Fork Oil Recommendation?

[NotVeryCreative16]

I pulled the trigger on some K-Tech 20IDS cartridges to match my Razor shock. Now I just need to confirm what fork oil to go with and what height I should be filling to. I weigh 250 lbs with gear and went with the 9.5 NM spring. I've done so much reading that my brain hurts but I'm still confused. Should I be looking for an oil that is approximately 16cSt@40? I think that's what I've gathered from my reading. It seems like the Maxima 5W racing fork oil matches that specification. Will that work is there a better suggestion? Also, what height should I be filling to? Thanks in advance!

[betoney]

Send K-Tech an email or give them a call, they will tell you what they recommend for their product. 

[littlebruv]

Hi NotVeryCreative16

10 grade fully synthetic fork oil, best you can afford and as you weigh 250 lbs in bike gear K-Tech 10NM fork springs, these are what i got as i weigh about the same as you, the transformation on the front end is excellent.

If not too sure concerning about the fork oil watch the preview of Dave Moss on Youtube about MT09 suspension

Edited October 28, 2020 by littlebruv

[NotVeryCreative16]

4 hours ago, betoney said:

Send K-Tech an email or give them a call, they will tell you what they recommend for their product. 

Fair enough. Email sent.

2 hours ago, littlebruv said:

Hi NotVeryCreative16

10 grade fully synthetic fork oil, best you can afford and as you weigh 250 lbs in bike gear K-Tech 10NM fork springs, these are what i got as i weigh about the same as you, the transformation on the front end is excellent.

If not too sure concerning about the fork oil watch the preview of Dave Moss on Youtube about MT09 suspension

How much do you weigh exactly? You don't think the 10 NM springs were too stiff? I went back and forth between the 9.5 and 10 but now I'm second guessing myself.

[betoney]

6 hours ago, NotVeryCreative16 said:

I pulled the trigger on some K-Tech 20IDS cartridges to match my Razor shock. Now I just need to confirm what fork oil to go with and what height I should be filling to. I weigh 250 lbs with gear and went with the 9.5 NM spring. I've done so much reading that my brain hurts but I'm still confused. Should I be looking for an oil that is approximately 16cSt@40? I think that's what I've gathered from my reading. It seems like the Maxima 5W racing fork oil matches that specification. Will that work is there a better suggestion? Also, what height should I be filling to? Thanks in advance!

Find a brand you like and stick with that brand for consistency because not every 5w fork oil is the same.  You can 'fine tune' your fork feel with different weight oil, though that is mostly done with non-adjustable damping, it can be beneficial for the non-adjustable high speed circuit. The fork internals are basic hydraulics, thicker fluid (higher viscosity) moves slower through a given valve orifice and thinner fluid moves faster.  If you use Maxima 5w and find it is too thin, you can start going higher 7.5w, 10w etc. 

As a general rule, several tuners recommend a fluid height from 150mm up to 120mm from the top (fully compressed with out springs).  When I get mine serviced, I believe the tech sets the oil height around 150mm-140mm from the top.  Hope that helps.

[NotVeryCreative16]

1 hour ago, betoney said:

Find a brand you like and stick with that brand for consistency because not every 5w fork oil is the same.  You can 'fine tune' your fork feel with different weight oil, though that is mostly done with non-adjustable damping, it can be beneficial for the non-adjustable high speed circuit. The fork internals are basic hydraulics, thicker fluid (higher viscosity) moves slower through a given valve orifice and thinner fluid moves faster.  If you use Maxima 5w and find it is too thin, you can start going higher 7.5w, 10w etc. 

As a general rule, several tuners recommend a fluid height from 150mm up to 120mm from the top (fully compressed with out springs).  When I get mine serviced, I believe the tech sets the oil height around 150mm-140mm from the top.  Hope that helps.

All solid advice, thanks.

[littlebruv]

7 hours ago, NotVeryCreative16 said:

Fair enough. Email sent.

How much do you weigh exactly? You don't think the 10 NM springs were too stiff? I went back and forth between the 9.5 and 10 but now I'm second guessing myself.

I weigh 260lbs, the oil i used motul 10 grade 100% fully synthetic with the K-Tech 10nm springs now run in and suspension as been re checked and set up for me by a KTM technician works perfect giving a much better feel on the front end especially at high corner speeds. 

Edited October 29, 2020 by littlebruv

[betoney]

 

19 hours ago, NotVeryCreative16 said:

I weigh 250 lbs with gear and went with the 9.5 NM spring

 

14 hours ago, NotVeryCreative16 said:

How much do you weigh exactly? You don't think the 10 NM springs were too stiff? I went back and forth between the 9.5 and 10 but now I'm second guessing myself.

FWIW, I weigh 215lbs w/o riding gear and use .95nm springs with very little preload, the springs 'should' be fine for you as you can add preload to get your sag set if needed. 

After you have your sag set, make sure to use the zip tie on the fork leg and ride a route with some aggressive cornering and stopping to check your fork travel.

[Salish900]

I really appreciate this thread because like @NotVeryCreative16 I've been reading a lot and learning. I'm 210 lbs with my gear and will sometimes ride with my wife, so I went with KTech 9.5nm and after reading the fluid chart you can find linked to here, went with Motul 7.5W full synthetic. It's a little more viscous than stock, and I'll give it a try. I've done the fork oil on my Connie springs, but it's been a while. I have a compressor. 

My main question has been the setting of the oil height, and I'm still a little fuzzy on how precisely to do that, but there are videos. Thanks so much for the passing along of lessons learned! My front end dives so much when I brake hard, even with my preload bottomed out, and my sag is still 50. Crazy how weak these stock springs are.

[littlebruv]

10 hours ago, littlebruv said:

I weigh 260lbs, the oil i used motul 10 grade 100% fully synthetic with the K-Tech 10nm springs now run in and suspension as been re checked and set up for me by a KTM technician works perfect giving a much better feel on the front end especially at high corner speeds. 

I suppose it also all depends how aggressive you ride with the front end

[kimmie]

Had my 2015 for 5 years now. We did a fork upgrade at about 5000km. Replaced the fork oil with 2.5w Motorex fork oil yesterday at 99,906km and must say it was pretty yuk and stank like sewerage. Rest of the 100,000km service done too including re-gassing the ZX6R rear shock and replaced and realigned the Tutora oiler.

Ready for the a test run this afternoon and the next 100,000km's.

 

I'm in Australia and this is the oil weight that was recommended by Pattonme.

A bit late for the info but hope it helps.

 

[littlebruv]

 

[Yamajank]

What weight oil comes stock on 2019 GT?

 

[littlebruv]

5 usually

 

Edited November 16, 2020 by littlebruv

[vancuy]

On 11/16/2020 at 6:56 PM, kimmie said:

Had my 2015 for 5 years now. We did a fork upgrade at about 5000km. Replaced the fork oil with 2.5w Motorex fork oil yesterday at 99,906km and must say it was pretty yuk and stank like sewerage. Rest of the 100,000km service done too including re-gassing the ZX6R rear shock and replaced and realigned the Tutora oiler.

Ready for the a test run this afternoon and the next 100,000km's.

 

I'm in Australia and this is the oil weight that was recommended by Pattonme.

A bit late for the info but hope it helps.

 

Hi Mate,
what was your fork upgrade? I just purchased 2015 Tracer with 19k kms. I 'd like to hear about your experience. 
I can only afford springs and oil.