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Old 15-03-2009
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RogerM RogerM is offline
*SuPeRsTaR mEmBeR*
 
Join Date: Oct 2007
Location: The middle of off-road nowhere ----- Cheltenham
Posts: 4,258
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Quote:
Originally Posted by Fabs View Post
Is it too late to say I did it on purpose?
Fabs, feel free to tell everybody that you did it on purpose, I think it was an inspired decission!

Here is my reasoning .......

I ran the SP all last year (from Oct 07 actually) and NEVER broke a rear shock tower even though I was using the alloy tower mounts. Since I've gone to the FS I've broken a rear tower at every track I've been to, at first I thought it was just Coventry's big double jump but I broke one at Kiddy too, and a few other places including an indoor track!

Here is what I think is happening. With the shocks mounted to the front of the rear tower they dig in if the car turns over and due to the canterlever effect of the shock being spaced off the tower excerts a large bending moment on the tower which has no choice but to fail at the change in section for the mount recess.
Due to the amazing quality of Kyosho's mouldings the towers survive to let you finish the run, just with a car that feels a little reluctant to change direction towards the opposite side to the breakage as the tower flexes. You can feel when the tower has cracked but at least you CAN finish the run.

By mounting the shocks on the rear of the tower the rounded edge of the moulding is all that contacts the ground and that doesn't dig in like the shock cap does thus doesn't load the tower in the same way so it survives to fight another day.


To prove this point I took the car to a local BMX track and deliberately threw the car off the jumps badly and sure enough after a couple of minutes I cracked a tower. Fitted the new tower and mounted the shocks on the back of the tower & wishbones and no matter what I did I couldn't break a tower!!! Ok I've wrecked both wing mounts, a front tower and a wishbone testing this out but if I have found a way of keeping the car in one piece for a full season of normal use without having to replace any major parts as was the case last year with the SP I'm happy.
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