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Discussion Starter #1
Sp I finally got some swingarm spools in. I lifted the front and back and noticed the front moved quite a bit. It also dives pretty dramatically under hard braking. Of course, this is partly because I'm fat enough to get a talking to by the doctor.

What solutions have people turned to for springs and/or preload adjustment of any kind? Is it possible on the cheap? I definitely think I should get stiffer springs up front, but I'd like to be able to get it a little more nuanced than just throwing springs in.
 

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Look in the owner's manual on pages 287-289. There are three springs available Soft, Medium, and Hard. Medium is standard, so if you are a heavy person, you could go to the hard springs front and rear.
 

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Discussion Starter #4 (Edited)
Huh. That was quick. Looks like an easybupgrade.

Inthinknjust a stiffer springs agrees with my wallet and ability at the track, however. :p

The ktm website is another version of garbage on mobile. How can I find part numbers for stiffer springs?
 

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I think I would start with a stiffer spring front and rear. I can't find any online parts sources that have the info for the 890. I went into my dealer and they couldn't even find the stock spring.
 

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Yeah, I couldn't find a parts diagram breakdown anywhere. I will ask my dealer today.
 

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AFIK: The 790 had 60/90 progressive fork springs.
____The 890 has a straight rate spring at .90 , I think.
____ You can get springs from Racetec by dimension and spring rate.
____ I weigh 185, so the ./90 springs were good for me.
____ Forks had about 50 mm sag for me, so I shimmed 15 mm to get 35 mm.
 

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Good thread, thanks to all. I am on the plus side of 100kg so looking for an upgrade on the spring front. Here is what I found online (non-US site) - have not yet spoken to the dealer about the parts. There are three springs listed for an 890 Duke in the parts "fiche" and the specs correspond with the values for N/mm listed in the owner's manual for Soft, Medium, and Hard.

97364



97363
 

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Thanks for posting. Can anyone confirm the rate for the front forks and rear spring for stock and heavier? I looked at several sites for the KTM part numbers and no detail is given. I am concerned the next spring up may not be sufficient. C. Dolan was getting 50mm of sag on the stock fork, and I am concerned that the heavier spring is going to still be too light. I don't want to waste the time and money to swap it out and not get what I really need. I am pretty close to 260-265 pounds ready to ride. This doesn't take into account the tank bag I typically have or the rear seat pack.

Racetech lookalike my best option but I need some reference point. I didn't see anything on their site for the 890 yet.
 

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Discussion Starter #10
Does anyone know the fork spring dimensions for the 890?

I'm gonna try to contact racetech to see if they have a spring rate calculator in the works for the 890. The one I used for my SV650 and YZ426F were both apmost perfectly spot on. Barely any adjustment needed after install.

Thanks for the help, everyone.
 

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Not answering your original question, but data that might be useful. The bike has a suspension travel of 5.5 inches front (139.7 mm) and 5.9 inches rear (149.8 mm). I figure ideally, I'm looking for front of 35-46mm and rear of 37-49mm based on my notes, track experience, and reading.

If you're getting much more than 46 you will need bigger springs. In the past, I've used Racetech on my track bikes and even street bikes (2011 Multistrada was too soft for me solo and far from ideal two-up). If you can get the spring rate of the stock spring, they probably have a spring with the numbers you will need. I would do the rear too if you're a big person as preload is a bandaid... not a fix.

Sag as delivered with me and full gear on it (160 lbs without gear):
  • As delivered front: 19 static, 40 with rider
  • As delivered rear: 3 static, 24 with rider rear at 4.5 turns preload
Changes made and result:
  • Adjusted rear to 2.5 turns which got me 4 static 28 rider
  • Adjusted rear to 1.5 turns to 7 static and 31 rider
 

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Discussion Starter #12
My experience with rear vs front is similar. Im 50 or 60 pounds heavier, and between 4 and 5.5 turns of preload, it starts to feel right for my beginner/intermediate track pace, although i havent had a chance to actually measure it.

I dont have any complaints with the rear at all, actually, though I'm not a suspension expert!
 

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I think it is easier to tell when the front is dialed in. You are literally holding the forks with your hand. Every bump is communicated directly to them.

My problem when the rear is off, which is typically when too soft for me, it can throw off the steering angle, typically making it less responsive (increased rake) , make the bike wallow or make it even more wheelie prone. Last thing I need is a short wheelbase, high HP, squatting even more under acceleration. All I end up with is a unicycle.
 

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Discussion Starter #14
Fair point. I dont quite have the panoply of bikes you do, so my experience with good suspension has been "the front isnt making my ability to adjust mid turn absolute trash" and "the rear isnt doing the pogo stick thing!" The bar is set low for me, so the 890 is comparatively perfect already. The front dives but it's still sharp when steering mid turn, so there isnt much I can identify that's 'wrong' or not. :p
 

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The 890 is pretty good, and would likely be great for 90% of the riding I do if I weighed what a typical rider does. :cool: Once you ride a bike that is well setup for you, it is like trying to unsee what you've seen. It is hard to go back to mediocre.

When I first started riding, to make my bike go faster, I usually invested in motor parts to increase the HP. That would be wonderful if like was made of 1/4 mile or 1/2 mile straights. After a few years I started to invest in suspension and brakes and found my laptimes dropped more than by even when I had pretty massive HP increases. Now that stock motors are so good, and serious increases in power not cheap to get (outside of maybe flashing a supercharged Kawasaki), it makes even more sense to upgrade suspension and brakes.

Of course with the 890, just dialing in the pretty good stuff it has may be enough. I'll start there and see if it is worth spending any more. It is such a fun bike for me it is worth investing in. For me it also has been a great teaching too to show my kids how a "slower" bike can actually be faster on a lot of roads. The 890 is really a bargain at its asking price, at least if all the software options were included instead of being tacked on.
 

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Discussion Starter #16
Hey guys, i found part numbers for heavy springs on sparepartsfinder.ktm.com

Front: 95010101S mainspring (38.2) 8.5-350 set

REAR: 91010428 Main Spring (59) 162-195 dampen

Hope this helps anyone not going the racetech/nonOEM route.

Someone mentioned earlier theres a light medium and heavy option, and thia is consistent with ktmpartsfinder.

Considering my windscreen and rear stand spools are a month and not arrived, I imagine these would take an age to get right now.
 

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2020 890 Duke R, 2009 R1
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Also, WP has released suspension upgrades for the SDR and 890 Duke R. Have a look here: WP Suspension Announces Upgrades For KTM 890 Duke R And 1290 Super Duke R - Motorcycle.com News
Found the front kit on a UK site at 1,735 pounds. That is NOT cheap, though I'm still interested.

I found the rear shock preload adjustability to be perfectly in range for me (and I'm near 220lbs), though with the rear effectively raised up a bit, the front forks want to operate a bit below the half-way mark. I backed out a little of the preload in the rear and added some compression damping, which does seem to get the "rings" closer to the center of the forks. Not sure what weight springs I would end up using with the cartridges.
 

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Had a chat with my dealer - they recommended starting with the Hard (162 N/mm) rear spring. It is on order - will post here with impressions in a month or so.
 

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Had a chat with my dealer - they recommended starting with the Hard (162 N/mm) rear spring. It is on order - will post here with impressions in a month or so.
I think you should change the rear and front at the same time as a set. Having a hard spring in the back only will add more weight to the front.
 

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^^^^ what he said. The suspension should work synergistically. If you up the rear, it can put more weight on the front, thereby exacerbating a situation where you already have a week spring for your weight. If you are using saddlebags, and/or a trunk, or some sort of luggage, then just changing the rear spring rate might make sense. Of course, all this presumes that in the first class they got both spring rates right for a "normal" person.
 
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