Paralever U-Joints: Correct Phase?

[Wallowa]

Paul Graves wrote a great article in the "BMW ON" May 2009 on "Driveshaft Operation and Maintenance". In that article he went into detail of why it is critical to get the U-Joints on driveshaft "in the correct phase" to prevent damage to the joints and shaft. Especially on the GS due to the long suspension travel.

I have read the article several times but can't visualize either the correct orientation or how having the u-joints in the wrong positions will lead to stress and damage.

Can someone please post a photo showing all the U-Joints aligned correctly ['correct phase'] ?

Thanks...

 

[marchyman]

Can someone please post a photo showing all the U-Joints aligned correctly ['correct phase'] ?

Scroll down a bit for a diagram of two u-joints in phase.

http://www.custompistols.com/cars/articles/ts_ujoints.htm

 

[Wallowa]

MM...Thanks Again...

Scroll down a bit for a diagram of two u-joints in phase.

http://www.custompistols.com/cars/articles/ts_ujoints.htm

Thanks for the visual MM! Also on Adv forum it was stated that all paralever shaft u-joints in Hexheads and in fact all since '04 [?] CAN'T be out of phase, since shaft and u-joints are one piece..

Paul Graves: Any clarification? My comprehension seems weak... Thanks...

 

[henzilla]

Yes, the EVO drives have one piece shafts now. Don't have the phasing issue at all on the Hexheads

kinda small graphic...

 

[Wallowa]

Why Two Clips?

Yes, the EVO drives have one piece shafts now. Don't have the phasing issue at all on the Hexheads

kinda small graphic...

I posted same image on another forum...but I don't remember two clips on mine?

Only clip I believe is at trans end...

 

[PGlaves]

Look at the graphic Henzilla posted. It does show the correct orientation for two U joints.

 

[henzilla]

I posted same image on another forum...but I don't remember two clips on mine?

Only clip I believe is at trans end...

I know for sure there is one at tranny end cause you feel it snap in place when installing the shaft. The way the drive hangs up as you hinge it makes me think maybe there is one there also...am pulling one in a few days and will take a peek.

That graphic is from OEM parts fiche.

 

[Wallowa]

Yup..Paul, Do You Agree?

Look at the graphic Henzilla posted. It does show the correct orientation for two U joints.

Yup from Max BMW fiche...but Paul do you agree that Hexhead u-joint are always in correct phase and that they can never be in an incorrect phase relationship?


Hey Big Hen...that was what I was trying to say..only clip on splines that I am aware of is on the trans end and not on FD end...but fiche shows two clips.

 

[PGlaves]

Yup from Max BMW fiche...but Paul do you agree that Hexhead u-joint are always in correct phase and that they can never be in an incorrect phase relationship?


Hey Big Hen...that was what I was trying to say..only clip on splines that I am aware of is on the trans end and not on FD end...but fiche shows two clips.

I haven't tried to separate the two halves of a Hexhead shaft so can't say for sure - but folks I trust tell me they are bonded as a single piece. At least one year GS had one wider spline/groove so would only go together one way. Not sure which year(s) that was.

If it comes apart put it back together in phase. If not - be sure it looks right or ask questions.

 

[henzilla]

Look at the graphic Henzilla posted. It does show the correct orientation for two U joints.

Hey Paul, my dad used to say "mirror the middle"...after I ruined yet another Blazer set of U-Joints...I guess it makes sense to me now looking at it 30 years later

 

[henzilla]

This is a R850R driveshaft from todays work...I know it's not a HEXhead...just trying to clarify the description.

this photo is in phase...notice the middle "mirrors each other in yoke orientation:

another "in phase" attached to FD...middle yokes still mirror each other:

this photo is 90 degrees out of phase:

This is one variation of "in between" which is possible with 16 or so spline teeth: