I recommend that EVERY R1200 or R1250 WetHead or ShiftHead engine gets an all important "First Look" at both the Cam Timing and the Valve Clearances.
It does not make sense to do it anytime before that mileage as the engine is built pretty well from the factory, and needs all of the components in the Valve Train to wear in and be normalized.
I've done about 120 Cam Timing and Valve Clearance checks on R1200 and R1250 WetHead/ShiftHead bikes and about 90% of the engines need some small adjustment to the Cam Timing as well as setting the Valve Clearances to what I believe are the "optimum" values of 0.12mm for the Intake and 0.36mm for the Exhaust.
My experience is that once the Cam Timing is set at about the 12k miles point, that it will almost NEVER change for upwards of 100k miles.
If you set the valves at the values I recommend, then the valves are not so annoying with the ticking that lots of folks say "that they all sound that way"...they don't need to.
The valves may also not need to be adjusted until somewhere around 100k. My experience also shows that clearances OPEN up vs getting tighter.
Lots of reports of hard starting, poor fuel economy, and degraded performance have been solved by doing an initial Cam Timing that includes correcting the LH Exhaust Cam Timing Reluctor input to the ECU.
I've posted this article on other Forums, so will paste it in here for those of you that may not be frequent visitors to the websites that I participate on the most.
Hope this helps,
Brad Smith
Boxflyer
Why we check Cam Timing on WetHead / ShiftHead Boxers
My belief is that the cam timing IS correctly set right from the assembly line.
When a WetHead/ShiftHead gets somewhere between 10-12k miles, all the valve train finally normalizes the wear and settles in to this state for the next 100k miles or so.
Thinking about what we do to check/set the cam timing, it makes sense to me why we need to do this early on in the typical service for these WetHead engines.
For the LH cylinder my observation is like this….inserting the 8mm TDC locking pin in the perimeter of the alternator rotor has a very small tolerance in that slot or it would get stuck there.
This LH side cam chain is driven from a sprocket on the crankshaft just between the alternator and the rod journals, so this is the shorter of the 2 sides to transfer rotation out to the cams. Both the pulling, top side of the chain, and tensioner bottom side, of the chain slide along about 8 inches of phenolic rails that are prone to some grooves from the edges of the chain links as they break in initially. All the links, (102) on this side, as well as the sprockets have lots of contact points that change as they initially wear in.
Then the sprocket shaft has the drive gear that rotates the cam gears on both Int and Exh cams…again some gear face contact wear-in is normal.
The RH cylinder has the added driveline parts before getting to the drive sprocket at the cams …there is the large gear on the front end of the crankshaft that drives the smaller gear on the clutch basket and then back thru the clutch/counter balance shaft to a similar sprocket for the 106 link chain going out to the cam drive gear.
The RH side chain has more distance from the counter balance shaft drive sprocket that is lower in the engine than the LH side driven straight out from the crankshaft.
(The ShiftHead 1250 has a link chain vs a roller chain so the left side has 130 links and the right side has 136 links)
The engineers determined that the specific pressure applied from the Cam Chain Tensioner Tool standardizes the removal of the clearance/spaces all along the components just listed to use the Cam Alignment Jig on the flats on the ends of the cams and correctly align the 2 cams for optimal operation.
Pretty convoluted description to point out that there is some normal play in all these components that we are dealing with after initial break-in to reset what the factory set during the buildup of the engine.
If you are still awake after all that, I hope you have success setting the cam timing when you get to it sometime after 10k miles minimum break-in.
It’s my experience from doing well over 100 of these Cam Timing checks that about 85-90% of the cams on each side have to be adjusted after initial break-in.
This will give you easier starting, smoother idle, smoother throttle response throughout the RPM range, and possibly better gas mileage (that’s a guess since I don’t know anyone that seeks MPG over Smiles Per Mile!)
It does not make sense to do it anytime before that mileage as the engine is built pretty well from the factory, and needs all of the components in the Valve Train to wear in and be normalized.
I've done about 120 Cam Timing and Valve Clearance checks on R1200 and R1250 WetHead/ShiftHead bikes and about 90% of the engines need some small adjustment to the Cam Timing as well as setting the Valve Clearances to what I believe are the "optimum" values of 0.12mm for the Intake and 0.36mm for the Exhaust.
My experience is that once the Cam Timing is set at about the 12k miles point, that it will almost NEVER change for upwards of 100k miles.
If you set the valves at the values I recommend, then the valves are not so annoying with the ticking that lots of folks say "that they all sound that way"...they don't need to.
The valves may also not need to be adjusted until somewhere around 100k. My experience also shows that clearances OPEN up vs getting tighter.
Lots of reports of hard starting, poor fuel economy, and degraded performance have been solved by doing an initial Cam Timing that includes correcting the LH Exhaust Cam Timing Reluctor input to the ECU.
I've posted this article on other Forums, so will paste it in here for those of you that may not be frequent visitors to the websites that I participate on the most.
Hope this helps,
Brad Smith
Boxflyer
Why we check Cam Timing on WetHead / ShiftHead Boxers
My belief is that the cam timing IS correctly set right from the assembly line.
When a WetHead/ShiftHead gets somewhere between 10-12k miles, all the valve train finally normalizes the wear and settles in to this state for the next 100k miles or so.
Thinking about what we do to check/set the cam timing, it makes sense to me why we need to do this early on in the typical service for these WetHead engines.
For the LH cylinder my observation is like this….inserting the 8mm TDC locking pin in the perimeter of the alternator rotor has a very small tolerance in that slot or it would get stuck there.
This LH side cam chain is driven from a sprocket on the crankshaft just between the alternator and the rod journals, so this is the shorter of the 2 sides to transfer rotation out to the cams. Both the pulling, top side of the chain, and tensioner bottom side, of the chain slide along about 8 inches of phenolic rails that are prone to some grooves from the edges of the chain links as they break in initially. All the links, (102) on this side, as well as the sprockets have lots of contact points that change as they initially wear in.
Then the sprocket shaft has the drive gear that rotates the cam gears on both Int and Exh cams…again some gear face contact wear-in is normal.
The RH cylinder has the added driveline parts before getting to the drive sprocket at the cams …there is the large gear on the front end of the crankshaft that drives the smaller gear on the clutch basket and then back thru the clutch/counter balance shaft to a similar sprocket for the 106 link chain going out to the cam drive gear.
The RH side chain has more distance from the counter balance shaft drive sprocket that is lower in the engine than the LH side driven straight out from the crankshaft.
(The ShiftHead 1250 has a link chain vs a roller chain so the left side has 130 links and the right side has 136 links)
The engineers determined that the specific pressure applied from the Cam Chain Tensioner Tool standardizes the removal of the clearance/spaces all along the components just listed to use the Cam Alignment Jig on the flats on the ends of the cams and correctly align the 2 cams for optimal operation.
Pretty convoluted description to point out that there is some normal play in all these components that we are dealing with after initial break-in to reset what the factory set during the buildup of the engine.
If you are still awake after all that, I hope you have success setting the cam timing when you get to it sometime after 10k miles minimum break-in.
It’s my experience from doing well over 100 of these Cam Timing checks that about 85-90% of the cams on each side have to be adjusted after initial break-in.
This will give you easier starting, smoother idle, smoother throttle response throughout the RPM range, and possibly better gas mileage (that’s a guess since I don’t know anyone that seeks MPG over Smiles Per Mile!)