Extended valve check intervals...EPIC intervals

Joined
Feb 5, 2011
Messages
998
Location
Maryland
Bike
Honda NT700V
Personally, I think that the first valve check should be done on any machine. Somebody could have had a bad day at the factory, so you should have that baseline check done. Once you know that the valves are properly set, it's probably not necessary to check at the 8K interval that Honda specifies. I did a check before and after my 15K mile trip to Alaska last year and the valves were still in spec. The bike has 58K on it now and I will do the check every 16K from now on.
 

junglejim

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Apr 26, 2012
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2,119
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Northern WI
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Tiger 800, NT sold
Just checked my valves after about 20K miles. Exhaust valves were perfect and intakes were just a bit tight. Set them back to the middle and don't plan to open it up again for at least another 25K miles.
 

Coyote Chris

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Aug 25, 2011
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4,386
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Spokane
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10 Red NT 14 FJR, 17 XT
I am with bicyclist. I had the dealer do the first one ( and write them down), even though I am a Govt Lic. Aircraft Mechanic. I did the second one at about 10k and there was little change. I feel better doing them myself because I can afford to take my time, make sure everything is correct and I use a torque wrench. After one learns the 2 tricks, there really isn't much to doing the valves. As far as extended intervals, I will say that over the last 50 years I have set the screw adjuster valves on many Yamahas, Hondas, and my Concours C10. I never have seen any major changes over the prescribed intervals except for my C10. I have been setting the valves on that bike now for over 10 years and 38k miles and once went a bit long and saw an exhaust valve clearance decrease of .002. Not super dangerous but I reset the valve and watched it over the next two checks very carefully and it was fine after that....And yes, you may hear loose clearances but sometimes they come on so slowly you don't notice it...tight clearances you don't hear...and if they do get too tight, you can burn a valve and then notice a decrease in performance. I let the dealer do my Honda CRV's (car) valves at the prescribed interval of 100,000 miles (screw adjuster) and when I drove the car away from the dealer, I could notice the lack of clatter. Two valves were out of spec. If I were paying someone $385 to set the valves on the NT, I would have the first one done at 600 and have the second one done about 10,000 and if there was no change, I would use probably 20K for an interval. Since I can do them myself, I will now do them at 10,000 and use the results as an indication of engine health.....(or to put it another way, it makes me feel good! LOL!)

Thanks Bicyclist. Definitely food for thought
 

Coyote Chris

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Aug 25, 2011
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4,386
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Spokane
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10 Red NT 14 FJR, 17 XT
Very true. Those escorts had Non interference engines. When the cam belt broke, you got a tow and they put on a new belt. The 1984 Civics had interference engines. When the cam belt broke, the pistons smashed into the valves. If you drive a car with a belt driven cam, it pays to know if you have an interference engine or a non interference engine if you want to stretch the interval. Thankfully, many engines are now cam chain driven.
Chris who doesn't enjoy replacing his wife's cam belts....

The pre-91 Ford Escorts would bounce valves off cylinders if a timing belt broke. I guess that got expensive enough that it go Ford's attention. I had a 92 Escort and one of the questions I got an answer to before I bought it was: What happens when a timing belt breaks. On the post '91s, the answer was, "Nothing. It just stops."
 
Joined
Jun 5, 2011
Messages
630
Location
Western Washington
Bike
2010 NT700V, 2015 CB500X
I just finished my 4th check of valve clearances at ~34K miles. Here is the history of my valve adjustments.

8K- no adjustment
16K (performed at 20K) - Adjusted front cylinder exhaust valves from .07" to .08". Spec is .07 to .09" for exhaust valves.
24K- no adjustments
32K (performed at 34K)- Adjusted rear cylinder exhaust valves from .07" to .08". Adjusted one rear intakes from .05 to .06" to match other intake. Spec is .05 to .07" for intake valves.

Points of interest I noted during the valve adjustment for everyone to consider.

-All four of my exhaust valves have now been adjusted once, the fronts at 20K, rears at 34K. None of the clearances were out of spec, but were getting tighter and needed to be centered. I was happy with my rear exhaust valves at 20K and 25K (actual miles when checked), but not at 34K.

-Through trial & error(s) I found an easy way of setting the valve is to view the change in the adjustment screw slot position with the minimum and maximum spec feeler gauge inserted and then set the screw to the mid position and lock it. For example, the exhaust valve spec is .07 to .09", so I inserted each of those feeler gauges and tighten the screw until snug, then check the adjustment screw slot position. The change for the adjustment screw slot position is extremely small, I found that it was typically less than the difference from 12 o'clock to 1 o'clock (30 degrees)....that is the entire range for the valve to be in spec. So then I was aiming for a 12:30 slot position (~15 degrees) and locking it down. Check, re-check, torque, check, re-check, repeat if needed. Watch the adjustment screw slot position as you tighten or torque the lock nut and if it moves, most likely have to start over.

-As much as I would like to extend my valve checks I just cannot justify it. Not because I'm paranoid that the valves are suddenly going to be grossly out of spec, but because of all the other maintenance items that can be performed in conjunction with the valve checks. I'm talking about the fuel hose, coolant hoses, breather/air hose, and electrical cable inspections that need to be looked at under the gas tank & surrounding the throttle bodies. I've seen 1 fuel hose rub that needed protection, 2 cable/wiring runs that needed better routing or relief, 1 air hose rubbed nearly 1/2 way thru, oil leaks, coolant drips, etc... Every time I do the valve checks, another potential problem is discovered. Your results may vary.
 
Joined
Dec 21, 2012
Messages
499
Location
Corinth, TX
Bike
2013 Yamaha FJR1300
Yamaha interval is 26K for many of their bikes.
FJR interval is 26K miles. One of the FJR forums did a survey of high mileage FJR's and about half needed no adjustment at 52K and a third needed no adjustment at 78 K. Don't know if the third were contained in the half at 52 K.

I am guessing that things have come a long way in the past 50 years.
 

Woodaddict

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Jan 2, 2012
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894
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64
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Salisbury,NC
2024 Mileage
005726
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Red NT700V & Spyder RTL
just did another valve check(6-5-2015), or Honda dealership did it. this interval was 38,013 miles, from 69,027 to 107,040. last post about my valve check was #20. intake or exhaust gaps were in spec or just out by .001. still good for engine over 100K. mechanic said engine still sounds good. now I'm ready for my trip out west!
 

Phil Tarman

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Dec 12, 2010
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81
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Greeley, CO
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2010 Silver NT700VA (ABS)
I've gone 22,000 miles since my last adjustment. I'm thinking I'll see if I can get Chuck Henderson to coach me through doing it before I go to Montana in August. I'll probably put another 1500-2000 miles on before then.

Or, I might just wait until after I do the Working on the Railroad Rally in Montana in August. That would only add another 3-4,000 miles depending on how I come home.
 
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