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Discussion Starter #1
I'm hoping someone here can get me some info - thanks in advance!

I installed the Misano cartridges last summer and the oem ktm fork seals are now (both) leaking so I'm replacing them along with the fork oil.

Suspension shop owner is swamped and knows he used KWB 5W fork oil but not the level.

Andreani recommends Ohlins 5W oil but my local dealer doesn't have access to it, so....

Anyone know the oil level and can recommend a decent substitute brand other than Ohlins for the fork oil? I believe the parts manager said she has access to Honda, Belray, Motul, etc... but not entirely sure on others.

Thanks!
 

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If you can copy/paste my questions and fire em off to him that would be awesome JD -thanks!!!

Oil I have, gonna grab some LiquiMoly 5W - just need to know the oil amount or height in each leg please.
Prob similar to stock volume, My Matris fork kit gave a measurement without the springs fitted, this added up to be 400mls per leg. I used (came with kit) 5W Motorex, then switched to 2.5W motorex.
 

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Thanks Dave! My buddy/mechanic thought 385-415ml but wanted closer spec so that's perfectly in the ballpark and we'll go with it.
 

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Thanks Dave! My buddy/mechanic thought 385-415ml but wanted closer spec so that's perfectly in the ballpark and we'll go with it.
You can add more, or have slightly less to the recommended volume , a small amount won't make much difference. But say you feel like you want a little more compression mid-full stroke, you could add more (30-40mls) of for a softer mid-full stroke have less. Its basically the stroke compressing the spring forcing the oil through valves and compressing the air cavity. more air cavity to compress=softer mid to late stroke. 400 be smack in the middle id say.
 

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Discussion Starter #5 (Edited)
You can add more, or have slightly less to the recommended volume , a small amount won't make much difference. But say you feel like you want a little more compression mid-full stroke, you could add more (30-40mls) of for a softer mid-full stroke have less. Its basically the stroke compressing the spring forcing the oil through valves and compressing the air cavity. more air cavity to compress=softer mid to late stroke. 400 be smack in the middle id say.
Thanks - and well put!

I'm going to back off the rebound from 2.5 turns to 3 turns out and see how that feels - bumps and potholes are far too harsh so that's option #1 - preload will be next if that doesn't fully get me to where I wanna be feel wise.

400ml it is!
 

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Dang, Rod doesn't use Ohlins oil with them? I can install mine myself, I was just hoping to have him do them with the fancy oil I can't get through Laura. :(
 

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Discussion Starter #7
Dang, Rod doesn't use Ohlins oil with them? I can install mine myself, I was just hoping to have him do them with the fancy oil I can't get through Laura. :(
He used KYB 5W when installing mine last year. I bought LiquiMoly 5W today - hopefully it's similar.
 

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Thanks - and well put!

I'm going to back off the rebound from 2.5 turns to 3 turns out and see how that feels - bumps and potholes are far too harsh so that's option #1 - preload will be next if that doesn't fully get me to where I wanna be feel wise.

400ml it is!
Back off the Comp younglion, a click or so,, use your Preload adjustment to set your sag, i.e.-40-45mm with full extension, to rider with gear aboard. If the ride is still a little harsh, you could try 2.5W fork oil, and if nothing is helping, either lighter springs (sag measurements will determine this) and hone out the valves to suit (Professional job, thats what I'm waiting for at present). Out of curiosity, what springs did they fit (i.e. 8kn) and whats your ride weight (with gear)
 

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Discussion Starter #9
Back off the Comp younglion, a click or so,, use your Preload adjustment to set your sag, i.e.-40-45mm with full extension, to rider with gear aboard. If the ride is still a little harsh, you could try 2.5W fork oil, and if nothing is helping, either lighter springs (sag measurements will determine this) and hone out the valves to suit (Professional job, thats what I'm waiting for at present). Out of curiosity, what springs did they fit (i.e. 8kn) and whats your ride weight (with gear)
I'm just going by the owners manual where it states "If forks are too harsh over bumps, reduce preload (17mm nut on top of each fork) 1mm (full turn out)." Compression is to be backed off if the forks are nervous and moving around mid-corner so I'll also back that off a tad.

I'm roughly 95kg in gear, honestly not sure what spring rate is installed, when ordering you're asked weight and riding style and the springs are based on 10kg increments so I was in the 80-90kg (no gear) and my friend NewBusa on here, he ordered at the same time and went one step lower than me - 70-80kg. Riding style I put street only, they have street track, and track only as well for options.

I looked all over the box they were shipped in and on the invoice - no mention of spring spec on there anywhere - just the part numbers - must have been listed inside the box or taped to the outside so our suspension guy could tell which was which.
 

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Spring rate is usually stamped on the end of each spring. Prob be 8kn, or .85kn in each for you. Fixed rate springs don't get any harder or softer through their stroke. an 8kn if its high quality remains 8 through its entire compression. So more preload verse less preload, all it does is sets your sag-bike balance. (variable rate springs are that, variable through the stroke). so once you set your sag (front) it should remain pretty much that position. (40-45mm) if it was road only. (from memory my stock forks had 58mm sag shock 48, but will check as i recorded before removal to make sure i still got the factory balance between front and rear) Two things i do on my bike set up which i seldom touch once set is fork preload and rebound, once set i don't alter them, i just vary the harshness via the compression. There will be a factory recommended setting for the Compression, and altering it too far from that setting becomes unworkable, i.e. (my forks 20 clicks, factory recommend 12 clicks out, so 2-3 in any direction is all that really is usable. some systems have 8 clicks, so 2 click either side is about the limit) Its all interesting, and I'm lucky i have a mate who owns a Suspension specialist shop, trouble is I'm on the back burner as he's so busy.
 

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Heres my original Sag settings from the 790 before suspension change. Some very large numbers, but the 790 worked fine on the road other than some harshness deep in the stroke (variable springs) At the mo i have settings of rear free=12mm, rider=36, front free=28 rider=41. Im going to fit 7kn springs so i can add some preload (none at present) and get 45mm sag.
 

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Dave, you had 19mm rear free sag with stock? Mine was 11mm free/static sag in the rear, same 39mm front though. I was getting bucked off over bumps, had to drop it to 2nd lightest preload setting (21mm static) to try and balance out the squishy front.
 

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Dave, you had 19mm rear free sag with stock?
Yip, that was after putting more preload on from factory setting-(factory setting 5 seats down from full preload) just checked and 19mm free sag was on 3rd down from top/full.
 

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I wouldn't have thought they'd change spring rates, but perhaps they did? Is yours a 2019? My preload started in the same spot.
 

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I wouldn't have thought they'd change spring rates, but perhaps they did? Is yours a 2019? My preload started in the same spot.
Mines a 2018, it was a demo for its first 2000kms, and it was the shop owners own bike which he was going to keep, he did 2 track days on it and did the initial raise of the preload, i added one more to get rid of some of the rear rider sag. KTM have some strange ideas on the road going suspended bikes, they build in lots of sag, both rider and free-(static) sag, its how they see their bikes working as compliant road bikes, but one size doesn't fit all. But they still work well on their stock suspension, but aren't brilliant.
 

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Just off the origina; box, see pic below:

Air chamber: 100mm
Oil: Ohlins 01309 #5

4212
 

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I guess you should be fine.

Weather here is really getting nice for riding. With the COVID situation not so much traffic as well. I am doing back-road riding almost on a daily basis...
 

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Discussion Starter #19
It's been awesome the past few days and the next 3-4 are looking even better - 15-16 Celcius (60ish F?) and as you say - low traffic on the backroads.

Tires are scrubbed in and so are the pads - however in the Covid world I'm still planning on leaving a LARGE buffer in place as not to add to the high work load of our medical staff and first responders. Still should be able to get a fair assessment of the changes though.
 
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