2023 9:29 pm
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Re: Valve clearance
Posted: Tue Jul 18, 2023 9:49 pm
@Boxflyer I think he means the cams being out of alignment before causing an issue
Re: Valve clearance
Posted: Wed Jul 19, 2023 2:43 am
I was surprised to find that the valve timing on my 17RT was 10-20 degrees out. It evidently came that way from the factory, because it had less than 4K miles on it at the time. Cam alignment is definitely worth checking.Boxflyer wrote: ↑Mon Jul 17, 2023 3:48 pm The procedure for doing the Cam Timing on the 1200 CamHead engine is very similar to what I do frequently on the 1200/1250 WetHead/ShiftHead.
You need to set and lock the flywheel/crankshaft at TDC with a specific pin that fits in an open hole on the RH side of the rear of the engine block.
The side you are going to be working on will have the arrows on the ends of the Cams pointing towards each other.
Then you remove the existing Cam Chain Tensioner and install the Cam Chain Tensioner Tool with the proper 15mm Sleeve.
Tighten the CCT Tool until it clicks 3 times as determined by it's internal spring.
Now that the engine and valve train are positioned properly, you attempt to fit the Cam Alignment Jig on the ends of the cams. If the fixture does not slip onto the cams, you loosen the bolts that are binding the cam chain gears to the cams themselves and rotate the cams until the Cam Alignment Jig slips onto the cam flats. Leave the Cam Alignment Jig installed to tighten the Cam Bolts.
Lastly, you retorque the bolts holding the cam chain gears to the camshaft, and you can remove the Cam Alignment Jig and replace the Cam Chain Tensioner.
While the engine is at TDC for that cylinder, it is an appropriate time to check valve clearances and adjust if needed.
Remove the TDC pin, rotate the crankshaft 1 revolution, reinstall the TDC pin and the engine is now at TDC on the other cylinder and repeat the steps from the first side.