Koni Refurb Workshops - South of England?

[Knightrider 1]

Bought a used Koni SSk Sport kit (Vogtland springs and Koni adjustable dampers) the other day for £150. I feel like a right git as I didn't notice that one of the fronts had been leaking oil, only spotted it when I got them home and dismantled to clean them up before fitting. I believe that they can be refurbished. Anyone know who can do this well and for sensible money? Any recommendations?

I'm in Sussex, so somewhere not too far would be good, so I can drive there rather than post.

[Knightrider 1]

Hello? No-one any ideas?

[Knightrider 1]

Answering my own question having done some research - because I thought it might help members.

Paul Drake, Raceline Suspension in Newbury. Gave me plenty of time and advice on the phone.

Really helpful and very knowledgeable bloke.

He re-valves shocks for folk who are racing cars to provide the ride/damping they need/want and can advise.

KONI specialist but can refurb almost any make, including coilies, except Bilstein.

There is a 4 digit code on KONIs stamped into the casing that tells you the date manufatured. Mine is 0302, so despite the guy I bought them from telling me they were '2 years old' they are in fact week 3 2002, so Jan 2002 and are 8 years old.

Does that matter (as I faintly shit myself) I ask Paul? No it doesn't, Paul tells me as he is refurbing KONIs from 1961. They are endlesly fixable, so age and mileage don't matter really - they are either leaking and not working properly or working fine.

He is going to charge me about £45 to fix mine, new one is about £150, so that is a bargain.

You don't need to get them refurbed in pairs - I asked the question. As my other front one is fine, no leaks, I can just get the leaking one fixed.

Only problem that makes it too expensive to refurb is if the piston rod is scored, bent or damaged. Mine doesn't appear to be, so fingers crossed.

Hope that is useful to peeps out there.

[finny 0]

Good info KR.

I have a used set (not yet fitted) and the stamped 2997. So assume kit is week 29 and from 1997!

To be fair, the guy who sold the kit to you may have brought it 2 years ago from a shop that had it in stock since 2002.

Mine aren't leaking, however there is no hardly any resistance/ damping to the front struts. I can push the piston down quite easily (might have it on its lowest setting) and it comes up slowly aswell. Is this right?

Looks like the eibach springs are going to do all the work.

I think I'll need them overhauled as I'm sure when I fitted nearly new (standard) dampers & springs, the damper at least had some resistance/ damping forces.

Might have to give your chap a call soon.

[grafteratwork 2]

One off mine are leaking to just were adjust it 45 pound sounds good to me

[Knightrider 1]

I think mine have been 'in use' for about 8 years. The bottom of the strut has lost most of it's paint and is quite rusty. The bloke I bought them from bought them from someone else, so I think he just invented '2 years old'!! Still, don't think it matters.

My front (the non leaking one) is really easy to push down. The adjustment seems to mainly affect the return or rebound. On soft, it returns to full extension quite fast. When I set to full hard, it doesn't and you have to pull it like crazy and even then it returns really slowly - return goes like a rock, but no apparent difference to compression.

So Finny, yes I think that is right.

[Knightrider 1]

Right, done more research! Too much time on my hands, clearly (which is actually true!).

The adjustment on Konis is only on the rebound, not the 'bump' or compresion stroke.

I've found a really interesting couple of long blogs by a US guy who is a damper guru. Raced Jap stuff, but did a load of research. I'm going to post it separately, but here are the two links. Unless you read the linked stuff, some of the terminology in this summary doesn't mean much (for example, the shim stack, but all becomes clear when you read the blogs - shim stacks are key!!!):

http://farnorthracing.com/autocross_secrets6.html

http://farnorthracing.com/autocross_secrets18.html

It is REALLY technical, but worth a read. The totally scary thing is how variable even new dampers are out of the box, especially on rebound, and how irregular the adjustment can be - clicks version or Koni smooth turn version.

Here is a lift from the website:

Amazingly, save those brands mentioned in that earlier list, this was a non-stop parade of horror, including, but not limited to:

1. Adjusters that did absolutely nothing;

2. Adjusters that had more crosstalk effect than they had primary effect (ie, a rebound adjuster where 1 click made a 10% change in rebound and a 30% change in compression);

3. Adjusters that were nonlinear and exponential;

4. Adjusters that peaked in the middle of the adjustment range (in one example, "full hard" was softer than "full soft");

5. Shimstacks assembled upside-down;

6. Sets of shocks where a front and rear shimstack had been exchanged;

7. Shocks valved with forces that were insane (1600 lbs/in @ 3 in/sec was the record);

8. Shocks that faded so fast (as they warmed up) that no two runs were ever alike;

9. Shocks with adjusters that varied by 10% on the same shock at the same setting, depending on if you got there by going harder or softer; and

10. Shocks that adjusted rebound and compression in lockstep, but had so much compression that backing them down to reasonable levels made rebound way too soft (very common with the Japanese brands like GAB, JIC, Tein, etc)

Back to Paul Drake in Newbury - he does have a damper dyno, I've asked him. So he can check whether a pair of dampers a) are really 'matched' with respect to bump and rebound and how the adjustment works relative to each damper.

Read the stuff from the guy in the US. Doesn't make you feel too good.....but Konis seem to do better than most!!

Even though only one of my fronts needs fixing, I'm going to send him both, despite the extra expense, so I can know a) are they matched on bump and rebound and how variable are they in terms of rebound adjustment. He doesn't charge really for putting them on the dyno.

Incidentally, all you coilie peeps, exactly the same applies.

Hope this is useful - sorry, another long post from Knightrider, but I do think a lot of members struggle with some of the technicalities with suspension/dampers which are after all critical to improving our lovely motors and cost loads. Maybe they would quite like to be better 'informed'. So if there are sites from which they can really learn about how stuff works, upsides, pitfalls and so on, should be useful. Yes/no?