does anyone know yet if the procedures for adjusting the valves and checking cam timing is the same for the shiftcam motor as the 1200w motor? And will my cam tensioning tool, tdc tool and the cam timing tool from my 2015 work on the new motor? Also are the service intervals the same ? I plan to buy a new r1250rt in about a year and am curious to learn if i will still be able to do my own service.Thanks
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1250 maintenance questions?
- Thread starter jimbem
- Start date
pglaves
#13338
I have no idea as to the specific answers to your question, but would also venture that even if the procedure is different, if you can read the instructions for your current bike and do the maintenance then you will be able to read and/or see the instructions for the new bike and do that too. Maybe a new tool will be required but valve clearances are valve clearances. Measure and get them right.
pauls1150
MOA #24991, south of Los Angeles
Just a wag, but I agree that the tension is different; also, while the base circle has to be the same, would they actually wear at identical rates? Fer now (with zero experience on these), I'd say check both places and adjust the tighter one for correct clearance.
pappy35
New member
Another WAG: The base circle area sees no load due to the clearance. When the bike is hot it close up a lot but it should never be in contact while running. So, no load means no wear to the cam at that location. Knowing that, if/when I own one, I'd probably still check it at both positions , assuming of course that it can be easily moved, because I can be anal about such things.
FWIW I had my R1200RS valves checked twice (over approx 35k miles) by the dealer, found no adjustment needed. The design is for wear to be complementing, largely self compensating. Great Engineering. I'm not saying checking is not needed...just that the issue is MUCH less than it was on the old airheads for instance.
Unless engine maintenance is part of your joy of owernship, worrying about tools for this moot.
Since my engine is well settled in now, I will not even think about it till I'm well over 70k miles.
Unless engine maintenance is part of your joy of owernship, worrying about tools for this moot.
Since my engine is well settled in now, I will not even think about it till I'm well over 70k miles.
pauls1150
MOA #24991, south of Los Angeles
Regarding that cam base circle:
If your valve's adjustment is too tight, the follower rides on the base circle (the "flat") continually, and this will increase the wear there, and on the follower. (A drastic case would even prevent the valve from fully closing.) Which flat wears more quickly would then depend on which lobe the selector mechanism decides to spend more time on.
How do they get tight?
1) Improper shimming during setup or maintenance.
2) Normal wear - as the valve seat gets pounded by the valve, and the backside of the valve hammers the seat, they get a little thinner and/or deform. This issue is typically more common on the exhaust side due to the higher temperatures there than on the intake; it hasn't been a "typical problem" for decades but can still happen.
Several members on this forum have exclaimed "I set my valves Exactly to the factory spec and will not deviate from this", either because: 1) "The factory is always right", or 2) "Somebody on the web said that I'll get a quarter horsepower more out of it". (This is aside from the fact that anybody who can set valves can also show, at will, that setting them a teeny bit loose makes starting easier and lets the engine spin up AND down easier; it will also allow that adjustment to last longer. I won't get into how valve adjustment affects intake vacuum and throttle-body balance.)
Since the clearance tightens up anyway with wear (on oilheads, Ks, and subsequent models), these folks are at greater risk.
It's great that these items need much less maintenance these days (and we have yet to build up a history with this tech on the bikes), but that doesn't mean you can ignore it completely.
I also agree that the chain tension itself likely is different, too: it's a completely different type of chain, which resists wear and twisting better than a single-run chain, and it's "probably" manufactured (an educated wag) with different clearances between its side plates and roller pins.
If your valve's adjustment is too tight, the follower rides on the base circle (the "flat") continually, and this will increase the wear there, and on the follower. (A drastic case would even prevent the valve from fully closing.) Which flat wears more quickly would then depend on which lobe the selector mechanism decides to spend more time on.
How do they get tight?
1) Improper shimming during setup or maintenance.
2) Normal wear - as the valve seat gets pounded by the valve, and the backside of the valve hammers the seat, they get a little thinner and/or deform. This issue is typically more common on the exhaust side due to the higher temperatures there than on the intake; it hasn't been a "typical problem" for decades but can still happen.
Several members on this forum have exclaimed "I set my valves Exactly to the factory spec and will not deviate from this", either because: 1) "The factory is always right", or 2) "Somebody on the web said that I'll get a quarter horsepower more out of it". (This is aside from the fact that anybody who can set valves can also show, at will, that setting them a teeny bit loose makes starting easier and lets the engine spin up AND down easier; it will also allow that adjustment to last longer. I won't get into how valve adjustment affects intake vacuum and throttle-body balance.)
Since the clearance tightens up anyway with wear (on oilheads, Ks, and subsequent models), these folks are at greater risk.
It's great that these items need much less maintenance these days (and we have yet to build up a history with this tech on the bikes), but that doesn't mean you can ignore it completely.
I also agree that the chain tension itself likely is different, too: it's a completely different type of chain, which resists wear and twisting better than a single-run chain, and it's "probably" manufactured (an educated wag) with different clearances between its side plates and roller pins.
