Fork Oil Substitutes

[84xj1100]

Put in an order for the progressive fork springs...there on the way...one of the boys here at work mentioned the use of Dextron VI (transmission fluid) in lieu of 10wt fork oil.

 

I took a peek on my greatest reference tool (this site) and found little info on the subject. It would appear that some folks have done it but I'm just wondering what the ramifications, if any, there are or would be.

 

Plse chime in......

[GaryZ]

This is a timely question . . .

 

I have a new set of Progressive springs waiting to go in!

[MiCarl]

DEXTRON II has a viscosity of 5W20. It'll give you less damping than 10W fork oil.

 

ATF has a high detergent level, where fork oil does not have detergents. Doubt if the detergent would cause a problem but.......

 

You're looking at less than $20 worth of fork oil. Why risk not being satisfied with the results?

[Rocket]

DEXTRON II has a viscosity of 5W20. It'll give you less damping than 10W fork oil.

 

ATF has a high detergent level, where fork oil does not have detergents. Doubt if the detergent would cause a problem but.......

 

You're looking at less than $20 worth of fork oil. Why risk not being satisfied with the results?

 

Also Progressive Suspension was previously known, to recommend using 15W fork oil. Not sure if that is still the same or not, these days.

[Karl C.]

It seems as if I read somewhere else also that if you redoing your front forks and if they are new you may wish to stay with a 10 wt... but if your bike has miles/front forks are a little worn you may want to use 15 wt. I personally am going to use 15 wt...

[hi-plainsdrifter]

I have been using 15 wt and it rides great!

[84xj1100]

Thanks so much, as always folks, for your input. I plan on tackling the job this weekend so if anyone else wants to chime in feel free. If anyone has any tips, tricks or hints I'm all ears (so to speak)

[warthogcrewchief]

I heard from a venture owner/Yamaha dealer that he used full Synthetic Valvoline motor oil. I tried it out when I installed my Progressive forks. They work well, are a little stiff, but still rides extremely well. I think it was the 5w-20 or the 10w-30....I forget which viscosity I used.

 

BTW, I fixed almost everything including the forks before I rode it, so I don't have a before/after comparison. I have no complaints from this setup! The important part is to ensure you have equal measurements in both forks (get them as equal as possible) or you could have uneven forks which can lead to a plethora of issues!

[pegscraper]

Motor oil in the forks may feel fine at first but will not last long. It will break down and the forks will be very soft. Motor oil is not designed to stand up in that kind of application.

[84xj1100]

WOW what a difference!!!!!

 

I had no idea the old ones (original from what I can gather from the forum) were in such rough shape. It almost feels like power steering or something........the front end is higher/seat height is noticably different at a stop, not to mention the fact that when I dismount it feels like an ejection seat. I ended up putting 15wt fork oil in with appox 5psi. When I put her back together, I used about 1/4" of the spacer provided and even at that it was quite a feat getting that plug back in.

 

Thank you all for your input as well as this forum (once again) for the help, advise and being such a magnificent reference source.

[puppy]

Any recommendations for progressive springs? I have been looking at this next, have not searched around much. But, followed this thread. Who did you get your springs through?

[rjg1985]

http://www.mawonline.com/newsite/progressive-fork_springs.htm

 

This is were I bought mine from, good price and fast shipping.

Here is the part #: Progressive Fork Springs Pair 45/70 #111112

[jeff1]

Per Rick at Buckeye Performance I used 10w30 synthetic motor oil with my Progressive springs. He told me that this choice has better lubricating qualities than fork oil and being synthetic it should hold up well. The springs and oil along with a heavy duty fork brace transformed the handling of my '89.

[jasonm.]

DEXTRON II has a viscosity of 5W20. It'll give you less damping than 10W fork oil.

 

ATF has a high detergent level, where fork oil does not have detergents. Doubt if the detergent would cause a problem but.......

 

You're looking at less than $20 worth of fork oil. Why risk not being satisfied with the results?

 

I disagree on 5w20 being less than 10wt. I use 5w20 mobil 1 in my forks. I did a flow test. Because that's how dampers work, restricting flow. 5w20 is actually slightly thicker than 10wt. but less than 15wt. 0w20 is same as 10wt. trust me on this. AND using a 10w30...wow that is usually WAY stiff. As my testing and riding showed 0w30 and 5w30 also too stiff for my 190# self. Which I did try years ago. As far are similarities to Dextron...I really do not know. But the above is many hours of testing on a flow bench thru orifaces.