Thanks for the explanation
The part on the rocker arms is extremely helpful. It confirms what I thought about the distribution of the forces to the damper. I will definetley try out several rocker arms and types of geometry to get it to work well.
The regulations are just something I have to accept - running rear tires might now be necessary (or optimal for that matter), but on the other hand, if the project turns out to be (extremely) succesful, lighter wheels and/or inserts could be developed for it too.
Quote:
Originally Posted by terry.sc
The double wishbone suspension is fine, it's one less variable to deal with for you. The long trailing arms used on the old cars would help reduce rear weight, but you have to get the geometry right first time or come up with some way of adjusting the wheel hub on the trailing arm. The double wishbone setup you have will be much simpler to adjust.
At national level races we usually have a rule that means you must use a particular tyre on the rear of the buggy, both on 2wd and 4wd classes. It's not that you have to use rear tyres on the rear, it's just to save the racers having to buy lots of tyres just in case one particular spike or compound works better than the rest on that particular day, so saving money as you know in advance what tyres to buy. If everyone uses the same tyre then there is one less variable, usually the tyre is chosen by the local racers so you can guarantee it works well. There is no limit on what tyres you fit on the front so you can choose which front tyres give the best balance for you, having only one type of rear tyre also means you only need 2-3 different front tyres to choose from, again saving money.
With rocker arms, if the shock and link mounting points on the rocker are the same distance from the pivot, the spring rate will be the same as the shock compresses the same amount as if it was mounted on the wishbone at the same angle. As your links are angled quite low, if your shocks were mounted there instead you would need stiffer springs than normal.
If your shock is mounted on the rocker at 2 times the distance from the pivot as the link mounting point, if the link rises 3mm the shock will be compressed 6mm, and you will have 2 times the spring rate pushing on the link.
The only way to be sure you have it sorted is to experiment. The X11 has machined rockers as the geometry was already developed from the original Predators, and TTech themselves didn't get it right first time which is why we had the GP rockers, which were the original plastic rockers with a carbon fibre plate on top to move the link mount to a different angle on the rocker. You can always do the same if needed, make the rocker a bit smaller and use a carbon fibre plate to attach the link or shock mounts to the rocker, so you can easily cut and drill new plates if you need to change the rocker geometry.
If you
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