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Thanks guys, this sounds well worth doing. any ideas why Ktm put such a low viscosity fluid in to start with? To sell their upgraded steering dampers perhaps?!馃
Just looked in my w/shop and found this Fox Gold 20wt fluid :
4561


OK so it鈥檚 a bit heavier I know and its not synthetic and realliy made for my Mtb suspension - I鈥榤 just eager to get it done!
:p
 

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Thanks guys, this sounds well worth doing. any ideas why Ktm put such a low viscosity fluid in to start with? To sell their upgraded steering dampers perhaps?!馃
Just looked in my w/shop and found this Fox Gold 20wt fluid :

OK so it鈥檚 a bit heavier I know and its not synthetic and realliy made for my Mtb suspension - I鈥榤 just eager to get it done!
:p
Synthetic is not required for the damper. That's advertising reduced stiction (great) and moly (also great), will be aluminum compatible, and was made for fork tubes sliding in bushings with multiple forces applied. Our steering dampers are mounted on pivots so they don't really rely on the internal bushings as much as a bike fork.

20wt would also be fine, so don't worry about that. Super Duke 1290 guys are using 15-20wt, and Adventure guys are using up to 30wt to deal with rocky surfaces. One of the owners of the KTM dealer my wife works at is a racer with OCD about his bikes, and used straight 30wt engine oil in the damper for his race supermoto. I already had Belray 15wt fork oil from when I was playing with the pogo sticks in my other bike, so that's what I've been using in 3x 790/890 dampers so far (and one other local 890 needs it too after this weekend's ride).

You only need maybe a tablespoon and a half (looks like just one when you drain it), so just get it done with that 20wt Fox oil! :)
 

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Synthetic is not required for the damper. That's advertising reduced stiction (great) and moly (also great), will be aluminum compatible, and was made for fork tubes sliding in bushings with multiple forces applied. Our steering dampers are mounted on pivots so they don't really rely on the internal bushings as much as a bike fork.

20wt would also be fine, so don't worry about that. Super Duke 1290 guys are using 15-20wt, and Adventure guys are using up to 30wt to deal with rocky surfaces. One of the owners of the KTM dealer my wife works at is a racer with OCD about his bikes, and used straight 30wt engine oil in the damper for his race supermoto. I already had Belray 15wt fork oil from when I was playing with the pogo sticks in my other bike, so that's what I've been using in 3x 790/890 dampers so far (and one other local 890 needs it too after this weekend's ride).

You only need maybe a tablespoon and a half (looks like just one when you drain it), so just get it done with that 20wt Fox oil! :)
OK Rick great!
So watched a couple of tutorials but they鈥檙e not off a 790 and now i have the damper off the bike with circlips and spacers removed and I notice that to hammer from the eyelet end to drive out the seal from the other end I鈥檓 up against the seal with the start of the eyelet mounting. So is this correct? As presumably I鈥檒l be driving one seal in further to get the other out? Or am I just being a dumbo?!!!
:unsure:
 

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OK Rick great!
So watched a couple of tutorials but they鈥檙e not off a 790 and now i have the damper off the bike with circlips and spacers removed and I notice that to hammer from the eyelet end to drive out the seal from the other end I鈥檓 up against the seal with the start of the eyelet mounting. So is this correct? As presumably I鈥檒l be driving one seal in further to get the other out? Or am I just being a dumbo?!!!
:unsure:
What you describe is exactly what Rick did to mine yesterday with a mallet - it takes quite a few taps to get it out but thats the way to free it.
 

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OK Rick great!
So watched a couple of tutorials but they鈥檙e not off a 790 and now i have the damper off the bike with circlips and spacers removed and I notice that to hammer from the eyelet end to drive out the seal from the other end I鈥檓 up against the seal with the start of the eyelet mounting. So is this correct? As presumably I鈥檒l be driving one seal in further to get the other out? Or am I just being a dumbo?!!!
:unsure:
Just do the non-eye end, and you don't need to pull the cap off like the videos. Pull the damper rod by the eye to get it off the stop, hold with one hand over a container and hit with a soft plastic/rubber mallet/dead-blow on the eye end. Hydraulic pressure will do the work without damaging the seal or bushings inside. To get the seal back in (using a small zip tie in the lip to bleed air/oil) I use a deep socket (14mm in my case, but it depends on the outer diameter, mine just fits), damper mounted in my rubber-lined soft-jaws in a vice and hitting the socket with my mallet/dead-blow. If you drive the seal in too far you can drive it back the same way you started, but it may suck in air when it moves, so don't go too far if you can help it.
 

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OK - got it! I had forget about the hydraulic pressure! So yes of course I just needed to extend the damper rod eyelet away from the seal and give it good tap and hey presto!
OK so I鈥檝e filled it with 20wt and mounted it back and I have to say the steering does feel a lot heavier stationary. I鈥檒l have to wait to take it for a ride and see what it鈥檚 like on the move and if it鈥檚 cured the head shaking. I鈥檒l let y鈥檃ll know.
Thanks for the help YL & Rick - Nice one. (y)
 

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Has anyone figured out a way to mount an aftermarket damper?

I really like the one from Mupo. But can't mount it.

Maybe someone has a hack?

Thanks
 

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OK - got it! I had forget about the hydraulic pressure! So yes of course I just needed to extend the damper rod eyelet away from the seal and give it good tap and hey presto!
OK so I鈥檝e filled it with 20wt and mounted it back and I have to say the steering does feel a lot heavier stationary. I鈥檒l have to wait to take it for a ride and see what it鈥檚 like on the move and if it鈥檚 cured the head shaking. I鈥檒l let y鈥檃ll know.
Thanks for the help YL & Rick - Nice one. (y)
Interesting. With 15w I didn't notice much of a difference when stationary. Good luck!
 

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Hey Rick!

Just returned from a little test ride on a mixed route - managed a few gnarly backroads too!
Gave it plenty of gas from the off in Sport mode and even accelerating over a hump back bridge didn鈥檛 faze it! Feels solid as a rock and much more confidence inspiring now - even with the Maxxis rubber - haha! And the heavier steering doesn鈥檛 seem to be an issue either - so win win me thinks!
馃憤
Best
Booney
 
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