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Discussion Starter #1
OK - braking gurus!

My question is : Do you think the difference will be palpable?. I really do NOT ride on my brakes - but I like having more safety margin.

My interest was indeed piqued by the Rottweiler kit. And with the 890R sporting 320mm, which are basically two 690R discs - my interest has been re-piqued.

The maths suggest about a 7% increase in surface area/revolution.

I know that Brembo and others do replacement discs that will drop on - but to avoid any potential hassles - I'd prefer them to have KTM emblazoned all over them. I have to be really cautious that "changes" are not visibly so. PP discs might work out a tadge more expensive than pure Galfer - But the KTM logo will convince testers.

I know that @EvansB2 likes the wave discs - But I'm not a big fan of profiled discs based on the looks. I am willing to be convinced - but I'd want some empirical convincing. The 890R discs are about 20% less than profiled ones.

I cannot see me changing calipers and M/C - just because of the cost. M/C - maybe (later) - And if so the 890R model.
 

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Honestly, I doubt you would notice any difference. Pads you would notice the most. Different master you would notice.
 

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I just went for a pad change, and holy **** what a difference. EBC HH ****** great stopping power with little finger effort. Brakes went from a wooden low initial stopping power to two finger braking control. nothing wrong with the stock setup other than the pads.......Ive now ordered a set of EBC for the 1290GT.
 

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OK - braking gurus!

My question is : Do you think the difference will be palpable?. I really do NOT ride on my brakes - but I like having more safety margin.

My interest was indeed piqued by the Rottweiler kit. And with the 890R sporting 320mm, which are basically two 690R discs - my interest has been re-piqued.

The maths suggest about a 7% increase in surface area/revolution.

I know that Brembo and others do replacement discs that will drop on - but to avoid any potential hassles - I'd prefer them to have KTM emblazoned all over them. I have to be really cautious that "changes" are not visibly so. PP discs might work out a tadge more expensive than pure Galfer - But the KTM logo will convince testers.

I know that @EvansB2 likes the wave discs - But I'm not a big fan of profiled discs based on the looks. I am willing to be convinced - but I'd want some empirical convincing. The 890R discs are about 20% less than profiled ones.

I cannot see me changing calipers and M/C - just because of the cost. M/C - maybe (later) - And if so the 890R model.

I know..still... that was not the question but yes: changed the discs to PP waves ones, and yes, big difference.
Much lighter when you install them (nothing can be wrong about that) and feel more braking power.

So throwing in EBC pads on top...although i did not do it just yet, i’m sure you’ll get supersport like planted feel.
So before any master cylinder, new calipers Stylema blablabla...:
1. pads
2. discs
 

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EBC HH's made a difference on every bike I've had since the late 90's.

You just can't throw 320's on, you'd have to space the caliper out too, or get different calipers. Unless you're racing, I doubt you'll feel a difference.
 

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Discussion Starter #8
EBC HH's made a difference on every bike I've had since the late 90's.

You just can't throw 320's on, you'd have to space the caliper out too, or get different calipers. Unless you're racing, I doubt you'll feel a difference.
4*10mm thick spacers M10 clearance and 20mmOD. And 4*10mm longer caliper bolts from KTM. Exactly what Rottweiler provide. Hardly a Rocket Science thing. Already have some CNC 7075 Spacers - odd that :wink:

But seems to me a no brainer that if you want to lighten the front unsprung weight and go to alloy centered discs then one might as well go to 320 as well. So either 320mm profiled disks as Rottweiler or 320 890R discs.

Also worth noting that the JJUAN calipers were originally designed for 320mm discs. They would however not work well with 340mm. This from mates here that race at club level and have JJUAN fitted. Not on KTM though.

Obviously one would fit new pads with new discs and they'd be EBC HH.
 

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If you were racing on the edge with constant high speed braking on the track, yeah, maybe you'll see the benefit of the extra 20mm but in all reality with street riding, there's no extra safety margin to be gained. The stock brakes will lock the front wheel and engage ABS no problem. If you want the "cool" factor of having 320mm discs, then they certainly won't be a downgrade (still lighter than stock discs and I believe about a pound heavier than the 300 discs). Like others have said, you'll see the best benefit from pads and a MC swap. Getting the brake feel how you want it is a great benefit. The mechanical and thermodynamic capability in the system is already there.

Who told you the stock JJUAN calipers are designed for 320mm rotors?
 

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Discussion Starter #10
Who told you the stock JJUAN calipers are designed for 320mm rotors?
I think I have seen on JJUAN somewhere MAX 320mm. But like I say I have a mate here in Spain who races and builds bikes for other racers - The basic JJUAN calliper as on the 790 was made for 320mm - leastways that's what they say. Generally he fits Brembos anyway - but every so often a bit of local sponsoring happens.
 

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With larger discs its going to make removing the callipers a tad more difficult, even now with the stock callipers i have to prise the pads apart to get enough free play to get the caliber off, my 1290 takes some pressure on the pads to get enough play to remover callipers. That stunt guy on here has no problem doing stoppies on the stock set up. The stock setup is great with better pads, but we all like a little bling, for me its always suspension where my $ go.
 

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Discussion Starter #12
we all like a little bling, .
Yeah - and tbh that's what it would be if I did it. Part of MY problem is that I am highly inquisitive and when an idea hits me I have trouble letting it go.

My local suspension guy has made me calm down. Thanks to all here - the brake thing is fading too. Moving the lever perches solved the lever reach issue I had.

So I'll soon get bored and be asking more absurd things :wink:
 

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we all like a little bling, .
Yeah - and tbh that's what it would be if I did it. Part of MY problem is that I am highly inquisitive and when an idea hits me I have trouble letting it go.

My local suspension guy has made me calm down. Thanks to all here - the brake thing is fading too. Moving the lever perches solved the lever reach issue I had.

So I'll soon get bored and be asking more absurd things

If you like the little bling, then for sure the PP Wave discs.
- Petal
- lighter
- more friction
 

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If you like the little bling, then for sure the PP Wave discs.
- Petal
- lighter
- more friction
Except I really do not like the look of wavy discs - never have. When did you last see a GP bike with wavy disks?.
Ok ok ....

To be fair, I did not buy them for the look. The fact that they are so light versus the OE ones and add brake feel versus original discs was the trigger.
Can’t wait to match them to real brake pads like EBC ones
 

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Discussion Starter #18
When's the last time you saw a streetbike with 340mm carbon discs? lol
Well if they were being sold - somebody would fit them I'm sure.

If wavy ones really offer more feel & power etc then I can be convinced. What is then a surprise is that KTM decided to fit the 320mm discs from the 690 onto the 890R rather than PP wavy ones. At the moment anyway they don't suggest a PP upǵrade there.

What I what to do is pop to a KTM dealer with a magnet and test the 890 disc centre plates. My local dealer does not have an 890. And wont. They're offroad guys really.
 

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Well if they were being sold - somebody would fit them I'm sure.

If wavy ones really offer more feel & power etc then I can be convinced. What is then a surprise is that KTM decided to fit the 320mm discs from the 690 onto the 890R rather than PP wavy ones. At the moment anyway they don't suggest a PP upǵrade there.

What I what to do is pop to a KTM dealer with a magnet and test the 890 disc centre plates. My local dealer does not have an 890. And wont. They're offroad guys really.
You kinda answered your own question there. KTM went to 320 discs on the 890 because they already had them on the shelf and they compliment the new Brembo calipers.

I can't say the wavy discs added any "feel" because I changed to EBC HH pads at the same time but the weight difference compared to stock was significant.
 

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GP bikes and Super Bikes don't have wavy disc's because increasing the edge diameter would cause more cooling compared to round rotors. Cold disc's aren't going to help braking.
 
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