2018 Honda NC750XD Showa Dual Bending Valve (SDBV) forks oil

[Sparrowwheels 0]

Hello.

I Have a 2018 Honda NC750XD with 41mm Showa Dual Bending Valve (SDBV) forks!

What amount of oil should be in each fork? How many millimeters should the air gap?

I was found a information: 517ml (+-2.5ml). But in this manual (Honda NC750X 2017) is different fork...

I try 517ml, but then air gap is about 90mm

 

p.s.

when I drained the old oil, the amount was about 500ml...

Edited May 3, 2023 by Sparrowwheels

[Viator 1,526]

Hi @Sparrowwheels, welcome to the forum. I can't answer your question directly but I learned when changing the springs in my 2022 model that the oil/air gap is measured with the springs out, I had initially measured with them in and it had raised the level by 40mm. If that is the case with your 90mm air gap the the measurement will probably be around 130 without the springs.

[Sparrowwheels 0]

8 minutes ago, Viator said:

Hi @Sparrowwheels, welcome to the forum. I can't answer your question directly but I learned when changing the springs in my 2022 model that the oil/air gap is measured with the springs out, I had initially measured with them in and it had raised the level by 40mm. If that is the case with your 90mm air gap the the measurement will probably be around 130 without the springs.

 

Thank you.
I measured without springs as written in the 2017 service manual...
I have written to HONDA support, but have not received a reply from local dealer.

 

[MatBin 5,097]

You will need an open ended spanner as there isn't a socket that fits the shape of the nut that any of us can find. I got my spanner from the auction site, open ended plus ring.

Air gap is measured with forks off the bike, spring out and forks at full length. There are various heights quoted depending on model year, so I measured mine, which didn't seem to line up with any recommendations, so I just put in what I believed was the correct amount of new fluid after drawing the old stuff(I posted it somewhere on here) and they seem ok, less jarry by the time they have warmed up and just about acceptable. I think I put in just under 500ml per leg, searched previous thread for an answer and it was 430ml with 140mm air gap. The amount is very hit and miss based on fluid viscosity, rider weight, how you like your forks etc, so you may have to experiment, I think I just got lucky first time. To measure mine I literally just put a wooden dowel down the inside of the leg till it touched the fluid.

Edited May 3, 2023 by MatBin

[Sparrowwheels 0]

9 minutes ago, MatBin said:

You will need an open ended spanner as there isn't a socket that fits the shape of the nut that any of us can find. I got my spanner from the auction site, open ended plus ring.

Air gap is measured with forks off the bike, spring out and forks at full length. There are various heights quoted depending on model year, so I measured mine, which didn't seem to line up with any recommendations, so I just put in what I believed was the correct amount of new fluid after drawing the old stuff(I posted it somewhere on here) and they seem ok, less jarry by the time they have warmed up and just about acceptable. I think I put in just under 500ml per leg, searched previous thread for an answer and it was 430ml with 140mm air gap. The amount is very hit and miss based on fluid viscosity, rider weight, how you like your forks etc, so you may have to experiment, I think I just got lucky first time. To measure mine I literally just put a wooden dowel down the inside of the leg till it touched the fluid.

Thanks for the reply. I understand that the amount of 517ml is not correct for this fork

[MatBin 5,097]

3 minutes ago, Sparrowwheels said:

Thanks for the reply. I understand that the amount of 517ml is not correct for this fork

Tbh 517/500 isn't going to make much difference to what are very basic forks that arent the best in the world anyway. I see you are in Latvia, I hope your roads are better than UK ones, ours are absolutely awful, full of potholes.

Edited May 3, 2023 by MatBin

[Sparrowwheels 0]

7 minutes ago, MatBin said:

 I see you are in Latvia, I hope your roads are better than UK ones, ours are absolutely awful, full of potholes.

We have similar ones, but are generally good for driving.

[skorpion 945]

5 hours ago, Sparrowwheels said:

Hello.

I Have a 2018 Honda NC750XD with 41mm Showa Dual Bending Valve (SDBV) forks!

What amount of oil should be in each fork? How many millimeters should the air gap?

I was found a information: 517ml (+-2.5ml). But in this manual (Honda NC750X 2017) is different fork...

I try 517ml, but then air gap is about 90mm

 

p.s.

when I drained the old oil, the amount was about 500ml...

 

In the UK SDBV air gap 180mm, but others have found anything down to 130mm works for them.

[Sparrowwheels 0]

Thank you everyone for your answers and help!

I spoke to several Honda dealers (Latvia, USA, Italia, UK, Estonia) and asked for help regarding this issue.

Only the Estonian Honda dealer responded kindly and provided all the necessary information! I would share that information, but I can't put a picture in this forum.

https://drive.google.com/file/d/1ZQcDKlyH_PzgQR6HZzVseV4lMRxFdr_T/view?usp=sharing

https://drive.google.com/file/d/14Gj0IoQwFkPOs-ykXy1PSKjerZVXElgO/view?usp=sharing

I was unpleasantly surprised by the attitude of the Honda dealers in our region. In response to my question, I was advised to approach a local dealer (which isn't answering).

Thanks to the  Estonian Honda dealers in the Baltic states!

 

p.s. My air gap is 180mm!

Edited May 5, 2023 by Sparrowwheels

[ChrisCB 6,674]