stiscooby

Does anyone know if this suspension has to be "refurbished" after a period of time?

Going to look at a car which has these fitted (Tein Super Street) and just wondered if it's something that will ever need to be done?

Cheers

bren@apex

iTrader: (20)

The suspension only needs addressing if it develops a fault. The only periodic maintenance that you might want to do is to free up the locking collars, regrease and grease the top mount bearing to prevent it seizing. The dampers themselves dont need refreshing unless they actually fail.

jgevers

A damper is a hydraulic valve that converts energy into heat (well over 100 degrees Celcius in some cases). This heat is absorbed by the damper oil. This oil does degrade and puts down deposits on the shims. Hence, dampers should be serviced every now and again. And I am not even talking about wear on internal seals that start allowing oil to bypass the shim stacks and the damper to lose efficiency.

On cheap coil overs you might not notice this so much because there is that much stiction to start with that blurs the actual damping :-)

Mind you, I have only been working on dampers in motorsport for 20 years, so I could well be wrong....................

bren@apex

iTrader: (20)

Sorry, I didnt realise we were talking about £3k motorsport dampers on a race car that need constant maintenance due to the high wear rates on internal components that are designed for minimum stiction over longevity. Oh, hang on, we arent, were talking about cheapy Tein Super Streets on a road car.

If you go to the extent of having the dampers stripped and rebuilt periodically then youd be better off throwing them in the bin and buying new, the costs are on a par. Hence the advice I gave.

jgevers

I was talking about dampers as hydraulic valves, not about expensive motorsport dampers per se. In any case, these expensive dampers have a much LOWER wear rate than most cheap coil overs due to lower stiction (read friction) and better manufacturing tolerances. The reason for frequent rebuilding dampers in motorsport is change of damping rate due to use (it is still a hydraulic valve after all, that changes with use) and preventative maintenance.

You are right though that the cost of rebuilding dampers can be higher that replacement.

But I was talking from a technical perspective, not from a cost, sales or marketing perspective.

jgevers

I normally have difficulty in assessing if a damper has failed, especially for a road car. Some failures can be seen easily e.g., leaking (not weeping) top seal or bent rod/spindle etc.. But efficiency loss, internal tube wear etc. are much harder.

Most good damper manufacturers have rebuild and replacement policies based on hours of use (high end motorsport manufacturers) or mileage (road car damper manufacturers). I suppose that is because dampers are critical safety equipment that ensure correct contact of tyre to road surface and a damper with low efficiency or incorrect damping curve will drastically increase braking distances, reduce grip/traction and negatively influence handling.

Some cheap dampers that have appeared on the market, made by 'me too' far eastern manufacturers with nice websites and factories but no real credentials in damper development, are leaving themselves wide open to legal challenges in case of accidents and failures. A lot of these use 'generic stacks' for all vehicles and spring rates and allthough they might feel ok on a car initially, could provide very unpredictable results in some situations.

Again, these are only my opinions as a suspension engineer that has been involved in damper design, development and manufacturing for most types of vehicle use.

bren@apex

iTrader: (20)

stiscooby was asking about Tein Super Street. I wouldnt spend money on periodic overhauls on cheap steet dampers when its uneconomically viable to do so and the clever move would be to sell them and start again if and when a problem arises. Hence my advice.

jgevers

:-)

bootneck

Nobody likes a smart ****. Get back in your box :-)

jgevers

Lid firmly closed.........