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Adjusting the valves on my XS400


johnsnownw
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Does anyone know if I need a torque wrench for the screws on the alternator cover? I got a quote of $178 to do the adjustment, and if all I need to do is buy a torque wrench and feeler gauges to do it myself, I would gladly make an attempt.

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Does anyone know if I need a torque wrench for the screws on the alternator cover? I got a quote of $178 to do the adjustment, and if all I need to do is buy a torque wrench and feeler gauges to do it myself, I would gladly make an attempt.

you don't really need a torque wrench for the screw although it only 6lbs ft so don't go mad!!

do it yourself its really easy if a little fiddly, try and buy the angled gauges as they can be manovered easily.

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you don't really need a torque wrench for the screw although it only 6lbs ft so don't go mad!!

do it yourself its really easy if a little fiddly, try and buy the angled gauges as they can be manovered easily.

Thanks Drewps.

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let us know how it goes and take pictures too if you can.

im gonna have to be doing this soon as well. :P

Can do, hope to have it done by this weekend.

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Right, so I attempted to adjust my valves today. It did not go as planned. I think I have the exhaust valves properly adjusted, however the intake valves make even more noise than before. I only had the straight feeler gauges which didn't help much with the angle I was using. I couldn't get the bent ones for the intake, but had them for the exhaust. So, I think I've just loosened the intakes a bit too much. However, I also changed the oil, and I'm not sure if that would have an effect or not.

Does my current situation ring a bell with anyone? Did I just loosen the intakes too much, and that's why the valves are louder?

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Right, so I attempted to adjust my valves today. It did not go as planned. I think I have the exhaust valves properly adjusted, however the intake valves make even more noise than before. I only had the straight feeler gauges which didn't help much with the angle I was using. I couldn't get the bent ones for the intake, but had them for the exhaust. So, I think I've just loosened the intakes a bit too much. However, I also changed the oil, and I'm not sure if that would have an effect or not.

Does my current situation ring a bell with anyone? Did I just loosen the intakes too much, and that's why the valves are louder?

Changing oil shouldn't make the valves noisier...assuming, of course, you've got enough oil in the crankcase! Adjusting valves is a bit tricky...kinda a pain in the rear, actually! There's suppose to be a "slight drag" on the feeler gauge when clearance is correct...but just how much is a "slight drag"??!! If the feeler gauge is pulled at a slight angle, it'll affect the drag! And tightening the lock nut may change the clearance! Might help to have three gauges...one at minimum clearance, one at max, and one at median clearance (there's usually a range of settings...like .004-.006). These will act as a go/no go check. You can make your own "angle feeler gauges"...just bend the straight ones!

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Changing oil shouldn't make the valves noisier...assuming, of course, you've got enough oil in the crankcase! Adjusting valves is a bit tricky...kinda a pain in the rear, actually! There's suppose to be a "slight drag" on the feeler gauge when clearance is correct...but just how much is a "slight drag"??!! If the feeler gauge is pulled at a slight angle, it'll affect the drag! And tightening the lock nut may change the clearance! Might help to have three gauges...one at minimum clearance, one at max, and one at median clearance (there's usually a range of settings...like .004-.006). These will act as a go/no go check. You can make your own "angle feeler gauges"...just bend the straight ones!

Wish I could bend them, the intakes are from .003-.005. The .003 and .004 gauges that I have seem far to flimsy to bend. I can't tell you how distraught I feel at the moment, I just cannot believe that I didn't adjust them correctly...I checked and re-checked them.

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you can bend them a bit at the tips.

I always set them to the smallest gap and feel a slight drag.

BTW the things are noisy anyway so don't expect quiet, these are an aircooled 30 year old bike pre noise restrictions so don't be too hard on yourself.

mine do make a clatter and that was after full rebuild with new parts!

it all adds character to the bike ;)

the valve gaps are for timing not noise prevention

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The only feelers I was able to get, aside from the straight ones, are both at the lowest gauge. So, I suppose I'll try setting it to the lowest one.

Just got to wait for the bike to cool down, shouldn't take too long as I only had the bike running for 3-4 minutes.

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Well, I went a readjusted them, the right side was spot on, but the left was a tad bit loose. Now they are all in spec, but the valves are a bit louder. I had to re-adjust the carbs, and noticed that no matter how far in or out I turned the mixture screws I couldn't get the carbs to race. So I just settled with what appears to be a slightly rich mixture, but the bike idles and revs quite well. Not sure why the carbs are acting differently, but still seems to work alright.

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Well carb changes aside, it is running fantastic. Took it our for a bit of a ride, when the rain stopped, and she runs just beautifully. No hesitation anywhere, and she sounds a lot more like a motorcycle now. The exhaust is just deeper and throatier. The bike feels like it might have a little more pep as well, but might all be in my head. Just couldn't be more pleased at the moment.

So, now I guess I can turn it over to my fiance...can't say I'm that pleased to do so.

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