CR01 damper/suspension problem.
 

Hello all.

I am new to RC, and this is the first time i assembled a kit.

As far as i know, i did everything right and the CR01 is running smooth. However, i have a couple of problems. The torque twist is too much, so much that the corresponding wheel goes up in the air when i accelerate.

second, the dampers compress but do not rebound. so the whole car appears slumped down and not like the ones i have seen so far.

on doing some research, i have zip-tied mod and removed the front (gold) sway bar but that has not helped the damper problem.

please help me with it.

thanks.
http://img707.imageshack.us/img707/9039/75660699.jpg
http://img210.imageshack.us/img210/3646/67679021.jpg

Looks normal to me. These trucks tend to sit in the middle of their range of motion. That gives them some up and down travel, like a real truck. You could install stiffer springs to gain some ride height.

Install a firm spring in the right rear or put a thicker stabilizer bar between the rear suspension. The twist will always be there but it should be minimized.

Mine doesn't ever lift the front tire unless I'm on the steepest of climbs or if I'm trying to peg the throttle on flat ground. But I only have the medium barrel springs in back and hard barrel springs in front with a thin bar up front and medium in the rear.

so in its normal position, if i press it down, it should rebound up as i let go, right?

the problem is only with the front. once i press it down, it doesn't bounce back whatsoever. i have to pull it back.

how do i fix that?

maybe rebuild your shocks? What springs do you have up front? Maybe they don't have enough strength to lift the weight of the chassis and battery back up

i have the designated springs up front, the ones mentioned in the manual.

im concerned about the damper oil weight. i think i have filled them too much. how do i rectify that?

is there any after-market oil that i can use for the CR01 dampers?

are the dampers suppose to rebound? i was under the impression that when they are depressed they don't return to their position, is that not the springs job. correct me if i am wrong, please.

They should have a little push back.

You can use any damper oil in them, not just Tamiya. They should also have no air bubbles in the oil. The only air should be on the backside of the little red diaphram

since im new to this, any recommendation on what oil should i get?

i would start with something around 30wt, but changing the oil will only make it rebound either slower or faster. and if you overfilled the shocks with oil the shock would slightly try to hold the front down

Sounds like you've got the wrong oil in the shocks, or you've got some binding going on in the suspension. If you disconnect the shocks from the cantilevers, what happens?

factory shocks
 

i use the 2 hole disc for the shocks they rebound and drop pretty good. There is upgrade shocks that seem to travel up and down smoother.

Hummmm, I've been running mine for quite a while now and haven't had any problem like this. I know that the stock shocks are pretty cheap ass and mine have leaked fliud ever since I first put them on it. I'm sure they and pretty low on fliud at this point but I just haven't felt like messing with it yet because it still works fine to me.
Your problem might be in how you built your cantilivers. I'd take your shocks off the truck and then push the suspension down and see if it rebounds any. Do the elimination process and check each suspension componet one at a time. Also, a correctly filled shock should rebound slowly just a little when you compress it all the way.

Torque twist is a given on the CR01. You can minimise it (as explained already) but it won't go away.

To build some rebound in the shocks you need to close them with the piston at the bottom of travel and add a small foam disc under the cap so the diafragm won't move up. You might need some testing though to find which piston works best for your needs/style. Kit oil is fine.

The sway bar is meant to help you, put it back. A stronger spring on the rear LEFT (not right as mentioned above) will help reducing torque twist, but again, it won't cure it. Load the wheels with lead (as much as you can) and that'll help again.

I run no springs on my shocks except for the rear left, no sway bars either and about 250grams of lead in each wheel, 85T motor. Still have to fight a little bit of twist but absolutely minimal.

Droop is much more useful than clearance. The car being a short wheelbase, you won't have problems getting hung very often and when trying to climb a step/ledge, you want the car as close as possible to the ground, not up in the air to tumble backwards. Besides, if your wheels droop under their own weight then at least when you are hung on a rock, your wheels will touch the ground and hopefully get some traction to pull you out. No need to clear the rocks by five centimeters only to have the wheels up in the air as soon as you hit a bump. Remember, this is CRAWLING, i.e. like a reptile, belly dragging on the ground.

Thank you for all the helpful replies guys. This forum is a life saver. I am thinking of buying stiffer springs and aluminium dampers. Any suggestions on where i could get them?

I am gonna take my CR-01 apart and put it back together with more love and patience than i did before and will get everything right.

Any suggestions on the pistons to use for the front and the rear dampers (two hole, three hole)? Tamiya gave multiple types with the kit.

thanks for all the help once again.

Get the Losi shocks but keep in mind the balljoints will need the screws slightly sanded down to go through as the holes are imperial size (just under 3mm dia).

got a part #? i've had it with these leaking shocks, worst part is i i get the oil rainbow in the water i run through, not cool.
thanks.