501X/DB01R dampers
 

Hi,

I just built my new DB01R buggy and for the first time i built dampers without a cap (diaphragma) at the top of the cylinder. :blush: The manual says you have to fill oil until 1mm to the top. I rated that or is there a simple way to measure that? When taking too much oil it seems the piston isn´t able to fully compensate and if you fill in not enough and fully press the piston it sounds as if there are air bubbles inside.
Did i build something wrong? Any help would be much appreciated. I have been building many many dampers over the years but never without a cap.

Thanks in advance!

They are are supposed to have air in them as they are aeration dampers.

James

I fill the shocks until they are totally full - put the cap on loosely, not quite fully tight - then slooooooooooly push the shaft in to let out excess juices.
Nip the cap tight and make sure the shaft will fully compress / check the rebound and make sure all the shocks are similar.

I use these in all my TrF dampers http://www.stellamodels.net/catalog/...oducts_id=2427

I bought the dampers seperately as the "TRF buggy dampers" and also did the 1mm on sight.
The thing is they supply small hex screws you can screw into the shock caps. But nowhere in the manual it specifies to do this or why one would do this.

Figured out later this is to be able to bleed the shocks from excess damper oil.

I imagine having more or less air will affect a certain characteristic of the damper behavement but i'm not really sure how.

Maybe someone can shed a light on the inner workings of the aeration damper?

I use the bleed screws. Just drill a hole from the inside of the cap to open the bleed hole.
http://www.oople.com/rc/photos/review501x/shocks01.jpg

I fill the cylinder until they are full.
Put the cap on tight.
Push the shaft in slowly.
Tighten the bleed screw.
I think it works just fine.

Thanks for all your answers. Does it mean i first drill in a hole in the cap, the fill the damper completely full and then put the cap on, fully push the piston so that the oil which is too much can come out of the hole and then screws the blled screw in? Is that correct?
If i don´t use the bleed screw method the secret is to fill the completely full?

this is on another thread but here is how I do it:-

I have not drilled out the hole for the bleed screw, i set the dampers without doing that.

i fill the dampers 2/3 then slowly raise the piston allowing the trapped air to escape while making sure the piston does not break the surface of the oil.
when all the air has escaped i then fill the damper cylinder to the top. the oil at the top should look concave.
pull the piston all the back down.
top up cylinder if necerssary.
screw cap on.
hold the threaded portion of the piston and push all the way up to your fingers.
when you let go the piston should come back half way down by itself.
damper set.
easy.

hope this helps

I have done it this way for over 20 years and never had a problem.
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Thanks for your detailed description Super Gripper. I will try it this way.

So Jimmy bleeds all the air out through the bleed valve, and Supper Gripper leaves air inside. What is the difference on the track? When would either setup be used?

Sounds interesting... i think also Super Gripper tries not to have air inside. It may be more difficult to exactly get the right amount of oil in the cylinder to not have air inside but also not have too much oil inside which leads to the need of more power to compress the piston...this is what i found out so far.

Thanks. Would you say that is about 50% rebound? Does that mean the piston gets progressively harder to push in the further you go down? When would this be desirable?