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Valve Adjustment

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How often is it needed to be checked. I have heard on here many times that people have checked them and they were in spec. My bike has about 1000+ miles. Runs like a raped ape. Should I have them checked anyway? I would rather stay on the side of caution. Any thoughts.

ThankX in advance

Paul

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The initial check is the most important so I would check them as soon as practical. I checked mine for the first time around 1000 miles. My exhaust were in spec as was my left intake. My right intake was a little loose at .008. A little loose is ok but you want to avoid being tight as this could cause some damage. The book gives you a service schedule as far as frequency of checking. It also depends on how you ride. If you are one of these guys thats always on the rev limiter you had better check them often. If you ride sane then the book schedule will work just fine.

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Good advice Falcon, it is better to check them often and for them to be fine then replace a bunch of expensive parts because you don't want to spend the hour to do it.

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A little loose is ok but you want to avoid being tight as this could cause some damage. QUOTE]

What type of damage may occur?

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As the valve clearance tightens you eventually reach the point where the valve does not close all the way. When this occurs hot gases from combustion leak through the valve and seat area leading to damage (burnt valve) of the valve and seat. Honda allows a tolerance of plus or minus .001 for both intake and exhaust valves. If your clearance is more than .001 on the tight side I would re-shim before the next ride.

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As the valve clearance tightens you eventually reach the point where the valve does not close all the way. When this occurs hot gases from combustion leak through the valve and seat area leading to damage (burnt valve) of the valve and seat. .

Ohh you mean tight on the cam and loose on the seat. I thought you meant loose on the cam which would mean tight on the seat. Here is a picture of a loose seat/tight cam sineriao. You can see that the right intake,the bottm left one in the picture, is stretched out to its max. IT dudnt result in a burnt valve but was well on its way. Burnt valves are pretty rare on the intake side but can happen. if this was an exhaust valve it probably would have over heated.

IMG_0147.JPG

Honda allows a tolerance of plus or minus .001 for both intake and exhaust valves. If your clearance is more than .001 on the tight side I would re-shim before the next ride.

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You are correct. Intake valves live a much happier life. They usually run cooler than the exhaust valves as they enjoy cool air and fuel flowing over them. Regarding tight or loose, it always refers to what you find with your feeler gage between the cam lobe and the valve mechanism. Sorry for the confusion.

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I just checked my valves for the first time last night. My X has 700 miles on it. Contrary to all the hype, all of my valves are in spec and almost dead on I might add.

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At 70 hours mine were still all in spec.

Read the directions carefully, you shoul dhave a light drag on both sides of the feeler gauge. Doug

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I checked mine for the first time yesterday, the intakes were a little loose, the 6 guage slipped in and out easily, don't have a 7 but the 8 wouldn't go in. The exhausts seemed to be a little tight, the 11 went in but was tighter than I would expect, the 10 felt about right. The decompressor was right at 14.

I have 220 miles on the bike, decided to leave them alone and check again at 600 miles - thoughts?

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After I rode with a (Husa)berg rider recently who was using a valve saver additive in his fuel with positive results I decided to call Honda's technical call centre (in Australia mind you) who agreed that whilst the 450X's weren't experiencing valve clearance problems in general, the extra protection afforded by a valve saver additive couldn't hurt. My bike is just 5 days old but I will be running the valve saver in the fuel all the same. At just 10ml / 10 litres it is cheap insurance.

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using a valve saver additive in his fuel with positive results
I've never heard of valve saver - who makes it? What is it?

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I've never heard of valve saver - who makes it? What is it?

There are many "valve saver" additive products on the market Down Under. But then we are told our fuel here is pretty poor by world standards so maybe you don't have the need / market for it in the US. I can't remember who makes the "Valve Saver" brand but Nulon (among other manufacturers) makes a competitve product. It's a liquid fuel additive that in simple terms "put's the lead back in unleaded fuel", raises RON, and protects valves / seats from wear. Not that the products have any lead in them at all, they are a concentrate chemical. :thumbsup:

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