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Old Apr 30, 2023 | 11:36 AM
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Default Fork oil
Anyone use 5w-20 in their old school forks (39mm, late-90s vintage)? If so, what are your results? (I've got a lot of 5w-20 on the shelf and would rather avoid a trip to the dealership, where I will inevitably spend way more than I intend).
 
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Old Apr 30, 2023 | 12:02 PM
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Originally Posted by Lars_Danner
Anyone use 5w-20 in their old school forks (39mm, late-90s vintage)? If so, what are your results? (I've got a lot of 5w-20 on the shelf and would rather avoid a trip to the dealership, where I will inevitably spend way more than I intend).

I wouldn't.....

Fork oil weights and engine oil weights are measured differently. They are not the same... 20W engine oil is not the same as 20W fork oil..

Additionally, fork oil has anti-foaming additives in it....

IMHO... It may work, but I'm confident it wouldn't perform the same, or as well as fork oil...
 
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Old Apr 30, 2023 | 04:04 PM
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Originally Posted by Lars_Danner
Anyone use 5w-20 in their old school forks (39mm, late-90s vintage)? If so, what are your results? (I've got a lot of 5w-20 on the shelf and would rather avoid a trip to the dealership, where I will inevitably spend way more than I intend).
I’ve gotta pick up some 20wt fork oil myself, I can pick you up some…
 
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Old Apr 30, 2023 | 05:51 PM
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Originally Posted by Mongo7
I’ve gotta pick up some 20wt fork oil myself, I can pick you up some…
Too late, I already put in the 5w20.
 
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Old Apr 30, 2023 | 06:13 PM
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Originally Posted by Lars_Danner
Too late, I already put in the 5w20.

Let us know how it performs.....
 
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Old Apr 30, 2023 | 06:51 PM
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Originally Posted by hattitude
Let us know how it performs.....
I went for a short ride around the block seemed okay. I'll do some more riding next week and report back. My guess is it'll be just fine.
 
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Old May 29, 2023 | 03:25 PM
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Originally Posted by Lars_Danner
I went for a short ride around the block seemed okay. I'll do some more riding next week and report back. My guess is it'll be just fine.
So I've ridden about 100 mi over various road conditions with 5w20 as fork oil. It seems to work fine.
 
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Old May 29, 2023 | 03:43 PM
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it is fine,
 
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Old Jun 7, 2023 | 10:11 AM
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Originally Posted by Lars_Danner
So I've ridden about 100 mi over various road conditions with 5w20 as fork oil. It seems to work fine.
Cool.
It would be interesting to know what the long term performance would be like.
 
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