Fork oil brand and weight question

[FADEC]

Looking to change out the fork oil this fall on my 2009 Harley Fat Bob. I've owned it since last fall and it's always had ALOT of fork dive on light to moderate braking.

I believe it's on its original fork oil, which from what I understand, is a 10 weight.

Looking to go with a 15 or possibly a 20 weight oil. I come from sport bikes so I like firm forks.

What brand?? I have used BelRay products before with great results. What about Motul, Silkolene, or others?

On this bike you have to actually remove the forks from the triple trees, invert them to drain then refill and reinstall. Pain!!

 

[Hermann]

thicker fork oil will help a bit, at the expense of a harsher ride. The real solution is a set of Progressive Suspension springs, will cost about a $100 for the springs but it will solve your problem.

 

[Mackelroy]

Well Ive had a few bikes rated for 5 weight oil and installed 15 weight and luved the compression. Course without rebound adjustment, which will be effected also, thats the Big question.

But on a street bike, bigg successive hits are not much an issue, the only thing, you do need to drop oil height about 5 to 10 mm, with a Heavier fluid. Or else you might see hydraulic lock towards the bottoming of the stroke.

Staying with the stock fluid, and increasing oil height 5 to 10mm will also have a similar effect. Get an oral suringe and add 5cc to each leg before you change the fluid, just to see the effect. You can do this one leg at a time by removing the fork cap on just one leg and adding fluid, reinstall the cap and do the other leg, you have to let the front wheel on the ground to seperate the cap, wheel off the ground to reinstall the cap.

 

[BigCahuna]

Harley used to sell two types of fork oil. The regular type for most bikes, and their version of hight performance fork oil. I bought their regular oil a few years back for my '96 cop bike. It looked and smelled just like ATF. It cost about $8.00 for a small bottle. If I had known that was what it was, I would have bought a qt at the auto store for Less then $3 a qt.My old Goldwing used ATF in the forks and the shocks. Worked as good as the Harley stuff. ,,

 

[FADEC]

I would not be opposed to using ATF in my forks. I just need to be sure its viscosity is at least 15w.

 

[marc1]

Originally Posted By: daddi

What brand?? I have used BelRay products before with great results. What about Motul, Silkolene, or others?



I can't help you with the weight, I have never owned a street bike and am unsure of the best weight for you, I have only owned dirt bikes. What I can recommend is a brand of fork oil and that is Redline, I have used them with excellent results (no fade / foaming etc.). They have wide availability, wide viscosity range choices and are a good price.

 

[FADEC]

Originally Posted By: marc1
Originally Posted By: daddi

What brand?? I have used BelRay products before with great results. What about Motul, Silkolene, or others?



I can't help you with the weight, I have never owned a street bike and am unsure of the best weight for you, I have only owned dirt bikes. What I can recommend is a brand of fork oil and that is Redline, I have used them with excellent results (no fade / foaming etc.). They have wide availability, wide viscosity range choices and are a good price.


Love Redline oils......Didn't realize they made a fork oil.

 

[marc1]

For sure, check it out:

http://www.redlineoil.com/Products.aspx?pcid=18

I also use their 2 stroke racing oil exclusively (not applicable to you of course). I mix the ratio (numerically higher) much lower than I would using conventional oils so less smoke, better performance etc.

 

[Ken2]

Quote:
A LOT of fork dive on light to moderate braking.
Here are two good solutions to do it right.

First, put in new springs that match your riding weight.
http://www.sonicsprings.com/catalog/calc...5ea5e902f0c863f
http://www.sonicsprings.com/catalog/straight_vs_prog_tech_article.php
If Sonic Springs doesn't have a listing for your bike, ask. Rich is very responsive and knows a lot about suspension.

Second, improve the damping with Ricor Intiminator damping valves:
http://store.ricorshocks.com/FAQ_s/41.htm
http://store.ricorshocks.com/category_s/63.htm

 

[Mik]

Here you go:
http://transmoto.com.au/Comparative-Oil-Weights-Table

 

[Mackelroy]

I guess they didnt fiqure Harley oils were worth mentioning. I did like the table though, it confirmed what I knew utilizing one brand to the other of the same weight, it aint the same. >G<

 

[greenjp]

I've never understood the interest in using something other than fork oil in motorcycle forks. I've seen it discussed on every board I've participated in, and for the life of me I can't figure it out. Proper fork oil is
jeff

 

[Hermann]

Originally Posted By: greenjp
I've never understood the interest in using something other than fork oil in motorcycle forks. I've seen it discussed on every board I've participated in, and for the life of me I can't figure it out. Proper fork oil is div>


Proper fork oil was $7.xx a couple months age at the BMW dealer for their brand. It is 15wt