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Valve clearance

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Rocker66
29 minutes ago, Andy m said:

Swings and roundabouts as always. The drain plug thread is worn by the change (alloy thread with a steel plug is poor and many are stripped by garage monkeys) and there is a period where the oil pump primes. At some low number of miles you are doing more harm than good. Then there is a range where you are just wasting oil and damaging the environment. Then there is a correct period, then one where the engine is wearing more than it needs because the oil is worn out. All oil analysis I've ever seen from fleets suggest the manufacturers never risk getting close to the wear zone. The only bike data I've seen was for a Weestrom in the US. The Suzuki interval at 4000 was in the waste/environmental damage zone. 12000 was a safe interval. 

 

All screw threads faced with vibration turn so I can believe shims are better. I have no proof and would suspect the difference is so marginal you may as well have the ease of screw threads. Faced with screws I know I can finish the job the same day. Faced with shims, I face having to order parts, giving the dealer another advantage. 

 

I have seen sparkplug failures. I suspect these are such cost sensitive item that you are changing them in case you have one that is wearing quickly. 

 

I will change my oil at the Honda interval so I can stamp the book and tick a box for the salesman who will be expected to make me an offer on it in 30 months/20000 miles. If the engine sounds fine the valves will be left alone as "longevity" is not my problem. 

 

Andy

 

 

You do what you like with your bike and I will do what I want with mine. More frequent oil changes give me peace of mind and that’s what I’m going to stick with . In all the years I have done (or had done) oil changes I have never had a problem with the drain plug.

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SteveThackery
32 minutes ago, Andy m said:

 

All screw threads faced with vibration turn.........

 

 

Bit of a sweeping statement there.  Especially when the screw threads are locked by a nut.  Any evidence for us?

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Andy m

20+ years experience of trucks, busses and trailers. Wheel nuts (also moving both parts) are a disaster area after the EU banned our left handed ones for one side, others variously undo to varying degrees, I would guess depending on the frequencies of vibration they see. There is of course a huge difference between a 17-inch wheel (small ones are worse) Barnes Wallacing across the A1 and a valve adjuster 1 Nm out after a million miles, but get rid of the thread and it can't fail that way. You would think adjusters would be easier for production too, surely having assembled (or at least paired the cam and other bits) it would be easier to just keep going rather than working out and fitting a shim? 

 

Rocker, you can indeed do what you like. You are though wasting your money (again your choice) and using resources that will then not be available to others in the future. "I've always done it and I'm happy" is I doubt entirely correct. You used to change oil more often before multigrades, de-coked the head due to poor petrol and inefficient combustion, used leaded 4-star to kill people's brain cells and a host of other things we now are pretty sure aren't as good as they might be. 

 

Andy

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Rocker66
43 minutes ago, Andy m said:

20+ years experience of trucks, busses and trailers. Wheel nuts (also moving both parts) are a disaster area after the EU banned our left handed ones for one side, others variously undo to varying degrees, I would guess depending on the frequencies of vibration they see. There is of course a huge difference between a 17-inch wheel (small ones are worse) Barnes Wallacing across the A1 and a valve adjuster 1 Nm out after a million miles, but get rid of the thread and it can't fail that way. You would think adjusters would be easier for production too, surely having assembled (or at least paired the cam and other bits) it would be easier to just keep going rather than working out and fitting a shim? 

 

Rocker, you can indeed do what you like. You are though wasting your money (again your choice) and using resources that will then not be available to others in the future. "I've always done it and I'm happy" is I doubt entirely correct. You used to change oil more often before multigrades, de-coked the head due to poor petrol and inefficient combustion, used leaded 4-star to kill people's brain cells and a host of other things we now are pretty sure aren't as good as they might be. 

 

Andy

The number of empty wagons I see parked up on the A2 and A20 waiting to go to the port and tunnel each one probably using more resources in a month than I will in a life time.

I don’t drive a gas guzzling car or fly off to foreign parts on highly fuel inefficient and highly polluting planes so I think that my local motorcycle trips and once maybe twice a year oil changes are seriously depleting the world’s oil resources.

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suffolk58

Just bringing it back to the original thread a bit......

I've just got the bike back from the 32,000 mile service. Valves checked and no adjustment needed. In fact they said that of all the NC range they've serviced over the years, only twice have the valves needed adjustment.

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SteveThackery
2 hours ago, Andy m said:

There is of course a huge difference between a 17-inch wheel (small ones are worse) Barnes Wallacing across the A1 and a valve adjuster 1 Nm out after a million miles, but get rid of the thread and it can't fail that way.

 

Ah, so you are softening your sweeping statement a bit.  That's fair enough. 

 

FWIW, I think there are zillions of threaded fasteners that never work loose (or "turn", as you put it) in service, even when subject to vibration.  You need to specify the intensity and frequency spectrum of the vibration in order to determine how much energy it can deliver to the fastener, and whether that is enough to overcome the static friction.  Given powerful enough vibration, it must theoretically be possible to overcome the friction in any threaded joint and loosen it - I'm sure we agree on that.  But if the vibration is below a critical threshold for that threaded fastener I would argue that it won't ever come loose or turn.  The design engineer is responsible for determining how tight a fastener must be to remain secure in service.

 

I'll tell you this: I've never, not once, found the locknut on a valve clearance adjuster loose, so I don't believe they can move or unscrew in service if torqued up correctly.

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pilninggas

Something i like about the NC is the ease of valve adjustment. I've done on a 20-valve bucket and shim yamaha and it took bloody hours. The NC was just over an hour with a coolant swap too. I dont know why anyone would skip it.

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SteveThackery
5 hours ago, SteveThackery said:

 

I'll tell you this: I've never, not once, found the locknut on a valve clearance adjuster loose, so I don't believe they can move or unscrew in service if torqued up correctly.

 

Despite what I've said, I still wonder what's going on if it's really true that screw-adjusters require more frequent adjustment than shim types.  

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Graham NZ

Maybe the contact surfaces differences between screw tip  and valve, and cam lobe (or rocker) and bucket or shim which accounts for a faster wear rate on the screw tip.

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Andy m

Shims seem to be designed to rotate (so can present a fresh face to the cam/follower/rocker) and as simple components can be hardened? Screw adjusters always seem to be "hardware" items so possibly not? A jungle/dealer bodge with shims can be to turn them over. The worn face no longer facing the same way can sit differently on some designs. 

 

Comparison is difficult. The ones I had to adjust frequently (Enfield iron barrel, Ural, Guzzi) are stone age technology and poor materials. The ones I did enough miles on for a serious comparison (BMW R1100 and 790 Bonneville) seem to be similar needing it doing after 20+ thousand miles, so hardly a trip killer. I don't recall ever adjusting the same valve twice. The BMW was better because it was a certain one day job where as there was a risk Triumph wouldn't hold the shim you needed in a location you could get to. 

 

The best solution of course is hydraulic. You have to buy a Harley or Enfield UCE though. Valve adjuster type isn't a huge factor in me buying a bike though. 

 

I have helped do the demonic valves on a Ducati. Two shims per valve, the circlip from hell and set of fork things required to hold it. I was glad to be mostly making tea. It took 4 days from riding in to riding out including two trips out for shims. It came in sounding like a bag of spanners and went out the same. Less than 10000 on the clock after 4 years use, but the main purpose was a few miles at twice the speed limit and the adulation of fellow riders, something it achieved. The owner came to worry about reliability (been there, done that) and moved on to a Kawasaki.

 

Andy

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SteveThackery
2 hours ago, Graham NZ said:

Maybe the contact surfaces differences between screw tip  and valve, and cam lobe (or rocker) and bucket or shim which accounts for a faster wear rate on the screw tip.

 

Yes, I was wondering that myself.  The pressure is greater if the force is concentrated at a screw tip, I would have thought.

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SteveThackery
47 minutes ago, Andy m said:

 

The best solution of course is hydraulic. You have to buy a Harley or Enfield UCE though. Valve adjuster type isn't a huge factor in me buying a bike though. 

 

 

Which brings another mystery to mind: how it is that the hydraulic lifters on the Enfield make the most appalling din; far worse than correctly set manual adjusters on its predecessor.  

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Andy m

The oil pump design is still based on the 1930's circuit. I suspect at idle the pressure is a bit low for the hydraulics. If its designed to work that way it's fine. They don't seem to break (or maybe it's just con rods that beat them to it!). 

 

Andy

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SteveThackery
14 minutes ago, Andy m said:

The oil pump design is still based on the 1930's circuit.

 

Eh??  I thought it was completely different?  The oil pump is a trochoid instead of piston type, it's in a different place, it shifts eight times the volume, the feed to the head is internal, and it lubes the primary drive and the gearbox as well (they had their own oil baths on the original).  Every part of the engine is different from the original British design - not a single common component.  The hydraulic lifters shouldn't need a high pressure feed as they pump themselves up (in theory!) - but perhaps they aren't getting a consistent, air-less feed.

 

I've noticed that the tappet din is independent of engine speed (or rather, it varies slightly, but apparently randomly, and is just as bad at all speeds).

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Andy m

If its not a legacy thing, why does the oil level still drop so much on a running engine? The sump is shallow and the window a daft idea, but it just never seemed to work like any other engine except the Iron barrel. When cold or hot there was a performance difference just as you had on the iron barrels, much more severe than say an XBR or XT. As you say, if air gets in but can't get out, they've managed to find a new way to make it clattery!

 

I am very much of the school of thought that earplugs and reference to speedo vs throttle position tell me if its supposed to do that. Once warm the UCE seemed to do its job to me.

 

Andy

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Graham NZ

My dear old Buell with it's HD based engine has hydraulic tappets.  It is a noisy engine mechanically, possibly partly because of those tappets but it's also full of roller and ball bearings.

 

Recently as I was adjusting tappets, changing coolant and servicing the chain on my NC I realised than the Buell needs none of those tasks.

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klrman
On 15/09/2018 at 21:07, Graham NZ said:

My dear old Buell with it's HD based engine has hydraulic tappets.  It is a noisy engine mechanically, possibly partly because of those tappets but it's also full of roller and ball bearings.

 

Recently as I was adjusting tappets, changing coolant and servicing the chain on my NC I realised than the Buell needs none of those tasks.

Yep, no adjustment on belts. Just a lot of inconvenience, lost time, expensive recovery and if I accurately recall what my mate told me when either his Fire bolt or his Cyclone ( I don't know which) bust last Thursday, a fairly hefty replacement bill involving taking the back end apart. No rivets, split links or "O" rings here.

 

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Mr Toad
11 hours ago, klrman said:

Yep, no adjustment on belts. Just a lot of inconvenience, lost time, expensive recovery and if I accurately recall what my mate told me when either his Fire bolt or his Cyclone ( I don't know which) bust last Thursday, a fairly hefty replacement bill involving taking the back end apart. No rivets, split links or "O" rings here.

 

 

One of my friends had a belt break on his HD while on holiday in Germany, it took three days to get a belt to the nearest dealers and get it replaced. Of course he was moaning and complaining about it until it was pointed out that he'd been told by HD at one of the services that the belt was ready for replacing and hadn't because he was too tight.

 

I'm assuming this was down to some damage or maybe excessive wear caused by poor cleaning as most HDs never need a belt and many manage 70-100k plus on the original and are still going.

 

Does your mate inspect his belt regularly for damage? Or has he checked it a couple of times then forgotten about it, an easy thing to do and missed some damage?

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klrman
26 minutes ago, Mr Toad said:

 

One of my friends had a belt break on his HD while on holiday in Germany, it took three days to get a belt to the nearest dealers and get it replaced. Of course he was moaning and complaining about it until it was pointed out that he'd been told by HD at one of the services that the belt was ready for replacing and hadn't because he was too tight.

 

 

 

Does your mate inspect his belt regularly for damage? Or has he checked it a couple of times then forgotten about it, an easy thing to do and missed some damage?

Replaced with recommended Buell parts 13000 miles ago. Inspected regularly  and cherished. 

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Graham NZ
22 hours ago, klrman said:

Yep, no adjustment on belts. Just a lot of inconvenience, lost time, expensive recovery and if I accurately recall what my mate told me when either his Fire bolt or his Cyclone ( I don't know which) bust last Thursday, a fairly hefty replacement bill involving taking the back end apart. No rivets, split links or "O" rings here.

 

 

On a Buell the belt does not require the swing arm to be removed.  I changed the belt at 70,000km but didn't need to. The cost was about $390 NZ, or about the same as a chain and sprocket change. A recommended mod is to fit a Free Spirits spring loaded belt tensioner, which I did when new.  I frequently ride on gravel roads without a problem.

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baben
On 9/14/2018 at 17:35, SteveThackery said:

 

Ah, so you are softening your sweeping statement a bit.  That's fair enough. 

 

FWIW, I think there are zillions of threaded fasteners that never work loose (or "turn", as you put it) in service, even when subject to vibration.  You need to specify the intensity and frequency spectrum of the vibration in order to determine how much energy it can deliver to the fastener, and whether that is enough to overcome the static friction.  Given powerful enough vibration, it must theoretically be possible to overcome the friction in any threaded joint and loosen it - I'm sure we agree on that.  But if the vibration is below a critical threshold for that threaded fastener I would argue that it won't ever come loose or turn.  The design engineer is responsible for determining how tight a fastener must be to remain secure in service.

 

I'll tell you this: I've never, not once, found the locknut on a valve clearance adjuster loose, so I don't believe they can move or unscrew in service if torqued up correctly.

Both the bolts on my side stand on my BMW F800ST worked loose - one fell off and the other was on its way when I spotted it.

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