Valve clearance

[VaR1200RT]

I just did my 60K service. The valve clearance has always measured in the same until this time. I have 1 that is slightly out of the tolerance range. Here is what I measured

Intake

Right.  Left

.202.    .203. Top

.178.    .178. Bottom

 

Exhaust

Right.  Left

.356.    .381. Top

.356.    .406. Bottom

 

The .406. Was very tight The range is .3 to .4

How critical is this To get adjusted. My dealer is backed up for about 3 weeks. Is this something I can ride for another thousand miles Until the dealer can see it or should I not ride it at all.  I have never had to adjust any of these.  This is the first time they have changed in 50 k. Should I adjust any of the other clearances ?

 

Thanks

 

 

[Boxflyer]

@VaR1200RT If you get an unusual 12k check of your valve clearances, especially that the gap opens up, after they have been consistent for the previous checks...make it a pre-service routine to run some BG44 or Chevron Techron thru the bike before doing a valve check. The ratio is about 1oz per gallon and it will help with an unusual carbon buildup that may be giving you the wider than expected clearances.

If you really feel like conducting some testing, now that you have just recorded your valve clearances...run the tank of cleaner laced fuel thru the engine and do another valve check.

You may see that your clearances are right back to where they were before. 

 

I ask all the owners of bikes that I do valve checks on to please run a tank of either of the fuel cleaners I listed above thru before I do the service.

It helps prevent false readings that lead to lots of extra work and possibly setting the valve clearances based on carbon buildup under the valve seats and not "normal" operating conditions.

 

This has been most often a problem with bikes that have made the trek up to Alaska and back. The quality of the fuel in lots of remote areas will lead to carbon buildup and much greater clearance values when checking valves.

 

Brad

[VaR1200RT]

Thanks Brad I will try that and recheck after a tank of gas

 

[VaR1200RT]

On 7/14/2023 at 10:40 PM, Boxflyer said:

@VaR1200RT If you get an unusual 12k check of your valve clearances, especially that the gap opens up, after they have been consistent for the previous checks...make it a pre-service routine to run some BG44 or Chevron Techron thru the bike before doing a valve check. The ratio is about 1oz per gallon and it will help with an unusual carbon buildup that may be giving you the wider than expected clearances.

If you really feel like conducting some testing, now that you have just recorded your valve clearances...run the tank of cleaner laced fuel thru the engine and do another valve check.

You may see that your clearances are right back to where they were before. 

 

I ask all the owners of bikes that I do valve checks on to please run a tank of either of the fuel cleaners I listed above thru before I do the service.

It helps prevent false readings that lead to lots of extra work and possibly setting the valve clearances based on carbon buildup under the valve seats and not "normal" operating conditions.

 

This has been most often a problem with bikes that have made the trek up to Alaska and back. The quality of the fuel in lots of remote areas will lead to carbon buildup and much greater clearance values when checking valves.

 

Brad

Thanks Brad. You saved me doing unnecessary work possibly putting the valves out of spec.  I did what you suggested. There one small change on the right side clearances but the left side clearances exhaust changed by .05.  I wonder if this might be due to using the side stand and that's the low side?

[rockitcity]

Correct me if I'm wrong here, but if the spec is .3 to .4 and you're at .406, you're on the loose side, right? To my knowledge, being loose is better than being tight, where the valve may not close all the way if left long enough.  I don't think you have anything to worry about for a few thousand miles, but if you are doing the valve check anyway, why not just do the adjustment? You would need the proper size shim, but the dealer probably has that, or you may be able to swap some around to get the proper clearance.  That is more trouble, though.

[walton66]

once upon a time, there was a spreadsheet writer on this site that had built a sheet with the input being the clearances and the output being the part# of the shim required if the measurement was out of range.  I have to say that in 80k miles my camhead only had one valve go slightly out of the range on the loose side.  I miked the shims and swapped one and all was well.

[Hank in WV]

Apropo of nothing, my '10 RT never did have a valve gom out of adjustment in 90,000 miles.

[VaR1200RT]

All valves are back in spec range.  The .05 I mentioned is the clearance went from .406 to .356 after running a tank of gas with Techron thru it with some high RPMs.  

 

[Hadabadachada]

Very cool

[Dave_in_TX]

On 7/14/2023 at 9:40 PM, Boxflyer said:

@VaR1200RT If you get an unusual 12k check of your valve clearances, especially that the gap opens up, after they have been consistent for the previous checks...make it a pre-service routine to run some BG44 or Chevron Techron thru the bike before doing a valve check. The ratio is about 1oz per gallon and it will help with an unusual carbon buildup that may be giving you the wider than expected clearances.

If you really feel like conducting some testing, now that you have just recorded your valve clearances...run the tank of cleaner laced fuel thru the engine and do another valve check.

You may see that your clearances are right back to where they were before. 

 

I ask all the owners of bikes that I do valve checks on to please run a tank of either of the fuel cleaners I listed above thru before I do the service.

It helps prevent false readings that lead to lots of extra work and possibly setting the valve clearances based on carbon buildup under the valve seats and not "normal" operating conditions.

 

This has been most often a problem with bikes that have made the trek up to Alaska and back. The quality of the fuel in lots of remote areas will lead to carbon buildup and much greater clearance values when checking valves.

 

Brad

I checked the valves on my new 2023 R1250GS at 6k miles because I was nearing an extended trip that might (and did) put me past 12k miles on bike. I checked again at 18k and one intake was just barely out of spec on the ;loose side. Because of the bike's relatively low mileage and the fact that I use top tier gas when available, I did not have much hope that this would bring it back within spec however, it did. In retrospect, I did put on a couple thousand miles in areas where top tier gas was nearly nonexistent.