Hi
I have recently received my dampers back from Simon @ Cornering Force in Yorks.
I have had several phone conversations with him, mithering him with questions and understanding what happens and what to expect.
For background, he is a very knowledgeable chap and is involved in the Amd Golf which raced in the BTCC this year
For reference, here is a before and after of my dampers.
Before
After
As you can see, they have been powder coated + anodised after being shot blasted to tidy them up first.
This is at a cost of £65 per side but not essential but worth it in my opinion considering they now have a pretty thick protection layer to prevent the build up of crap on them which occurred previously.
They have been de-pinned at a cost of £20 per side and have had the Schrader valve replaced on each one at a cost of £4.50 per side.
It seems Renault loctite in both the pinning mechanism and the schrader valve for good measure.
On their return, I spoke to Simon regarding the 'default' number of 'clicks' they have been set at to see if they are as standard as I was considering playing with them on a few trackdays.
The answer was 22 and 18 which surprised me.
It is common for dampers like this to have different settings on the adjuster to achieve the same amount of damping and rebounce each side due to the tolerances in the valve. Simon believes this is also the case for the new units from Renault as they are definitely pinned manually as the pin is in varying position and rarely straight - hence awkward removal of grub screw by some people !
Bearing this in mind, it is also impossible to harden or soften the damping rate evenly without putting them on a dyno to test.
For eg, with mine at 22 and 18 to achieve the same rate, adding 3 'clicks' on each side will give different levels once adjusted. This has completely put me off wanting to adjust them at all whenever I do my next trackday as I will never be sure (and therefore confident) to put them back to standard again.
The adjustment (unless both side happen to give the same damping on the same settings) will never be linear when being adjusted - food for thought !
Simon also has talked about general usage and the ability to repressurise the gas chamber if required.
Under standard usage, the shaft should have a very small amount of oil weeping out onto it. This is due to the gas pushing against oil but the o-ring against the shaft stopping it. If the o-ring is failing then too much oil will leak out, and if the gas has failed completely (as had happened in one of mine) then no oil is being pushed out and a black wear mark was visible on the shaft where the o-ring was being worn out prematurely.
At the bottom of the unit is the Shrader valve. This used to pressurise the gas chamber. It seems Renault fill this with loctite to prevent usage..... On refurbed units, this replaced with a functional valve again.
The refurbed units are pressurised to 65 psi using nitrogen. If they are suspected of failing, they can be repressurised using air and a standard mountain bike damper pump which can be bought for around £20.
65 psi is the target but the gas pressure is not entirely responsible for the damping rate so it dropping does not directly effect the damper performance. Only a very low pressure or complete failure is critical.
All of this information has been received from Simon Roberts from Cornering Force in North Yorkshire http://www.corneringforce.com/
I have recently received my dampers back from Simon @ Cornering Force in Yorks.
I have had several phone conversations with him, mithering him with questions and understanding what happens and what to expect.
For background, he is a very knowledgeable chap and is involved in the Amd Golf which raced in the BTCC this year
For reference, here is a before and after of my dampers.
Before
After
As you can see, they have been powder coated + anodised after being shot blasted to tidy them up first.
This is at a cost of £65 per side but not essential but worth it in my opinion considering they now have a pretty thick protection layer to prevent the build up of crap on them which occurred previously.
They have been de-pinned at a cost of £20 per side and have had the Schrader valve replaced on each one at a cost of £4.50 per side.
It seems Renault loctite in both the pinning mechanism and the schrader valve for good measure.
On their return, I spoke to Simon regarding the 'default' number of 'clicks' they have been set at to see if they are as standard as I was considering playing with them on a few trackdays.
The answer was 22 and 18 which surprised me.
It is common for dampers like this to have different settings on the adjuster to achieve the same amount of damping and rebounce each side due to the tolerances in the valve. Simon believes this is also the case for the new units from Renault as they are definitely pinned manually as the pin is in varying position and rarely straight - hence awkward removal of grub screw by some people !
Bearing this in mind, it is also impossible to harden or soften the damping rate evenly without putting them on a dyno to test.
For eg, with mine at 22 and 18 to achieve the same rate, adding 3 'clicks' on each side will give different levels once adjusted. This has completely put me off wanting to adjust them at all whenever I do my next trackday as I will never be sure (and therefore confident) to put them back to standard again.
The adjustment (unless both side happen to give the same damping on the same settings) will never be linear when being adjusted - food for thought !
Simon also has talked about general usage and the ability to repressurise the gas chamber if required.
Under standard usage, the shaft should have a very small amount of oil weeping out onto it. This is due to the gas pushing against oil but the o-ring against the shaft stopping it. If the o-ring is failing then too much oil will leak out, and if the gas has failed completely (as had happened in one of mine) then no oil is being pushed out and a black wear mark was visible on the shaft where the o-ring was being worn out prematurely.
At the bottom of the unit is the Shrader valve. This used to pressurise the gas chamber. It seems Renault fill this with loctite to prevent usage..... On refurbed units, this replaced with a functional valve again.
The refurbed units are pressurised to 65 psi using nitrogen. If they are suspected of failing, they can be repressurised using air and a standard mountain bike damper pump which can be bought for around £20.
65 psi is the target but the gas pressure is not entirely responsible for the damping rate so it dropping does not directly effect the damper performance. Only a very low pressure or complete failure is critical.
All of this information has been received from Simon Roberts from Cornering Force in North Yorkshire http://www.corneringforce.com/
