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1mm thickness rubber sim insertion between rear inner rubber bush and trailing arm supporting bracket was performed on VW1302 Super Beetle as mentioned before yesterday. 4 donut shape sheets were prepared, with 54-30 sized , for insertion at outer and inner portion promptly and inserted and re-tightened. It took me 3 hours for me to do that, because the long nut prepared 19mm for Hex hinge bolt loosening was not adapted, the size was adjusted into 16mm by hand grinding. The procedure was not so difficult but the time was required to make up a special tool was so, though Hex bolts on trans-axle as oil plugs were 19mm. Applied 1mm thickness rubber sim on outer and inner sides of original inner trailing arm bush has eliminated too much compliance and hysteresis phenomena as imagined. As the results, all the bad steering habit has eliminated, but stiffness of steering centric position, linearity of transition and astringency were obtained in stead. As a matter of fact, push up phenomena has increased but acceptable and hidden right side running habit came out again. Now the suspension and axle construction has become good for precise wheel alignment adjustment, I have to do that soon.
This kind of trifle experiment was so effective to change an automobile charactor into better condition, this is why I keep making efforts on the experiments onto 1/1 mechanical model like a Beetle. Now my VW1302 Super Beetle has re-acquired the ultimate performance as designed that cannot be done on another Beetle models with Swning Arm axle desig.

I want to limit the lateral movement of IRS in VW 1302 Super Beetle, because the displacement of rear axle construction while steering action does affect on the function at the initial rising stage so much. Dull and muddy reaction should be eliminated if the astringency of the steering response, otherwise the advantage of light weight 850kg could not be taken some advantage as a passenger's car that is very rare now. Refreshing, gloating and cleverer riding taste could not be obtained until the escapement of steering power input should be closed everywhere of axle construction, so the lateral arm inner bush deformation behavior would be changed as a experimental attempt today. This kind of reversible modifications could be permitted for an enthusiastic amateur like me, because the condition could be set again as it was without any destruction, if it turned into worse result. I'm sure the steering action would be far improved after the experiment judging from my deposited experiences. I'm going to measure the size of inserting thin rubber sims from now today. I have 9 hours from now before the Ashiya Symphony Regular Concert begins at Fukushima Osaka.

Got out I for test driving of SXE10 TOYOTA Altezza after the thrust angle adjustment, as the frontal alignments had been established few days ago. Only 0,60mm external movement of rear toe adjusting linkage rod eliminated the chronic wondering disease thoroughly. As for my surprise, almost I was about to make a rear-end collision on the highway, becoming very sleepy especially if the conditions are overlap, a vehicle with good wheel alignment and after lunch. It's often the case that a well aligned automobile induces sleep, because the reduction frequency on steering adjustment while cruising leads to distraction of concentration.
I wanna put an emphasis on this point that the only disadvantage of establishing the precise wheel alignment is "Induction of Sleep!". We cannot be too careful not to fall into "Sleep" while driving an automobile specially well adjusted one.

Instability on steering reaction of VW1302 Super Beetle has been caused by just a trifle factor, lower tire pressure according to atmospheric lower temperature, 0,2kg/cm2. We have fore seasons with 30 degree temp. differences. It's a matter for being ashamed that I didn't realize the fact immediately in spite of long term experiences with poor sensitivity.
Spent I afternoon yesterday for rear brake shoe adjustment and clutch wire lubrication, both of them are very important to enjoy smooth and comfortable ride, with not two stepping pedal reaction but solid and tight pedal touching and well controllable clutch and pressure plate meeting and engaging without any unnatural wire slipping resistor.

Thanks to this misunderstandings, I could check out the construction of rear trailing arm inner bush mounting construction, a huge Hex headed bolt from diagonally forward direction outside is used as hinge centric fixing pin and axial pressure is exerted by a metal solid washer is utilized. So, it is relatively easy to control the rate of compliance in lateral direction by inserting adjuster sim made of metal or rubber material between bracket and rubber bush external surface imbedded in the lower suspension arm inner hinge. 1mm thickness sim on both inner and outer side would perform the resisting power preventing the movement of the arm in axial direction. The reduction of compliance on this portion would be effective on the stability in exchange for some increase of deterioration of ride, also here occurs as usual.

The improvement of steering reaction at rising stage should be felt so considerably as to fix steering centric position while straight running, this is the result of killing a dead zone of steering performance. I would re-realize that the rear axial compliance has much to do with the rising stage of steering action, so imagine I do. Additionally, the change of the reaction is on the exponential curve, so it would not be so difficult to find out the most suitable rate of compliance for applying the adjusting sim as an experimental trial. This kind of interesting play should be done as an usual manners among the research and development division of every manufacture.
I'm sure that too much compliance applied VW 1302 Super Beetle would graduate from dull and muddy steering action and born again into a different automobile just like a young fish released into some clear stream.
The procedure and the result of this experiment on the rate of rear arm compliance change would be reported here very soon and the easiest way to recover and re-obtain an original or better steering reaction without replacing bush parts here, if the rubber material inside had not been destroyed physically.

A backlash on drug rink and on rear trailing arm brings instability while straight running of VW 1302 Super Beetle, for the former problem, the parts had been replaced but with ignorable bad adaptation with too much clearance and for latter one, a professional engineer says that the replacement of related bushes is one of the indispensable task to be performed, because of 40 years interval after production. Wondering bad habit occurs and it needs some concentration to keep straight running. So, careful checking and experiments are the next work for me to be done as soon as possible.
The performance of steering action is far inferior to BC7 that had been well serviced on the compliance application of mechanical steering constructive designing also lateral displacement of rear axle. No tight corner locking phenomena on BC7 was observed this morning, recovered on this mechanical dysfunction on rear transfer clutch problem?