Damper bump and rebound

[AndyLotus]

Hi all,
A while ago I sent my old Protech dampers back to the factory to un seize the adjuster and re- build them. They told me they were too far gone, which they probably were, and could offer a big discount on a new pair. Fair enough.

The thing is I find I cant get the setting correct. At first wound fully tight they were still too soft so I indexed the adjuster round to the next stage. (3 stages, each with 12 clicks I think)

What I'm finding though is that if I try and bounce a rear quarter it barely moves (I'm 15 stone so not light!), however when driving it still seems like it's too soft in rebound. Over undulations yesterday I banged my head on the roof

Would someone mind trying to bounce the rear quarter of their cars to see how soft they are please? Something just doesn't seem right with the balance between bump and rebound.

Thanks,
Andy.

[Hawaiis0]

I'm an afternoon away from getting my new Protechs fitting finished and getting the car off sticks.

I'll post my findings later

Stu

[AndyLotus]

Thanks for that.

Crack on then

[richardw]

Something's definitely not right. I have used Protechs for the last 3 years without this problem. From memory fronts are on 9 or 11 clicks and rears on about 6 which gives a great ride/handling compromise. What I have found is that on just one click too much the suspension feels uncomfortably stiff, and one click too few it feels mushy , so it is easy to tell if you've got it right.

I believe SJ - who supply the dampers - have an exclusive agreement with Protech so I wonder if you have been given the right setup?

Cheers, Richard

[AndyLotus]

Hi Richard,

Thanks for the info.
I'm thinking I might have to send them back to Protech to check the specification.

Would you say that if you push down on the rear it moves with the pressure? I just checked mine again and it really barely moves at all at the back.

There's always something to keep one busy

[CHRISYD]

Ive only got standard 4 year old rear dampers but ive just bounced the rear and it hardly moved either. from memory my old excel had protechs all round that sj fitted and they set them at half way all round and that didn't bounce much either.

[AndyLotus]

That's interesting, I always kind of assumed that it should be a bit 'Lotus' soft.

Maybe I have more of a problem with just rebound being incorrect.

[Hawaiis0]

My rears are set 2 clicks from the right . Tried a few rough roads and a couple of humpback bridges, all in all settled very quickly nothing untoward. No undulations with my 13 stones. Slight pull to one side but that was due to a 17psi tyre

[richardw]

Agree with others - mine doesn't move down much with pressure at the back.

Richard

[AndyLotus]

Thanks chaps.
I think I may give Protech a call on Monday (if they are working) and see what they say.
Cheers.

[DavidOliver]

Andy, when you contact Protech ask them for the bump and rebound rates at each click, and the recommended Excel rate front and back.
Then you can have the dampers set up by a local specialist with the gear to measure damper rates.
Or perhaps Steve at SJS can tell you/us.

Ah! Then you can tell us all what the recommended settings are, adjusting for our personal weight of course.

Dave the cog.

[AndyLotus]

I'll do my best....

[Pete Boole]

The single biggest problem with most aftermarket dampers is too much compression damping. When the dampers feel OK in compression they're usually under-damped in rebound - that's why it often seems so hard to find the "correct" setting.

Pete

[AndyLotus]

That's exactly my thinking. I guess they can tailor them to how you want them and I think a little more rebound relative to bump would improve things.

[Pete Boole]

The bump/rebound characteristics are built into the damper design. Changing the setting on the valve (turning the knob) does not significantly alter this.

Pete