Well now with 33k on the clock I can't be sure when the last adjustment/check was so thinking its long overdue just wondering if it's best going down a DIY route never done this adjustment before.. Anybody able to say which way to go either dealer or DIY? Been looking into it and found this http://www.tlzone.net/forums/performance-enhancement/130134-how-adjust-tappet-valve-clearances.html
Have a bash at it yourself. It's a bit of a ballache DIY but if you have a guide/Haynes/workshop manual then there's usually nothing difficult other than simply following the order of doing things. I did mine on the Ninja and yes it took a while but then it was the first time I'd done it and was learning as I went
It's pretty straight forward, with some knowledge. Make sure you have a good torque wrench, make sure you have the valve clearances right before removing the cams, make sure you rotate the engine in is normal direction to take up backlash in the gears. If you go too far round wind back past the marks and then turn back with engine rotation. Check the clearances twice, turning the cams between each check. Inlets can be a bit tighter as they run cooler, exhaust an bit loose as they run hotter (so close up more), remember this when you work out the new shims. If the exhausts are above the mid point (wider) this will be fine. In comparison inlets can be below mid point (tighter).
Presumeably the clearances only increase, which will only mean more noise and minimal drop in performance! Heard once that clearances can decrease, How! does anyone Know?
First time is always a time consuming one, as you have to measure the clearances ( I always check 2-3 times, going through the whole set each time so that any settling / error on one reading is eliminated). Once you have done that it looks easy enough getting the cams out to check the shim sizes. Best with a micrometer to check as often the shim sizes aren't actually stamped on or have worn away. Note the shim size, then work out what size you need. If the clearance is too small, you need a smaller shim (drops the cam bucket away from the lobe). If the clearance is too large, a bigger shim to lift the bucket closer to the cam lobe. Always worth checking all of them, even if they don't need doing now so you have the data for the future. How do you ride - and is there a setting or a tolerance range for the clearance? If you are always using top end revs and power, set the clearances to the tight end of the range, if you normally use more bottom end / mid range set them at the upper end as you pick up midrange and torque. See if you can swap shims between valvesw - you may have one which needs to go wider, one which needs to go tighter - they may swap shims. Google the shim diameter - auto stores can often supply a matching shim size for a car at a fraction the cost of a bike shim. If I remember rightly my Triumph triple has 4 Toyota valve shims in, costing less for the 4 than one OE Triumph shim.... Once you've done all the adjustments, double check twice that the clearances are now correct. Better while everything is still off than once you've put it back together and it doesn't run right, or worse! Don't rush it, be methodical, keep it clean. Use a sucker not a magnet to remove the buckets - a magnet will magnetise the bucket and cause it to hold on to any ferrous fragments in the oil - not good.
Have a go hun...i'm sure you can do it ..i watched Ian do his a few months ago ...just write down the numbers
Yep, usually caused by valve regression. This is when the valve seat or valve wear through various reasons. As valves rotate in the seat any debris entering can act as a grinding paste on the surfaces. The effect is to close the valve clearances. That's why you should always use an air filter. Aggressive fuels can also cause regression ie, gas from waste. Miss match of materials is another. In extreme circumstances the valves can stretch at the head (overheating) causing the head to dish.
Well at least you dont have to buy a shim tool.for the XJR its about £60 from Yamaha,sometimes owners club do a shim swap or they are about £5 each should you need any,I got a mate to do mine as i had never done them before my bike needed 2 so not to bad
Like I say, try an auto store. Somewhere that does trade counter and proper, not Halfords. be a LOT cheaper than a full shim kit. And probably quicker. If you ever have to do the valves on a cam removal engine that doesn't use gears like yours but a chain drive to the cam sprockets, you can often avoid cam timing issues by cable tying the chain tightly to the sprockets before taking the cam out. As long as you keep it taut and it doesn't drop out of engagement at the bottom it makes life a lot easier.
The change in clearance is mostly down to wear between the valve seat in the head and the seating area of the valvfe itself. So the valve creeps slowly towards the cam lobe as the clearance reduces. So waiting for them to get noisy as it widens is a bad idea. Different engines and styles of usage will wear at different rates, so affecting when they will need adjusting.
Just measured all the old tappets and only 1 out of 4 on the front cyl measures what it says all others are at least 0.5mm off?? Usual or not?
Slack according to micrometer.. my calcs all 4 need swapping too (Front cyl) Will recheck and measure em again first though
