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still confused about primary fluid?

09 deluxe

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I know everyone uses 20W50 for the engine. I'm going with a syn. Probably Spectro or M1
Seems to be some debate about the weight for the tranny, but Spectro full syn 6 speed 75w140 sounds best. (but the weight seems higher than recomended?or is it?)

Still a little out to lunch on primary. I was thinking Spectro heavy duty primary ( I think its 85w). Is a multiple weight oil better? Isn't HD F+ a multiple weight? Is the straight weight just better for hot places or summer riding, and go with multiple weight for spring to fall riding?

Thanks for you help
 
I know everyone uses 20W50 for the engine. I'm going with a syn. Probably Spectro or M1
Seems to be some debate about the weight for the tranny, but Spectro full syn 6 speed 75w140 sounds best. (but the weight seems higher than recomended?or is it?)

I hear ya on the weight confusion.
HD recommends what they sell.
75w140 in a tranny is not too thick.

I use Mobil 1 v-twin 20w50 full synthetic in the motor.
Royal Purple max gear 75w140 synthetic or Spectro 6 speed 75w140 synthetic in tranny.
And HD Formula+ in primary.

Stay away from the synthetics in the primary. The coefficient of friction in synthetics are too slippery for proper clutch operation.
 
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I modified your quote for YOUR ANSWERS BELOW:

use 20W50 for the engine. FULLY SYNTHETIC
Spectro full syn 6 speed 75w140.
Spectro heavy duty primary.
Thanks for you help

I go differently but the above is GREAT STUFF to use

***** I LIKE MY STUFF BETTER THO'

FULLY SYNTHETICS I USE

*****I use 20/50 redline year around in my engines / only harley filters

BUT even harley says you CAN use a STRAIGHT WEIGHT OIL in too COLD or too HOT climates...
but most will use the 20/50, takes in the climate and daily changes and will work good for MOST ALL harleys year around.

*****I use redline MTL in chain/clutch case (primary case)

MTL is a redline product:
manual trany/transaxle lube, SAE 70W80 API GL-4 GEAR OIL...... they do have a new product out LABELED for v-twins primary use. (good stuff)

I put over 117,000 miles on a 2000 dyna HOT-ROD (100+ hp) using ONLY MTL.... The clutch was original with no problems,,, ALL THOSE MILES! Still doing good when bike sold.

*****I use redline HEAVY SHOCKPROOF GEAR OIL in transmissions

this redline product allows LESS metal to metal contact (gears) and greatly reduces wear... giving a cushion effect between the gears....

####75/250 rated GEAR OIL....... 250% reduced wear than common used GEAR OILS in compared studies.

REDUCES GEAR NOISE: this is a BIG-E in the HD 6 speeds... NOISY BUGGERS TODAY...


I hope you get something out of MY suggested LUBES, also the ones YOU mentioned will work better then the HD recommended ones..
SYN3 is a SIN!

I buy my redline products on-line and several sell it at a good price...
BUT compare the $$$ on any on-line site you buy from...

signed....BUBBIE
 
The purpose of lubricant in the primary is actually for cooling, not lubricating.
( ya think your clutch wants "lubed", no it wants cooled).
At a couple bucks a quart, Auto trans fluid (Dex/Merc) will work fine, but stay away from anything synthetic. When in doubt, run HD primary fluid and be done with the debate.
 
IMO, HD Formula+ is OK for the primary, but if you want to spend a few more $$$ - go w/Spectro. I put Formula+ in whil winterizing the bike & will use Spectro this coming fall when I winterize again.
 
The purpose of lubricant in the primary is actually for cooling, not lubricating.
( ya think your clutch wants "lubed", no it wants cooled).
At a couple bucks a quart, Auto trans fluid (Dex/Merc) will work fine, but stay away from anything synthetic. When in doubt, run HD primary fluid and be done with the debate.

LOL....... BUT you better RE-THINK this statement above in red.
THE CHAIN and the adjuster also... COOL!

signed....BUBBIE
 
The purpose of lubricant in the primary is actually for cooling, not lubricating.
( ya think your clutch wants "lubed", no it wants cooled).
At a couple bucks a quart, Auto trans fluid (Dex/Merc) will work fine, but stay away from anything synthetic. When in doubt, run HD primary fluid and be done with the debate.


Disagree here. The chain as well as the sprockets need lubrication which the ATF just doesn't do well in the HD primary. There's also other things to consider when using the ATF in the primary like the stator, wiring and connections, it's not just about the clutch and just cooling. Trans oil shouldn't be used in an engine or fork oil in the trans because it wasn't MADE for it.
 
I know everyone uses 20W50 for the engine. I'm going with a syn. Probably Spectro or M1
Seems to be some debate about the weight for the tranny, but Spectro full syn 6 speed 75w140 sounds best. (but the weight seems higher than recomended?or is it?)

Still a little out to lunch on primary. I was thinking Spectro heavy duty primary ( I think its 85w). Is a multiple weight oil better? Isn't HD F+ a multiple weight? Is the straight weight just better for hot places or summer riding, and go with multiple weight for spring to fall riding?

Thanks for you help

Any of your options above will do an excellent job. I personally use:

M1 VTwin 20W-50
Spectro Heavy Duty Platinum 6-speed Transmission Oil
Spectro Heavy Duty Primary Chaincase Oil

HD Formula + in the primary is also an excellent choice.

TQ
 
I don't get why most on this site use 75W140. I've run 75W90 for 20 years with no trouble but we don't get a lot of days over 85 degree's. I can see it if you live in the south where you get lot of HOT day's but in the north I just think 75W140 is too thick for 40 degree weather. JMHO
 
if add all my Sportsters Miles up have well over 100,000 Trouble free Miles on them using strictly Amsoil 20W50 .. Far as the Tranny on the Ultra, Spectro Rules .. went in at 1,000 Miles

No internal engine or internal transmission work in 100K.? Those are very good numbers.
 
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