5W or 10W fork oil

Supertee123

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Aug 13, 2015
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85
Location
Dublin Ireland
Any recommendations what weight oil to use,I know OEM is close to a 5W but over time viscosity will drop so would I be better off on a 10W oil,I ride in road,any thoughts on this .
Thanks folks.
 

RCinNC

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This is what I've used for every fork service. I can't make any claims that it's the best, or better than any particular other brand, but it's worked fine for me for many miles of combination road/dirt/gravel.

Spectro.jpg
 

~TABASCO~

RIDE ON ADV is what I do !
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Any recommendations what weight oil to use,I know OEM is close to a 5W but over time viscosity will drop so would I be better off on a 10W oil,I ride in road,any thoughts on this .
Thanks folks.

1) What do you weigh ?
2) Is the valve stack stock ?
3) Are the forks totally stock ?
4) How many miles (Km) on your stock springs?
5) In the past have you found the front end to be soft / great / firm ?
6) How many miles (Km) between your fork oil changes?

Also dont forget you can get different ride characteristics not only with the weight of the oil but the + or - in oil volume and the air chamber left in the top of the fork. This aspect will also hinge on how specific and exacting someone is with this "volume".

IMOP, With 37 years motorcycle service experience, I suggest that you not just throw the volume of oil a manufacture tells you to use and ride down the road. What I mean is, if a manufacture tells you that a fork holds XXXXX oil, dont just measure this out, pour it in, put the top cap on and go ride. What I would suggest is the XXXXX is a really good starting point. Work this in and get all the air and 'froth' out of the oil once its in the leg. Then measure the volume. 99% it wont be correct, sometimes is WAY off. Then dial in if you want stock height or you would like to change the performance a little by adding or taking a bit of volume in / out.

For example, the last time I tore down my forks to clean, re fresh, and oil change I worked for several hours to get all the air out of the rebound side of the fork. After this period of time I was 99% I had all the air out. I let it sit over night to rest. The next day I checked it again and spent maybe 30 minutes with this same fork and I did get a few more small bubbles out. After all this I was able to use the proper tools to check and re check the volume. If I had not worked on getting all this air out the oil volume would have been way off... (going back to the settings I made notes of would have been way off... it would have been wrong and the ride characteristics would have been screwed up.)
 

gv550

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Sep 14, 2016
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Listowel, Ontario, Canada
I’ve tried several different brands and viscosity, and found this works best with stock damping components.
KYB 01m, same as Yamaha fork oil. Not surprising since the bike uses KYB (Kayaba) forks.
AD22D477-E65B-45D0-88E2-FD8D5683DEEF.jpeg
 

escapefjrtist

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Sep 5, 2010
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Snohomish WA
Neither. Here’s a link to a good explanation on fork oil. I followed things the best I could with Redline oil and got good results on my 2014 non-es. Towards the bottom it lists various manufacturers and their wt.

This ^^^^ Forget about 5W or 10W oil, use the viscosity that best matches the OE suspension fluid.

~G
 

jrusell

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Aug 23, 2017
Messages
460
Location
Dartmouth, Nova Scotia, Canada
With many bikes in the past I found going up to 10Wt was a good option to get a bit more damping.
I did this with my Tenere with the first fork oil change. Immediately I found the fork more harsh on small road irregularities. I switched back to 5wt and it went back to normal.

When I revalved the fork and had the stock pistons out of the cartridge I understood why I got that feeling. Stock Compression piston ports are extremely small. If you look back through some of my older posts there are pics of the stock pistons. Thicker weight oil and the stock pistons made the fork very harsh. What I mean is I could feel every little ripple in the surface if the road wad bumpy.

I would recommend to stay with 5wt and service your forks regularly.
 

Supertee123

Member
Joined
Aug 13, 2015
Messages
85
Location
Dublin Ireland
1) What do you weigh ?
2) Is the valve stack stock ?
3) Are the forks totally stock ?
4) How many miles (Km) on your stock springs?
5) In the past have you found the front end to be soft / great / firm ?
6) How many miles (Km) between your fork oil changes?

Also dont forget you can get different ride characteristics not only with the weight of the oil but the + or - in oil volume and the air chamber left in the top of the fork. This aspect will also hinge on how specific and exacting someone is with this "volume".

IMOP, With 37 years motorcycle service experience, I suggest that you not just throw the volume of oil a manufacture tells you to use and ride down the road. What I mean is, if a manufacture tells you that a fork holds XXXXX oil, dont just measure this out, pour it in, put the top cap on and go ride. What I would suggest is the XXXXX is a really good starting point. Work this in and get all the air and 'froth' out of the oil once its in the leg. Then measure the volume. 99% it wont be correct, sometimes is WAY off. Then dial in if you want stock height or you would like to change the performance a little by adding or taking a bit of volume in / out.

For example, the last time I tore down my forks to clean, re fresh, and oil change I worked for several hours to get all the air out of the rebound side of the fork. After this period of time I was 99% I had all the air out. I let it sit over night to rest. The next day I checked it again and spent maybe 30 minutes with this same fork and I did get a few more small bubbles out. After all this I was able to use the proper tools to check and re check the volume. If I had not worked on getting all this air out the oil volume would have been way off... (going back to the settings I made notes of would have been way off... it would have been wrong and the ride characteristics would have been screwed up.)
Hi Tabasco
1) What do you weigh ?
2) Is the valve stack stock ?
3) Are the forks totally stock ?
4) How many miles (Km) on your stock springs?
5) In the past have you found the front end to be soft / great / firm ?
6) How many miles (Km) between your fork oil changes?

Also dont forget you can get different ride characteristics not only with the weight of the oil but the + or - in oil volume and the air chamber left in the top of the fork. This aspect will also hinge on how specific and exacting someone is with this "volume".

IMOP, With 37 years motorcycle service experience, I suggest that you not just throw the volume of oil a manufacture tells you to use and ride down the road. What I mean is, if a manufacture tells you that a fork holds XXXXX oil, dont just measure this out, pour it in, put the top cap on and go ride. What I would suggest is the XXXXX is a really good starting point. Work this in and get all the air and 'froth' out of the oil once its in the leg. Then measure the volume. 99% it wont be correct, sometimes is WAY off. Then dial in if you want stock height or you would like to change the performance a little by adding or taking a bit of volume in / out.

For example, the last time I tore down my forks to clean, re fresh, and oil change I worked for several hours to get all the air out of the rebound side of the fork. After this period of time I was 99% I had all the air out. I let it sit over night to rest. The next day I checked it again and spent maybe 30 minutes with this same fork and I did get a few more small bubbles out. After all this I was able to use the proper tools to check and re check the volume. If I had not worked on getting all this air out the oil volume would have been way off... (going back to the settings I made notes of would have been way off... it would have been wrong and the ride characteristics would have been screwed up.)
Tabasco front and rear suspension is OEM standard,this will be my second fork rebuild from 80000km now 125000km so well overdue.
 
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