Cheapo fork oil, pros if any?

[Nessism]

There is so much more to fork oil than viscosity.

You are forgetting about anti foam, and anti corosion protection that must be higher than that of motor oil and compressor oils. It may work at first and for a while, but you're risking long term damage to the inner workings and possible catostrofic failure of damping in the case of a foamup. If it foams and air gets permiated through the oil, dampening can disapear all together. Something you won't find out until it's too late. High speeds on choppy pavement will find you riding a pogo stick for a front suspension.

Really, is that risk worth saving a few bucks for?

The best tires in the world won't help you turn, accelerate, or stop, if you can't keep the tires in good contact with the pavement. That's the job of the suspesion and ultimately the fork/shock oil. It's not just how it feels on a Sunday ride or bouncing it in the garage.

If motor oil and ATF are so bad than how come Suzuki recommends it in the service manual? And what evidence do we have that motor oil has less "anti foam" additives than fork oil? Honestly now, I'm not against using fork oil but I'm just not convinced that it's all that much different than motor oil other than the available viscosity range is better

[GSexpress]

If motor oil and ATF are so bad than how come Suzuki recommends it in the service manual? And what evidence do we have that motor oil has less "anti foam" additives than fork oil? Honestly now, I'm not against using fork oil but I'm just not convinced that it's all that much different than motor oil other than the available viscosity range is better

I didn't include ATF. It's a much better choice than motor oil. All you have to do is look up the SAE standards to see how much anti foam requirements are for different oil types.

If there weren't a good reason for using it, I don't think a manufacturer would spend the money on it to put it in the bike in the first place.

But I guess you're smarter than they are.

[Nessism]

I didn't include ATF. It's a much better choice than motor oil. All you have to do is look up the SAE standards to see how much anti foam requirements are for different oil types.

If there weren't a good reason for using it, I don't think a manufacturer would spend the money on it to put it in the bike in the first place.

But I guess you're smarter than they are.

In the GS850 and GS1000 manuals Suzuki calls for SAE 10W/20 oil.

The GS550 and GS750 manuals states half and half SAE 10W-30 and ATF

Use fork oil if you want, I do, but it wouldn't bother me to use motor oil and/or with ATF, and other folks shouldn't either assuming they trust Suzuki's recommendation.

[makenzie71]

Modern motor oils have a lot more in them to keep them from foaming up than modern fork oils...as well anti corrosion compounds. If anything, with motor oil, you get way too much OTHER crap...not the other way around. If you get motor oil to "foam" up in your forks you have some serious issues not at all related to the oil.

On top of that, if you change your oil every year...minimum...like you're supposed to do...you'll never see any of the anti corrosion or other spiffy "features" of either at work.

The worst thing you'll see with motor oil is from the variable weight stuff when really working the suspension hard. I run Rotella 15-40 in my bike from one end to the other...shocks, motor, forks...and when I'm really working the shocks they'll stiffen up noticeably. When I go back and change all my fluids I'll be running a straight 20w something.

[Furious D]

I've used ATF or Automatic tranny fluid for years in my "older" bikes. Its pretty cheap and is about 10W depending on the brand.


I was turned on to this by and old bike mechanic. He claimed the ATF would cure oil leaks about 50% of the time. I did notice it did slow down a leak in an old BMW I had.

[duaneage]

I get at least 2 changes from a 9 dollar quart of fork oil. Surely there are other ways to save money.

[rustybronco]

In the GS850 and GS1000 manuals Suzuki calls for SAE 10W/20 oil.

The GS550 and GS750 manuals states half and half SAE 10W-30 and ATF

Use fork oil if you want, I do, but it wouldn't bother me to use motor oil and/or with ATF, and other folks shouldn't either assuming they trust Suzuki's recommendation.

I've been using a 50/50 blend of dexronIII AFT and straight 20 wt engine oil for around 4 years now with no adverse effects. very easy to calculate the final weight of the 'fluid' using 8 wt as the value for ATF and 20 wt for the motor oil.

[salty_monk]

The W in engine oil is different to that in fork oil....

5w30 is approx eq to 20w fork oil. ATF fluid is about 10-12w.

No problems with use of either in forks from research I have done.

[mike_of_bbg]

My last bottle of fork oil cost less than $0. I used it as filler when I ordered my tire to get above the free shipping value

[rustybronco]

ATF fluid is about 10-12w.

I guess you and I will just have to differ...

[Nessism]

Some good oil viscosity info here... http://www.peterverdonedesigns.com/lowspeed.htm

[Ranger]

Thanks Ed, I think I'll attempt to switch my seals out. You think they're cheaper off Z1 or at a suzuki shop? Dumb question I know.

[Nessism]

Thanks Ed, I think I'll attempt to switch my seals out. You think they're cheaper off Z1 or at a suzuki shop? Dumb question I know.

Hope you aren't going to wait for me to look up the prices when you are just a few clicks away from the answer of your own accord.

BTW, Z1's K&L fork seals are dirt cheap...and are sure to beat the Suzuki seals in terms of price by a large margin. Quality is another matter though...

[salty_monk]

I have Z1's seals on my 1000g, had about 15,000 miles on them last time I saw that bike....

In general stock seem to be better than K&L anything though!

I pulled my info from the web a while back but I'm definitely willing to be corrected, I didn't spend a lot of time on it... personally I use fork oil, life is too short!