XRAY - Model racing cars

I've heard people are using a membrane behind the bladder. Some are using O-rings as well. What is the part number for the o-ring ? What do you guys recommend on this ? What to use and how many ? How much rebound do you like ? What is your shock building technique including bleeding and so on ? I should mention that I'm racing Stock and Mod on carpet with Jaco foam tires on a FK. Tonyv, Andreas or anyone your help would be appreciated. Thanks Again.

Xray offers the #308090 - Shock Foam Inserts (4) more info you can find here at

Thanks Brano. Does no one have any advice ?

Dalton thanks for the great info. I don't trust any of the shops around my house. They are lucky to find the car parts. Nevermind find a o-ring. I had the o-ring thing suggested to me and wanted to hear what others thought. I will familiarize myself with your procedure and let you know how it turns out. I can't wait for RCA to get there kits so my dist. can get there's. This waiting is killing me. The first race series might be over and I still don't have a car. I'm looking very much to racing this car.

Hi Chris,

Rebound is a nice fine tuning option that a lot of people doesn't us.
There is no thruth when you should us it. I think that you should test for your self and driving. But I will give you my preferences anyway.

For asphalt racing, I always use rebound. I do test some different rebound though for different asphalt and layout. But in generall, less grip more rebound.

Indoors, rubber tires, on tight tracks with high grip I use no rebound.
Open tracks, high grip, medium rebound
Low grip medium, to high rebound.

Indoor, foam. The conditions that I have the least knowledge and testing from. I would however use medium bouns for starting setting. I think that this is what Cyrul,Burch and Groskamp used succesfully a couple of times.

To make the rebound, I use the xray shock foam insert that Brano wrote about. I also sometime us a mini-Z spring ( hard and medium ).
I never us O rings anymore. I tried this but never found it better that the above. Also the O-ring will cause the bladder to break more easily.

Hope this helps abit

Best regards
Andreas Myrberg

So more and quicker rebound is a good thing ?
Thanks.

I never thought about using rebound as a adjustment tool. You never stop learning I guess. This might work in 1/8 buggy as well.