XRAY - Model racing cars

Hello guys, I apologize in advance for my English is not perfect, and I hope you understand my problem anyway.
When the ruler of the shock absorber rebound, following the manual (by unscrewing the bottom cap and slowly pumping the damper shaft, 10 times for a rebound of 75%, 15 times for the rebound to 50% and 20 times for the rebound to 25% ) if I try to set the rebound to 50%, I never get to do a chore and I come to 50, and often following strokes, such as 15 strokes, I am often rebound to 25 %.... you like make the rebound?
it is normal for me is that so?

PS: in the shock body, use an oil to 200
PS2: It is normal that menbrane shock after I disassembled to shock only 2 times, these have become larger, and then I struggle to place them correctly on the lip of the shock?

Forgive me again for my English;
I thank in advance all those who respond
Best Regards
Stefano

but the difficulty of setting the rebound may depend on the membrane that has grown?

yes
but 2 sets of those menbranes and put those new and everything should be fine

Hi

I assume you are referring to the plastic shocks....

350 - 450 cSt oil is typical for carpet.
The new shallow shock membranes (308081) work well and are easy to bleed
I tend to run low/no rebound on carpet, 50% rebound on asphalt
I have drilled the shock top with a 1mm hole into the bladder cavity to reduce rebound

My method to bleed and set rebound on plastic shocks is as follows:
1. Fill with oil to the top
2. SLOWLY pump the piston to get the air bubbles out from under the piston
3. Slide the membrane onto the oil surface, and hold with your finger
4. Carefully slide a small cable tie end (or screwdriver blade) between the membrane and the shock body. This will release excess oil from the shock body
5. Fit the shock top and cap
6. Check the rebound (often this will be correct already)
7. If not, extend the shock fully, and hold upside down, loosen the bottom cap
8. Firmly "tap" the end of the shock shaft with your finger a few times. DO NOT pump or pull on the shaft as it will pull air into the shock body.
[You are trying to squeeze the (thick) shock oil out of quite small clearances between shaft and body, a slow push just deforms the membrane at the top, and does not create enough pressure inside to force the fluid out of the bottom. A "pull" on the shaft creates a partial vacuum inside the shock, and (thin) air can get in really easily]
9. Recheck rebound
10. Repeat 7-9 as necessary - only a few repeat cycles are needed (2-3)

Hope this helps

I agree with Stanley that 200 is too soft. You must follow the manual directions and make sure that the shock absorber must be at upside down possition and then loosing the bottom cap to set the rebound.