BW35 gearbox Pressure gauge thread

My point is that the constant radius section of the cam is indicated on the attached picture between the red lines arrowed in green. This is a very large included angle and I could set it anywhere within the red lines and be in accordance with the manual. The cable is not overly slack in any position, but I imagine that difference in cam position will have a large effect on the gear changes? As I get clunky downshifts and it seems to hold on the the gears, I think that the cable is over rotating the can and so I need to shorten the outer. This will make the cable more slack but 'taking out all the slack' in the cable is hardly an engineering specific operation!!
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Having had another think, I am beginning to realise why most people use the test drive method!! So I now understand that the valve has to rest on the constant radius section of the cam. The exact location is not relevant though as this is dictated by setting the closed throttle position so that the cable has no slack. This is where it gets a little woolly though. The cam takes so little force to rotate that the cable never really tensions up so seems to have slack in it even when operating the cam. The cable is relatively stiff so this is no surprise! What is does mean though is that there is no distinct setting point when setting by the cam really. So what I do know is that my original setting was such that with no slack to mention, the pressure when tested with a gauge, rises very sharply to well over manual requirements. This is because the cam has a very steep initial ramp and also explains why the tolerance for pressure settings is so wide. So my plan now is to slacken the cable off and refit and fill the gearbox and then use the gauge again. It is actually the only proper way to get the setting right as far as I can see!!
 
I have eventually got my sump back on, no oil leaks, fluid level correct, and made an attempt to set up the kickdown cable with a pressure gauge. The original reading was around 60PSI at tick over but jumping to 140PSI when the revs were increased to 700rpm in D. The pressure jump was fast, almost as soon as I touched the throttle, however this is not surprising as the cam operated by the cable in the gearbox has a very steep ramp right at the start of its travel. According to the manual it should be between 90PSI and 105PSI at 1000rpm in D. I started to screw the adjuster inwards on the throttle link end. Eventually the pressure started to drop. I can only get it down to around 115-120PSI at 1000RPM though as I have run out of adjustment on the cable! I took it for a test drive and the difference in gearchanges was amazing. I can hardly feel any changes at all now. I can just feel a slight bump when going from 2nd to 3rd but only when you lift off the throttle to force it to change. Otherwise it is perfect.

I would really like to get the reading down a little lower to where it should be but I am not sure how I can achieve that without modifying the cable and I am not keen to try. As the improvement is so great I am probably best leaving it alone!!
 
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