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Discussion Starter · #1 ·
Well I've done it. Im generally very happy with the 790s suspension, but today i visited our Ohlins service centre to chat about shock options, well he had in stock the R1 Nitron and the R2 Nitron. Both nice. the R2 a couple of hundred more, but had better adjustments for Reb and Comp. I went for the R2, i pick it up tomorrow, but he didn't have a suitable spring for my weight, but he has some on back order. So tomorrow i shall pick it up and fit it. The WP shock is already sitting on the bench. Less than 15 mins to remove (so easy once bike raised) Stock shock is 130-160 through its progressive spring rate, and the spring fitted in the Nitron is somewhere in the middle, so will try it, but I'm thinking id like a softer set up (I'm 76kgs). i shall report back once fitted. PS Nitron shock looks classy.
 

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Let us know how it feels. I am leaning toward that NTR3, which is available here through Fast Bike Industries. Black or blue spring?
 

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Discussion Starter · #4 · (Edited)
Heres the shock pre fitting. Well i got them to fit a softer spring. The stock spring rate is 130-160nm being a progressive spring, so i asked for a spring around the 130nm, they fitted a 750Fp (foot pounds, its an English shock) well it was perfect. I checked Sag. 40mm rider sag, 13mm free sag. Absolutely perfect for road riding on all road conditions. Test ride went great. Stopped set the rebound at 10 clicks out and then stopped and set the compression at 8 turns. Sensational. I love this shock, the 790 suspension was goodish before, its now fantastic. Ive now ordered through the shop on the the guys recommendation a Matris fork kit. Got to wait a month now. But so so impressed with the Nitron shock.
 

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Too bad they don't have matching front cartridge kit for Duke 790, for this reason I still consider K-Tech set.
Can't see why these wouldn't pair well with Ohlins, Andreani, WP or any other available cartridge kit for the D790.
 

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Discussion Starter · #7 ·
Can't see why these wouldn't pair well with Ohlins, Andreani, WP or any other available cartridge kit for the D790.
Absolutely. And also you see on many factory suspension set up. i.e. Showa forks Ohlins shock, or SACHs shock matched with a Mazocki forks etc. He told me about the Matris set up as he has been to their factory, and explained the extra internal workings that other makes don't have, it was something to do with the rebound on full extension. The guy is NZ guru like Dave whats his name?. it will come to me. But mix and matching brands front to rear is a common theme.
 

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it was something to do with the rebound on full extension. .
I know Maxton also have a rebound top-out prevention spring inside the hydraulic part of the cartridge. And I have recently read somewhere of a hydraulic brake for this too. Might actually have been Matris tbh.

My local suspension guy fitted them for me (on my R3) and he was duly surprised and impressed. He had not seen this on any of the other "off the shelf" options.
 

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Discussion Starter · #9 ·
I know Maxton also have a rebound top-out prevention spring inside the hydraulic part of the cartridge. And I have recently read somewhere of a hydraulic brake for this too. Might actually have been Matris tbh.

My local suspension guy fitted them for me (on my R3) and he was duly surprised and impressed. He had not seen this on any of the other "off the shelf" options.
I think he said it had anti cavitation valve seats for when the fork is toped out. I can't remember if he ordered me the 20mm kit or the 25mm kit.
 

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DaveNZ: I'm considering a Nitron R2 shock + a Matris fork kit....so I'd really appreciate your update on:

- The key differences your Nitron-Matris setup made to the ride quality and cornering characteristics?

- Which fork springs you settled for?

- Can the average home mechanic fit the Matris kit, without specialist tools?

Like you, I'm 76 Kgs (in full riding gear) + I ride with a 13 Kg tool bag strapped to the pillion seat :)
My riding is twisties - no commuting. Plus 1-3 long distance sport-touring trips per year.

With many thanks in advance.
 

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Discussion Starter · #13 ·
DaveNZ: I'm considering a Nitron R2 shock + a Matris fork kit....so I'd really appreciate your update on:

- The key differences your Nitron-Matris setup made to the ride quality and cornering characteristics?

- Which fork springs you settled for?

- Can the average home mechanic fit the Matris kit, without specialist tools?

Like you, I'm 76 Kgs (in full riding gear) + I ride with a 13 Kg tool bag strapped to the pillion seat :)
My riding is twisties - no commuting. Plus 1-3 long distance sport-touring trips per year.

With many thanks in advance.
Hi Mark, your similar weight as me. The R2 shock with a slightly lighter spring (mines a 750ps) but will check, Nitron came with 860 from memory. Great shock, perfect for all road conditions. My Matris fork kit came with too heavier springs (8.2 kn from memory) couldn't get the sag i wanted. shop didn't have any lighter springs to fit, so in one leg (Reb) he fitted a 6.4 with a machined spacer to match the length of the stock springs with the right amount of preload. Reb leg has the supplied matris 8.4 spring. (together i get an av of 7.4kn) i could get 40mm rider sag with this setup. (after dyno and spacer adjustment, get 45mm sag with 6 clicks of preload) Ok, now problem, with lighter spring setup, the comp was too harsh and the Reb too slow. i tried 2.5 weight oil with 20mm less measured oil height. Worked ok, but not perfect, and still had some high speed dampening harshness. Forks returned, dynoed, and new compression valves fitted, i think he honed out the rebound valves also, so at 14 clicks out the rebound was/is perfect, and never to adjusted again (if i stay same weight) It is now perfection. He said the Matris is extremely high quality, but suited to a 85 plus kg rider. and Matris don't make any lighter springs to fit. Id say if you have access to a good suspension tuning shop, Matris is worth the effort, other wise id go Adreani kit. Nitron is real quality out of the box, other than the lighter spring, its good to go from the factory. What I've noticed is you sit higher on the bike as theres less initial sag, but the suspension works amazing, it feels like its soaking everything up instantly, where as the stock setup sits lower due to soft initial spring travel, and has a floaty feeling when the bike is unloading off bumps, or fast left to right transitions. The stock set up is ok, but it doesn't compare to this new set up. Control of rebound is very important, and difficult with a rising rate spring (stock). Fixed rate for the rider are the way to go. Hey hope this helps. In another section i have posted my dyno results from the new Matris fork kit.
 

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Hi Mark, your similar weight as me. The R2 shock with a slightly lighter spring (mines a 750ps) but will check, Nitron came with 860 from memory. Great shock, perfect for all road conditions. My Matris fork kit came with too heavier springs (8.2 kn from memory) couldn't get the sag i wanted. shop didn't have any lighter springs to fit, so in one leg (Reb) he fitted a 6.4 with a machined spacer to match the length of the stock springs with the right amount of preload. Reb leg has the supplied matris 8.4 spring. (together i get an av of 7.4kn) i could get 40mm rider sag with this setup. (after dyno and spacer adjustment, get 45mm sag with 6 clicks of preload) Ok, now problem, with lighter spring setup, the comp was too harsh and the Reb too slow. i tried 2.5 weight oil with 20mm less measured oil height. Worked ok, but not perfect, and still had some high speed dampening harshness. Forks returned, dynoed, and new compression valves fitted, i think he honed out the rebound valves also, so at 14 clicks out the rebound was/is perfect, and never to adjusted again (if i stay same weight) It is now perfection. He said the Matris is extremely high quality, but suited to a 85 plus kg rider. and Matris don't make any lighter springs to fit. Id say if you have access to a good suspension tuning shop, Matris is worth the effort, other wise id go Adreani kit. Nitron is real quality out of the box, other than the lighter spring, its good to go from the factory. What I've noticed is you sit higher on the bike as theres less initial sag, but the suspension works amazing, it feels like its soaking everything up instantly, where as the stock setup sits lower due to soft initial spring travel, and has a floaty feeling when the bike is unloading off bumps, or fast left to right transitions. The stock set up is ok, but it doesn't compare to this new set up. Control of rebound is very important, and difficult with a rising rate spring (stock). Fixed rate for the rider are the way to go. Hey hope this helps. In another section i have posted my dyno results from the new Matris fork kit.
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Hey Dave

MANY THANKS for your comprehensive + fast reply...MUCH APPRECIATED!

I'd seen your posts in other suspension threads, but was not sure of your latest fork situation. Glad you're sorted now.

Even if I did have a good suspension shop near me, I can't afford the extra labour your guy/s put into the Matris kit. Shame, as I know Matris are much higher quality than Andreani.

A helpful learning from you is that Matris don't make a kit for lighter rider, i.e. lower rate springs and valving. I'd call WP's Aus distributor, to see if they'd do an EOFY deal on an Apex Pro kit - but even that kit only provides +/- 3mm of preload adjustment. So I'll suss K-Tech.

Yes, every comment I've seen says Nitron's R2 is fab out of the box.

Many thanks again for your helpful update Dave!
 

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Any updates on the Nitron Dave?
The only criticism I've read of the Nitron is on some models there is no grub screw on the preload collet, and the preload can back itself off. Can you confirm if your R2 has one?
Any pics of the cannister mount? Did it come with anything?
 

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Discussion Starter · #16 ·
Any updates on the Nitron Dave?
The only criticism I've read of the Nitron is on some models there is no grub screw on the preload collet, and the preload can back itself off. Can you confirm if your R2 has one?
Any pics of the cannister mount? Did it come with anything?
Hey the Nitron does come with a grub screw, its hard to see in the packet, but its a clear plastic one. Ive never fitted it, and the collet has never unwound, i asked the suspension tech whether i should fit it, he said they haven't come across any loosening.....Any updates??, um, its fuking awesome.
 

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Heres where I read it:
 

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Discussion Starter · #18 ·
^^, i guess they never looked in the packet when removing the shock and fitting it. Ill hunt for mine, its still in the original box.
 

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I fitted mine, it's a bit irritating if the lower collar has the hole in a weird spot. There's so little adjustment at the bottom that I figured it would be more for quick track adjustments so I set sag with the upper.

My R3 came with the reservoir bracket, which I hadn't really seen confirmation on before I ordered the shock. I did have to make spacers to fit behind the bracket on the subframe, but I think I saw someone else's shock came with pre-made spacers.

To release the upper shock mount, loosen the engine mount bolts beside the shock bolt. To release the lower shock mount, undo the adjuster nut a little (can't remember the size, 14 or 17 hex/allen I used). Saves fighting and filing away at parts.
 

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Discussion Starter · #20 ·
^^^ I had a lighter spring fitted Rick, and the lighter spring was shorter than the spring that came with the Nitron shock, so i have a good 15-20mm of thread on the bottom to play with.
 
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