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#1002537 - 12/20/17 01:25 AM Re: Annual Service and Cam Alignment [Re: AZgman]  
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LAF Offline
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Originally Posted by AZgman
While my cams were only slightly out of phase, my bike starts noticeably faster than before. It used to always start with a pop and now it just lights up.


Well since you need to remove the cam position sensor on the left side to adjust the valve I wonder if it was off and then put back on in the correct position?

Regardless cams should be adjusted to spec using the tools. IMHO it is another quality control issue as there is no way for cams to "slip" or jump out of time, or because of the cam chain stretching. Since the two cams and the cam chain are connected by three sprockets or gears, no way for cams to jump out of time. I do not know for sure but I see no way once cams are aligned for them to ever be out again. If one I did comes back in 12K and is out I will for sure eat crow.


Lee

17 Black GSW Low
#1002560 - 12/20/17 05:14 PM Re: Annual Service and Cam Alignment [Re: Limecreek]  
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92Merc Offline
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LAF, you wouldn't happen to be going to the Un-Rally in SD next summer? I would love to see the whole process in person.


2015 Ebony Metallic R1200RT (Present)
1999 Honda Shadow Aero 1100 (17 years, Gone)
1995 Honda Shadow VLX (2 years, Long Gone)
#1002581 - 12/21/17 02:50 AM Re: Annual Service and Cam Alignment [Re: Limecreek]  
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LAF Offline
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I am going to Iowa for the National.

Since it is not really riding country I may do some there.


Lee

17 Black GSW Low
#1002589 - 12/21/17 03:51 PM Re: Annual Service and Cam Alignment [Re: Limecreek]  
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fastlarry Offline
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Southern Ohio
Why would cam timing ever change once it is set? and correctly one would hope.


Larry
2016 BMW R1200RT
#1002616 - 12/22/17 02:10 PM Re: Annual Service and Cam Alignment [Re: fastlarry]  
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PadG Offline
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Solon, OH
Cam timing shouldn't change until you get some stretching in the cam chain, and that could take a while.


2015 R1200RT (San Marino Blue Met.)
Once Upon a Time........
1963 Norton Dominator 650 SS
1960 Triumph Bonneville
1960 Triumph Thunderbird
1952 Triumph Thunderbird
1932 Tr. Tiger 500
1952 BSA Goldstar
#1002623 - 12/22/17 03:18 PM Re: Annual Service and Cam Alignment [Re: PadG]  
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realshelby Offline
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Houston, Tx
Cam chain stretch isn't the only factor with the Wethead. Since you can loosen the cam drive gear to adjust it, I assume it could move on its own. More likely they are just not adjusted perfectly when built. The cams are gear driven from a gear that is turned by the cam chain. Meaning the two cams should never be out of proper phase. But, apparently some are.

#1002624 - 12/22/17 03:53 PM Re: Annual Service and Cam Alignment [Re: realshelby]  
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Limecreek Offline
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Limecreek  Offline
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Leander, TX
Originally Posted by realshelby
Cam chain stretch isn't the only factor with the Wethead. Since you can loosen the cam drive gear to adjust it, I assume it could move on its own. More likely they are just not adjusted perfectly when built. The cams are gear driven from a gear that is turned by the cam chain. Meaning the two cams should never be out of proper phase. But, apparently some are.


Cam chain stretch on this bike over time should be negligible. And my guess is once timing is properly set it will not change by very much. I'll check again in 12K miles.

[Linked Image]

As for detecting a performance gain as a result of the adjustment? Can't say I've noticed a difference. I have noticed the fueling flat spot I had around 7K is gone, but I am attributing that to the software update I paid for 2 weeks ago.

This most recent generation of the boxer motor is really amazing - powerful, smooth, spins up quickly and a more powerful version is in development.

Last edited by Limecreek; 12/22/17 03:54 PM.
#1002648 - 12/23/17 06:29 AM Re: Annual Service and Cam Alignment [Re: Limecreek]  
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FlyingFinn Offline
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CA
I did the same job on my GSA last month. At 12K miles all the valve clearness were still well within range, but the cam timing was slightly off on one side. Just like yours, the tool didn't quite fit, so out came the crowfoot.

#1002650 - 12/23/17 11:55 AM Re: Annual Service and Cam Alignment [Re: Limecreek]  
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LAF Offline
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With three gears connecting the cams and cam chain I see no way chain stretch could make cam timing off. I mean after all that is what a cam chain tensioner is for. If you look at the pics you will see three gears it would have to jump a tooth to come out of time with each other.

I believe they are not set correctly from the factory.

Like I say if over the years I get another back that I did and it has moved, then I will need to step back and think about this in a different way.


Lee

17 Black GSW Low
#1002659 - 12/23/17 02:16 PM Re: Annual Service and Cam Alignment [Re: LAF]  
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PadG Offline
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Solon, OH
Originally Posted by LAF
With three gears connecting the cams and cam chain I see no way chain stretch could make cam timing off. I mean after all that is what a cam chain tensioner is for. If you look at the pics you will see three gears it would have to jump a tooth to come out of time with each other.

I believe they are not set correctly from the factory.

Like I say if over the years I get another back that I did and it has moved, then I will need to step back and think about this in a different way.

Tensioner will just maintain tensions so that the chain don't skip a tooth, if the slack is excessive (as in no tensioner installed). When the chain stretch, the total length of the chain grows, and that is how the timing can change. Sure, the change will be a function of how much the chain has stretched.

No arguments (as you already know) about the timing being off from the factory.


2015 R1200RT (San Marino Blue Met.)
Once Upon a Time........
1963 Norton Dominator 650 SS
1960 Triumph Bonneville
1960 Triumph Thunderbird
1952 Triumph Thunderbird
1932 Tr. Tiger 500
1952 BSA Goldstar
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