Here are a few things I decided to document from my last maintenance session. Hopefully some of it will prove helpful. I don't intend to defend or debate any of it - it is simply how I do it.
I use 10W-30 Amsoil motorcycle oil. There are lots of good motorcycle oils, so I am not selling anything here. I do believe that 10W-30 is a better choice than 10W-40 for this bike in almost all weather situations. Some folks think that heavier oils give better protection, but what really matters is what weight the engine has been designed for. When a range is given, I run the light end of the range because the cold start-up lubrication is better and that is where lots of wear occurs. On a very high miles engine, I might use the heavier end of the range.
There are lots of good filters and more than a few bad ones as well. You can save yourself the worry of the specifics (like anti-drainback valves, bypass pressure, etc.) by sticking with the Honda OEM filter. I use those, but I also use Purolator and Amsoil filters. This is the Purolator PL14610. It is a bit longer than the stock filter but fits well enough behind the awesome Hondabikepro bash plate...
I do valve adjustments at 10,000 miles. I have no basis for that other than it seems to work. For simplicity, all of my machines (cars and bikes) get a minor service at 5,000 miles and a major service at 10,000 miles. Most of the BMW's spec a 6,000 service interval and the Honda specs an 8,000 mile interval, so I am inside of both of them with my intervals. I am sure that the specified intervals are fine, but I like to be able to look at the odometer on any of them and know what's coming up.
With the NC, the first step of valve adjustment is to get the radiator out of the way. I take the opportunity to clean it inside and out and also to completely refresh the coolant. I always use fresh washers. This is the 90463-ML7-000 washer for the coolant drain plug on the block. The service manual does not spec the torque, so I use 72 inch-lbs (repeat INCH) for 6mm steel hex bolts in aluminum threads. I don't think anyone's feel is as accurate as a good calibrated torque wrench.
You are in here anyway, why not remove and clean the overflow container? I see no sense in not taking the time to clean what you remove before it goes back on...
When removing a radiator, reaching up in here to try to release the clips on the airbox drain and left spark plug wire as well as the electrical connector for the fan, is a bit tedious.
When I don't feel like messing with it (usually) I just take off the three bolts that hold the fan to the radiator and remove the radiator with that stuff still attached to the motorcycle...
Then after I have washed the radiator inside and out, I reinstall the fan onto the radiator. It is not so hard to reattach the stuff as it is to remove it.
Be sure to empty the drain hose for the airbox while you have easy access. There is usually not much there, but some oil carries over from the crankcase ventilation system.
When adjusting the valves, I DO NOT remove the cam timing inspection plug. It is not easy to access and the torque by degree process is something to avoid. I can see why Honda gives this method as it will work in all cases - even if the rockers and cams have been removed, but on a normal valve adjustment none of that has happened. So, I leave it alone.
Instead, I locate T1 and check for some clearance on the exhaust valves. If there is no clearance, I rotate the crankshaft counter-clockwise 360 degrees to T1 again and check for valve clearance. If I have some (any) clearance on at least one exhaust valve and one intake valve, then I am at the correct timing location.
There has been a lot of discussion about whether it "hurts" to spin an engine backwards. Whether it "hurts" or not, it is not recommended and I do not do it. The manual says "counter-clockwise" in all mentions of manually rotating the engine. Please start your own thread if you wish to refute this. When you turn the crank bolt, it helps to use a breaker bar instead of a ratchet. You should have the spark plugs out when you do this, and at a certain point in the engine rotation it will fall forward on the weight of the crankshaft counterweights. When the ratchet over-runs, you will lose your place in counting degrees of rotation. With a breaker bar, even if the crank follows through, the breaker bar handle will still be indexed with your turn. Once you have set the #1 (left) cylinder's valves, you need only move 270 degrees more to line up T2 for the #2 (right) cylinder.
When you reinstall the caps, Honda specs grease on the threads and oil on the o-rings. The torque spec is "very damned little" - 10Nm on the smaller inspection port and 15 Nm on the crank bolt port.
GENERAL NOTE: Don't confuse units between Nm and Ft-lb. If a torque is given in newton-meters and you mistakenly set the number in your torque wrench as ft-lbs., you will apply 35% too much torque to the fastener sometimes with very bad results. Also make sure that the stated thread conditions are adhered to. Examples: dry, oiled, anti-siezed, greased, with thread sealer, etc.
I use 10W-30 Amsoil motorcycle oil. There are lots of good motorcycle oils, so I am not selling anything here. I do believe that 10W-30 is a better choice than 10W-40 for this bike in almost all weather situations. Some folks think that heavier oils give better protection, but what really matters is what weight the engine has been designed for. When a range is given, I run the light end of the range because the cold start-up lubrication is better and that is where lots of wear occurs. On a very high miles engine, I might use the heavier end of the range.
There are lots of good filters and more than a few bad ones as well. You can save yourself the worry of the specifics (like anti-drainback valves, bypass pressure, etc.) by sticking with the Honda OEM filter. I use those, but I also use Purolator and Amsoil filters. This is the Purolator PL14610. It is a bit longer than the stock filter but fits well enough behind the awesome Hondabikepro bash plate...
I do valve adjustments at 10,000 miles. I have no basis for that other than it seems to work. For simplicity, all of my machines (cars and bikes) get a minor service at 5,000 miles and a major service at 10,000 miles. Most of the BMW's spec a 6,000 service interval and the Honda specs an 8,000 mile interval, so I am inside of both of them with my intervals. I am sure that the specified intervals are fine, but I like to be able to look at the odometer on any of them and know what's coming up.
With the NC, the first step of valve adjustment is to get the radiator out of the way. I take the opportunity to clean it inside and out and also to completely refresh the coolant. I always use fresh washers. This is the 90463-ML7-000 washer for the coolant drain plug on the block. The service manual does not spec the torque, so I use 72 inch-lbs (repeat INCH) for 6mm steel hex bolts in aluminum threads. I don't think anyone's feel is as accurate as a good calibrated torque wrench.
You are in here anyway, why not remove and clean the overflow container? I see no sense in not taking the time to clean what you remove before it goes back on...
When removing a radiator, reaching up in here to try to release the clips on the airbox drain and left spark plug wire as well as the electrical connector for the fan, is a bit tedious.
When I don't feel like messing with it (usually) I just take off the three bolts that hold the fan to the radiator and remove the radiator with that stuff still attached to the motorcycle...
Then after I have washed the radiator inside and out, I reinstall the fan onto the radiator. It is not so hard to reattach the stuff as it is to remove it.
Be sure to empty the drain hose for the airbox while you have easy access. There is usually not much there, but some oil carries over from the crankcase ventilation system.
When adjusting the valves, I DO NOT remove the cam timing inspection plug. It is not easy to access and the torque by degree process is something to avoid. I can see why Honda gives this method as it will work in all cases - even if the rockers and cams have been removed, but on a normal valve adjustment none of that has happened. So, I leave it alone.
Instead, I locate T1 and check for some clearance on the exhaust valves. If there is no clearance, I rotate the crankshaft counter-clockwise 360 degrees to T1 again and check for valve clearance. If I have some (any) clearance on at least one exhaust valve and one intake valve, then I am at the correct timing location.
There has been a lot of discussion about whether it "hurts" to spin an engine backwards. Whether it "hurts" or not, it is not recommended and I do not do it. The manual says "counter-clockwise" in all mentions of manually rotating the engine. Please start your own thread if you wish to refute this. When you turn the crank bolt, it helps to use a breaker bar instead of a ratchet. You should have the spark plugs out when you do this, and at a certain point in the engine rotation it will fall forward on the weight of the crankshaft counterweights. When the ratchet over-runs, you will lose your place in counting degrees of rotation. With a breaker bar, even if the crank follows through, the breaker bar handle will still be indexed with your turn. Once you have set the #1 (left) cylinder's valves, you need only move 270 degrees more to line up T2 for the #2 (right) cylinder.
When you reinstall the caps, Honda specs grease on the threads and oil on the o-rings. The torque spec is "very damned little" - 10Nm on the smaller inspection port and 15 Nm on the crank bolt port.
GENERAL NOTE: Don't confuse units between Nm and Ft-lb. If a torque is given in newton-meters and you mistakenly set the number in your torque wrench as ft-lbs., you will apply 35% too much torque to the fastener sometimes with very bad results. Also make sure that the stated thread conditions are adhered to. Examples: dry, oiled, anti-siezed, greased, with thread sealer, etc.
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