Projection quad link jack up kit.
 

I've been using this for a few years now, great piece of kit. I was washing my bike yesterday after a few weekends out trail riding and noticed they seem bent/curved. I don't remember them being like this when I fitted them.

If anyone has a set on there bike can you check and see if yours are curved. I'll stick a picture up in a minute for comparison.

I checked their website and all the ones listed look straight. They also say they're guaranteed for life so I've dropped them a message.

Cheers
Jon

This is the only pic I could find of the actual xt660z links cheers XT660.com :thumbsup:


http://i607.photobucket.com/albums/t...psw7n4fq5r.jpg

Here's mine.

http://i607.photobucket.com/albums/t...pswvsr5eic.jpg

And a piece of straight stock as a comparison.

http://i607.photobucket.com/albums/t...psicwxy8ko.jpg

Or am I just imagining things haha. :wicked01:

They look bent to me but you know what my eyes are like!!
All the best Mark


Sent from my iPad using Tapatalk

They look bent/deformed to me, you could see why it might happen with the forces going diagonally across the plate. Would be good to hear their response, good luck.

Been in touch with projection compnents today. Long story short yes I've bent them....... maybe I'm a little harsh on my Tenere, I expect a lot from it haha. :darth:

Projection both apologised to me for their product bending and then congratulated me for being the very 1st person ever in history too take them up on their lifetime guarantee. :smilies0346::laughing6::smilies0979:


fair play too Projection they stand by their products ( which are the dogs ****** by the way.) and are making me a beefed up super set, set free of charge.
They offer a lifetime guarantee and honour it.

So when the new ones arrive I'll throw them in and go and give them a good :spanking[1]:

Great result mate.

superb result and great customer service.

Just checked mine and they're as straight as a die after nearly five years on the bike. Still is good you highlighted this and made me check them. Impressive customer service too.

Maybe towing that trailer of yours around might have had something to do with it to jon660z?

I'm wondering how they could bend when they are under tention...
if it was compression I could see it....
Also the weakest direction is side ways... but they have bent ?
in the other direction....
I would say they were made like that....





...

Are these the 'adjustable ' dog bones...? I was thinking of getting some so I can occasionally lower the bike for off roading....Steve

Yes they are adjustable, but not in the sense that you can do it quickly without tools! You need to remove the dog bones and replace them in a different position to make the adjustment.

They do jack-up and lowering versions, but interestingly neither has a "stock" or zero position. They start at +5mm or -5mm.

Jack-Up

Lowering

Also worth noting that, if you have a centre stand fitted, the links can only be fitted in two of the four positions without fouling the stand's bolt threads protruding out of the nuts (although the bolts can be reversed to avoid this issue).

Cheers Pleiades, good info. I had this misguided idea five minutes with the spanners would see the bike lowered. ..! Steve

Whilst the dog bones (linkage plates) are under tension the vast majority of the time, if the suspension 'tops out' (hits the internal bump-stop in the shock) with any inertia, they will momentarily be under a significant compression force. I suspect that this is what has happened in Jon�s example? A combination of a high spring rate, low rebound damping and the action of a trailer�s weight pivoting and acting like a lever increases the chances of �topping out�. With a trailer, as the rear end of the bike rises, the trailer inclines backwards and all its weight will effectively shift rearwards, increasing upward leverage on the hitch, in turn further lifting the rear of the bike (extending the suspension) and with a greater magnitude of force/inertia. This is an exponentially increasing effect too; the more the rear suspension extends the greater the effect the trailer will have on extending it further.

You guys are too clever, ive no idea how they have bent but projection now have them and have comfirmed it. They are bent. Ive had a pdf image of the new links they are mighty. Ill post a pic up when they have been made,

Steve i adjust mine when i go trail riding as my offroad wheelset sits a good inch and a half taller than my road wheelset. So i use the +5mm offroad and the +25mm on road. Keeps.my geometry very similar.

Perhaps just a strange coincidence but before i shipped them off i had them measured at work on the co-ordinate measuring machine and how i had them on the bike at the +5mm setting (for offroad) now measured exactly the same as the standard links too within a tenth of a mm. They where also just beginning too bow outwards. 0.78mm over the length of the link.

Now Pleiades, you sir have a very good point about the extension of the shock. But not with relation too my trailer. When i ride offroad, contrary to most people i actually run very little rebound damping (ohlins piggyback shock) I find this helps the Teneres traction on the loose rocky terain i ride on,.but can leed to the rear end bucking under me on high speed jumps and big landings, its a trade off i know as more damping would help the landings but take away the wheels ability to track the ground on fast rough terrain.
Its a trade off and i ride more fast rough stuff than I do jumps. But maybe this is how they have become bent?? That and running them in different settings often. Maybe be t one way and then the other??

On the road with the trailer (and or luggage) i run lots of rebound and compression too counteract the lever effect the trailer can have. The trailer has over 3500 miles on it now the biggest difference was made by actually learning how too load it properly haha.
Anyhoo. New massive links in the pipeline.

Ive got it.......... Pleiades your a genius. You got me tbinking and looking through old receipts. Ive had the links long before I bought my ohlins shock. Which i in turn bought because the Sachs unit died a miserable leaky death. That sucker was like a pogo stick for a good 3 weeks whilst offtheroad sorted my new shock out. Topping out many many times.
Ill bet thats when the damage was done.
I change the links so regularly, but very rarely clean them or inspect them. Was only this time as i was under there removing my bash guard for straightening that I cleaned everything so it wouldnt be such a mucky job.

10 points for Pleiades.

Excessive topping out inertia resulting in bent linkage plates... a fooked shock (sans oil) will definitely be a BIG factor as there won't by any rebound damping to speak of at all. As a matter of fact, the Sachs shock has woefully poor rebound damping straight out the box, never mind when on its last legs! So it's probably been smashing into the top-out bump stop for many a mile, giving everything else in the linkage a right old hard time of it.

Glad you've got to the bottom of it!

Why havn't they taken the weakest option and bent sideways...

Because they are under tension so effectively are always being pulled straight?? Another thought i had ia that maybe they arnt "bent" as such but "stretched" as the bolt holes are off the centre line of the links. Think of a banana if you pull it from either end it will straighten out. And ita effective length will be longer.

I think im correct in saying that the shorter the links the higher the rear end. Mine are lift links yet they were near as makes no difference the same length as the stock ones when i removed them.

Heavy loading and jumping a 200+kg bike with +110kg rider could have bottomed the shock and the links were pulled straighter by the force?? I used to use a hyperpro progress spring along with the progressive linkage on the Ten would have made it virtually impossible too bottom out. All that pulling force would have been on the links.

Discuss.................

The numbers are made up and the drawing crappy but do you get the idea?? The dashed line is the load centre between the bolt holes.

http://i607.photobucket.com/albums/t...pszh5185rf.jpg

Probably, I’d assume, due to the clamping forces of the bolts holding the plates against the bearing collars meaning the whole thing is kept dead square; the two linkage plates are perfectly parallel and the collars/bearings/bolts are perpendicular to them. The whole thing is dead-square. The resultant forces in the linkage plates will be exactly and directly opposed to each other, whether under compression or tension. The plates would only bend outwards (or inwards) should the arrangement become out of square and the forces become off set to one another. For example a worn needle roller bearing, worn collar or a loose bolt could potentially cause outward or inward bending. The main thing though, is that even if they were made of material too thin/weak to start with (which the Projection Components items most certainly aren’t) they would more likely fracture, crack, tear or split under the tension that the system is under 99% of the time, long before they ever had the chance to bend under compression.

Banana is a good example and yes, because of the bend, your links have ended up longer and a similar length to OE. The shorter the linkage plates between hole centres the higher the bike by a ratio of 1:3 so 5mm closer hole centres will give approximately a 15mm rise at the rear.

Theoretically the effective load is between the centre holes, but it isn’t in reality with the projection links because the holes have no material between them to transmit that force where it would want to go (between the holes centres/dashed line on your drawing/yellow line on mine below). In a normal stock linkage plate this would be the case. The actual force in the Projection Components linkage plate is transmitted along the top edge of the (as orientated in your drawing) – following the red line. This creates a moment arm (blue line): the product of the a force and the distance from a its reference point (hole centre in this case). This moment arm creates torque, and that torque, because the forces are acting in opposing directions, acts in different, opposing directions at each end of the arm, resulting in the bending (or stretching if you like) observed. This torque reaction will apply equally whether the opposing forces are pulling or pushing against each other (topping/bottoming-out); it just means it would bend the other way.

http://i864.photobucket.com/albums/a...psn8xoltze.jpg

In layman’s terms, here’s an example that might help: If you get a four hefty chaps at each end of a traditional style hospital bed like this sort of thing…

http://i864.photobucket.com/albums/a...ps0jj5yysl.jpg

…and they grab the head and tail ends in line with the mattress base frame and pull, or push, the bed will not bend in the middle. If those hefty chaps now hold the bed at the top of the head rails and tail rails and pull, or push, with exactly the same force, the bed will bend in the middle (upwards if pulling, downwards if pushing) because of the moment arm introduced (additional distance from the force’s reference point which is level with the base, the link, or couple between the two bed ends) and its resultant torque.

In a nutshell Jon, all of the above was the result of your shagged OE Sachs shock allowing the suspension to crash into the bump-stop on compression and extension without any control/damping at all. Personally I think the PC links are more than man enough for the job if everything else is in GWO; they just become the weakest link in the chain if something else in that chain craps itself!

And crap itself is exactly what it did, all over my rear tire, luckily for me this was half way across rudland rigg, a looong, fast (50-60mph) green lane. Light gravel and plenty of jumps to empty all the oil from the shock and scrub the oil from the rear tire.

Riding the steps at the far end was fun with no damping haha. Still i did a better job than my friend Pete

http://i607.photobucket.com/albums/t...pszsckvkyy.jpg

Anyhoo here are the new beasty links.

http://i607.photobucket.com/albums/t...ps9sjsomcf.jpg

Compared too the old ones.
http://i607.photobucket.com/albums/t...psw7n4fq5r.jpg

I was looking on their website to no avail for same..Have you by chance a reference/part number please?


The holes in mine are oval after 70,000kms of hard use and I need to upgrade.


Thanks

:)