Koni Rear Dampers

[Gary Flinn]

Hi all

 

My first time on the new Forum, I'm after some advice.

 

I'm in the Process of trying to fit Koni Rear Telescopic Dampers in place of the Lever Arm dampers on my Mk2 Vitesse?

 

I have purchased the usual Top Extension brackets and got some Koni 80-1717 Shocks which are the correct open & closed length for the Mk2 Rotoflex suspension (These are actually for a lowered early Mini, but I have been advised by several people on the Club Triumph site are correct for the Mk2 Suspension) I have gone for Koni to match the front of my car and they have a good reputation for quality. 

 

I was supplied with the Top Extension Brackets, the special 5/8" Diameter Sleeved Bolts with 1/2" UNF Threads at the end to fix the top of new Telescopic Dampers to the bracket, these sleeved bolts are similar to the original type bolts for fixing the top of the Telescopic Dampers to the Chassis bracket.

 

However I have got problems with the original Koni 80-1717 Damper Bushes being too Small and narrow to suit the width of the new shock bracket, also the 80-1717 bushes have 3/8" holes in the bushes but the Bolts I have are sleeved to 5/8" diameter where they go through the Damper bush?

 

The Original Herald/Vitesse damper bushes are two part and are too big for the 80-1717 Damper Eyes and are also the wrong shape so I cannot use these?

 

The original Koni 80-1717 bushes have a central metal sleeve with a 3/8" diameter bolt hole, I have drilled this out at the bottom of the shock to 1/2" which is the correct diameter for the bottom damper fixing to the Vertical link and I have no problems at that end with spacings as it fixes to a 1/2" Stud on the Vertical Link. 

 

It's the top end that's the problem

 

One possible solution is to try and find some Cotton Reel type Polybush or Supaflex bushes that are the correct width to suit the top extension brackets, have a 5/8" diameter hole and are the correct diameter to be a tight fit in the Koni 80-1717 Damper Eyes? 

 

I could drill out the Metal sleeve completely to give a 5/8" diameter hole, then space the gap out between the damper eye bush and the top bracket with the right number of 5/8" diameter hole washers, but would rather not go down this route (Seem's a bit of a bodge to me?) 

 

Hope I've not waffled on to much but can anyone think of a better solution, or is the correct size Cotton reel type Polybush the way to go?

 

Regards

 

Gary

[Peaks]

Hi Gary,

 

I've got a rotoflex MKII Vitesse (well, Canley CV conversion to be precise...) and have fitted Koni classic shocks to mine as well.

 

The top bushes in the Koni classic shock absorbers suitable for the non rotoflex cars fit fine. At least they did ten years ago when I fitted mine. 

 

Failing that, after a nightmare with some AVO bushes on my old Reliant Scimitar I know that Superflex will make bushes to your specifications - for a price!

 

Hope I've understood your post correctly & that helps. 

[Peaks]

 

Just an after thought; I assume that all the top brackets are the same and have the same size drillings? But as with all assumptions could be wrong! Where did you buy yours? 

[Gary Flinn]

I got the Top Brackets from Chic Doig, they are drilled specifically to suit the 5/8" Diameter sleeved Bolts?

 

I have measured the width of the gap in the Bracket were the top eye of the damper fits and it is 35mm, the width of the Damper Eye Mounting is very narrow at only 18mm on the Mini 80-1717 Dampers!

 

So I have a Gap of 17mm or 8.5mm each side to fill?

 

The Original Herald/Vitesse style type Damper bushes (Part Number 102987) are not the correct size or shape for the 80-1717 Damper eyes, so I cannot use these.

 

Superflex and Polybush both do a wide range of Cotton Reel type Damper bushes and also two Piece type Top hat bushes, I suppose I will jush have to look see if one of these wil be the right dimensions for width (35mm), Eye diameter (26mm) and also 5/8" internal diameter (15.875mm) to suit the Sleeved Bolts.

 

I don't really want to get special bushes made (Sounds expensive!), it may be worth a Call to Chris Witor at Superflex and see if he can recommend a Standard type Bush that will do the job?

 

I suppose if I cannot get a Bush the exact correct width, I can space the gap with some 5/8" diameter Hole Washers each side but not it's not ideal?

 

I could have bought the Telescopic Damper & Brackets off the TSSC but I wanted to get the Koni Dampers to match the front of my Car and the 80-1717 types are the correct open & closed lengths for correct suspension travel with the Mk2 Rotoflex type suspension.

[Cookie]

I recently replaced the bushes on my Koni rear shocks on a GT6 and just used the standard 2 part bushes.  I also changed the top bolts to the shouldered ones used on the standard non roto cars and fitted them without any metal sleeves, works fine for me....

 

There is a post about it here in my blog :-   http://cook1e.blogspot.co.uk/2012/10/you-should-always-check-simple-stuff.html

[Gary Flinn]

Andy

 

Do you know what model of Koni Damper you have fitted?

 

The width and diameter of the 80-1717 ones are smaller than the normal 80-1389 type recommended by Koni for the Herald/Vitesse/GT6/Spitfire so I don't think I can use the standard 2 piece bushes?

 

I have attached a Picture of the 80-1717 and the Drawings Koni e-mailed to me of the 80-1717 & 80-1389 Dampers.  

 

I reckon a two Piece Top hat shaped bush of the correct diameter and width is the solution?

80-1389.pdf

80-1717.pdf

[Gary Flinn]

Reckon I've solved the problem

 

Ordered a set of Top Hat bushes from Superflex today, these are the correct diameter to suit the Koni Damper Eye's. 

 

They also have the correct diameter hole for the Shouldered fixing bolt. 

 

They are slightly to long and will need trimming to be the correct length, but I have been advised this can be done with a Lathe and a Stanley knife by Chris at Superflex. 

 

Just need to get this done then I can get the Dampers, new top mounting brackets and the refurbished Spring all fitted together

 

Photo's to follow when I can get a spare day and my Mate can lend a hand with the Spring Lifting Tool!

 

The joys of Rotoflex Couplings and Mk2 Suspension

[Gary Flinn]

A bit more Progress with the Telescopic Damper conversion on my Vitesse Mk2.

 

I managed to get everything trial fitted, Bushes & Spacer washer into the Damper Eye and then got the shouldered bolt installed to check everthing fits and I'll be able to install

 

Just need to arrange a bit of help and a suitable nice day (We had a Tornado here yesterday )

 

Gary   

[Gary Flinn]

A couple of Photo's explaining progress so far?

[Peaks]

What was the part number for the correct bushes Gary?

[Gary Flinn]

I can't seem to copy and paste the Link for the Correct Bushes?

 

The Superflex Part number is SF374-0365-95KSS

 

However check with Chris at Superflex, I was supplied with Blue (80 Shore I think?) Bushes and I didn't need the Steel tubes, I was charged £4 each plus the V.A.T.& Postage.

 

Regards

 

Gary

[Gary Flinn]

Finally fitted the Refurbished rear spring at the weekend, well worth all the effort the ride is far better

 

Next job some decent wiper blades?