After hearing that clutch manufacturer Barnett recommends using ATF with their clutches and reading posts about Harley owners with experience using ATF in their primaries I changed the Fluid in my Deuce's primary today. Used Castrol ATF+4. Shifting was quite noticeably smoother.
Switched to ATF in the Primary
- Thread starter rn2fine
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ATF is probably in the 15 to 20 weight range. Formula+ is in the 40 to 50 weight range. One of the resaons that some of the aftermarket clutch manufacturers recommend ATF is that it's thinner and provides for a more positive clutch engagement.
Keep an eye on your chain tensioner shoe for signs of wear. Other than that, it's probably just fine.
Personally, I've used Rotella or Delvac 15W40 for years and years. Although the Delvac seems to provide a fuzz smoother shifting.
I've tried the ATF but (if I remember correctly) the "smooth shifting" seems to go south around 1500 miles. Would be interested to hear from you and your experience, once you have a few miles on the change.
Thanks
Kevin
Keep an eye on your chain tensioner shoe for signs of wear. Other than that, it's probably just fine.
Personally, I've used Rotella or Delvac 15W40 for years and years. Although the Delvac seems to provide a fuzz smoother shifting.
I've tried the ATF but (if I remember correctly) the "smooth shifting" seems to go south around 1500 miles. Would be interested to hear from you and your experience, once you have a few miles on the change.
Thanks
Kevin
Kballowe make a very good point you want to keep an eye on your chain tensioner shoes for wear. Also you have a compensator in the primary that needs oil to cushion between the springs. So if you start see a lot fine metal on your drain plug it is most likely coming from there.
I know a lot of guy that use "B&M Trick Shift" and are happy.
Every time I tried it, I ended up going back to Motorcraft or Rotella diesel oil 15w-40.
I know a lot of guy that use "B&M Trick Shift" and are happy.
Every time I tried it, I ended up going back to Motorcraft or Rotella diesel oil 15w-40.
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Most ATF's are in the 7-7.5 Cst range. Much lower than what's generally seen with even a xW-20.
GM's Dexron-VI is even a bit lighter than this.
Many years ago when I raced 125cc and 250cc two-stroke motocross bikes, I'd use ATF in their gear boxes. I never experienced a lubrication failure.
GM's Dexron-VI is even a bit lighter than this.
Many years ago when I raced 125cc and 250cc two-stroke motocross bikes, I'd use ATF in their gear boxes. I never experienced a lubrication failure.
Originally Posted By: FowVay
Most ATF's are in the 7-7.5 Cst range. Much lower than what's generally seen with even a xW-20.
GM's Dexron-VI is even a bit lighter than this.
Many years ago when I raced 125cc and 250cc two-stroke motocross bikes, I'd use ATF in their gear boxes. I never experienced a lubrication failure.
What am I missing? I thought that 7 Cst was right in the middle of the 20 wt range. At least it is on this chart
Viscosity chart
.
BTW that Castrol ATF+4 is 7.5
.
Most ATF's are in the 7-7.5 Cst range. Much lower than what's generally seen with even a xW-20.
GM's Dexron-VI is even a bit lighter than this.
Many years ago when I raced 125cc and 250cc two-stroke motocross bikes, I'd use ATF in their gear boxes. I never experienced a lubrication failure.
What am I missing? I thought that 7 Cst was right in the middle of the 20 wt range. At least it is on this chart
Viscosity chart
.
BTW that Castrol ATF+4 is 7.5
.
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Being there is more then just clutch plates in a Harley's primary case, I was wondering if ATF provides suffecient lubrication for the chain, gear teeth, the plastic chain tensioner, and if it has any negative effect on the bikes stator.Being that Harley recommends oil for that particular compartment of the bike.I don't believe you need to use Harleys oil for everything on the bike, but ATF seems to be way off the chart of acceptable alternatives.,
I tried several different oils in the primary of my '07 EGC; Redline MTL, Syn3, Formula+, Amsoil 20W-50, and Rotella 15W-40. Of them all I liked Formula+ best, so I used it for 15k miles and on my last change switched to Rotella, as it gives nearly identical clutch feel, has a better add pack, and costs about 75% less.
As for ATF, as a mechanic I wouldn't be comfortable using a 20W oil in a 50W GL3 environment. I know lots of folks use it and swear by it, but I'm not willing to bet my primary on someone else's success. Kinda like motor oil; when someone recommends "Brand A" oil to somebody because they've "Been using it for 20k miles with no problems", that means nothing to me. I assume by "no problems" they mean the engine hasn't seized or blown up; heck I know of quite a few cars that have over 100k miles on them using no-name dime store oil bought on clearance and have not had any such "problems."
But that doesn't mean I'm gonna run it in my equipment...
As for ATF, as a mechanic I wouldn't be comfortable using a 20W oil in a 50W GL3 environment. I know lots of folks use it and swear by it, but I'm not willing to bet my primary on someone else's success. Kinda like motor oil; when someone recommends "Brand A" oil to somebody because they've "Been using it for 20k miles with no problems", that means nothing to me. I assume by "no problems" they mean the engine hasn't seized or blown up; heck I know of quite a few cars that have over 100k miles on them using no-name dime store oil bought on clearance and have not had any such "problems."
But that doesn't mean I'm gonna run it in my equipment...
yeah!!!
it's not like ATF was designed for a transmission!
like say a C6 behind a 460cu or a th400 behind a 454.
it's not like ATF was designed for a transmission!
like say a C6 behind a 460cu or a th400 behind a 454.
Originally Posted By: FowVay
Many years ago when I raced 125cc and 250cc two-stroke motocross bikes, I'd use ATF in their gear boxes. I never experienced a lubrication failure.
I did too in my 2-smokes. Shift quality was improved over motor oil. Never a failure either.
Many years ago when I raced 125cc and 250cc two-stroke motocross bikes, I'd use ATF in their gear boxes. I never experienced a lubrication failure.
I did too in my 2-smokes. Shift quality was improved over motor oil. Never a failure either.
After having the Castrol ATF+4 in the primary for almost a week now I am amazed at how smooth shifting is as a result of presumably reducing drag on the clutch. I know there is some skepticism but I really don't consider this an experiment or overly risky as a large and well respected manufacturer of clutches for Harley, Barnett, even recommends it. In considering ATF's I reviewed some posts here on BITOG and settled on ATF+3 as it has some friction modifiers in it. When I got to the store all they has was the newer Castrol ATF+4, a synthetic product according to the label. I will keep an eye out for shavings and keep an eye on the tensioner shoe and will report back to everyone in the future.
You didnt break any gears, but there are those who have analyst tested atf in a 2stroke tranny, found very elevated metal counts over a typical heavier viscosity.
Ford tends to use atf in its manual trannies some times, But I much prefer a a real manual heavier gear lube.
Ford tends to use atf in its manual trannies some times, But I much prefer a a real manual heavier gear lube.
Originally Posted By: rn2fine
After having the Castrol ATF+4 in the primary for almost a week now I am amazed at how smooth shifting is as a result of presumably reducing drag on the clutch. I know there is some skepticism but I really don't consider this an experiment or overly risky as a large and well respected manufacturer of clutches for Harley, Barnett, even recommends it. In considering ATF's I reviewed some posts here on BITOG and settled on ATF+3 as it has some friction modifiers in it. When I got to the store all they has was the newer Castrol ATF+4, a synthetic product according to the label. I will keep an eye out for shavings and keep an eye on the tensioner shoe and will report back to everyone in the future.
I put B&M Trick Shift in my primary at about 600 miles and never looked back.
After having the Castrol ATF+4 in the primary for almost a week now I am amazed at how smooth shifting is as a result of presumably reducing drag on the clutch. I know there is some skepticism but I really don't consider this an experiment or overly risky as a large and well respected manufacturer of clutches for Harley, Barnett, even recommends it. In considering ATF's I reviewed some posts here on BITOG and settled on ATF+3 as it has some friction modifiers in it. When I got to the store all they has was the newer Castrol ATF+4, a synthetic product according to the label. I will keep an eye out for shavings and keep an eye on the tensioner shoe and will report back to everyone in the future.
I put B&M Trick Shift in my primary at about 600 miles and never looked back.
Necro bump.
It's presumably been 4+ years of ATF in the primary. What's the verdict?
It's presumably been 4+ years of ATF in the primary. What's the verdict?
I'm going 50k miles with Amsoil Type F in my primary. Still shifts better than OEM fluid, and no issues on my 03 RK.
I used Redline D4 atf in my Dad's softail and it made a noticeable improvement in shifting and finding neutral.
rn2fine any updates? I switched to atf beginning of this season with 5k miles on a change so far. Changed engine oil and atf this last weekend. There was no metal dust on a drain plug of the primary.
Sense it's been some time time hows your bike doing?
Sense it's been some time time hows your bike doing?
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