Engine balancing

[quixotic]

The jam nuts should really have all their threads engaged.  Then they can be snugged down nicely.

If you can't get jam nuts all the way onto the stud, I wouldn't trust threadlocker. I'd probably go for nylock main nuts or drill the stud to accept castle nuts and cotter pins... but that could mess around with getting the torque "just so."

Btw, I wouldn't consider split lock washers for fear that they'd crack.

I just had a closer look at it, and there are existing lock washers on both sides.  So if I take those off, I think there will be ample thread for the two torquing nuts, as well as the two locking nuts (and some locktite just for added insurance).

[Luca]

I think they're wave washers, though, not split lock washers.  You should have a washer between the first nut and the frame.

IMO a nylock nut and wave washer would probably be a good way to start, with some frequent checks and tools under the seat.

I seem to recall hearing that the old vibration damping kits came with longer engine mount studs.

[quixotic]

Wow!  It worked!  I gotta admit that I was a bit skeptical at first.  But now the 4,000 to 5,000 rpm range is a smooth as butter.  There's a minor little buzz around 4,000, but it's in a very narrow rpm range and I can easily live with it.  

I used the sway bar bushings from Princess Auto (mentioned above).  I just reamed out their holes a bit and cut them in half, so that each half was about 7mm's thick.  I then inserted them in some 1/4 inch chunks of teflon, so that they wouldn't get compressed out of shape.  

I couldn't find the cupped washers anywhere, so if anyone has a link, that'd be great.  I'm not terribly confident about the long-term viability of the teflon, so I think I'll shortly re-do the housings with chunks of aluminum.

[bjamesw]

If the auto parts counter guy is willing, look through a few boxes of random sway/torsion bar end links since many of them are equipped with cup washers.  They're surprisingly inexpensive.  I think I got sets from O'reilly auto for a 2005 Chevy Astro.   I got these last year to mount 10hp Briggs engine to a log splitter.  An old engine that was vibrating badly enough to crack welds and these worked a charm.

I'm encouraged by your feedback.   I may just have to try this.  With the torque and radial loads imposed on these bearing a Boxer I might be more inclined to go for the more rigid and dense red urethane versions. These parts were designed, at the mounted ends of sway bars, to bear axial load primarily (if I correctly recall the distinction between those two).    

[quixotic]

If the auto parts counter guy is willing, look through a few boxes of random sway/torsion bar end links since many of them are equipped with cup washers.
 

There were cup washers included with the sway bar end link kit I have, but they are each about 2mm thick (at least).  So there wouldn't be any room left for rubber.

 With the torque and radial loads imposed on these bearing a Boxer I might be more inclined to go for the more rigid and dense red urethane versions. These parts were designed, at the mounted ends of sway bars, to bear axial load primarily (if I correctly recall the distinction between those two).    

I might try that also, since even with 12 foot/lbs of torque, a small amount of the black rubber had a tendency to sqeeze out from its enclosure.

[quixotic]

Here are the aluminum/polyurethane washers I made.  Both materials were quite easy to work with.  The aluminum (2 x 1/8" bands) is easy to cut even with a ten dollar coping saw.  The polyurethane is easy to cut with box cutters and/or the coping saw.  The poly is almost 8mm's thick, so I did some minor shaving where the unit needs to slide between the frame and the engine (a dab of grease helped also), and also where the big bolt needs to be drifted through.  I also had to cut off another couple of mm's of aluminum for the right side, where it would have otherwise interfered with the oil filter cover.  

For the vibration alleviation, it seems to work almost as well as the teflon.  Not perfect, since I suspect that the aluminum transmits a bit of vibration.  But nonetheless a vast improvement for mere pennies.  Now I can cruise at the speed limit (110 kph), instead of having to choose between 100 or 125.

Glad I changed the teflon out.  The data sheets for it show that tensile strength is reduced more than 90% at 150 degrees fahrenheit.

[R65Singh]

Here are the possible best fit cup washers that would be perfect for this job. Very thin and almost correct size. Take a look at this listing.  You just need those washers and nothing else. Would be nice to find those at a BMW dealer or Motobins?

http://www.ebay.com/itm/BMW-Airhead-R60-R75-R90-6-Medium-Height-Speedometer-Bracket-and-Hardware-/221490003701?pt=Motorcycles_Parts_Accessories&hash=item3391d53ef5&vxp=mtr

[quixotic]

Here's the latest iteration.  A sandwich with a 1.5mm thick washer on both sides and a chunk of polyurethane 3mm's thick in the middle.  And then a 6mm slice of aluminum tubing (17/16th's inch ID approx) to keep the poly from squeezing out.  The tubing extends far enough out to minimize engine to frame contact, and the washers were ground down so that they were just a tad smaller than the ID of the tubing.  So the theory is that the engine pushes on one washer and the frame pushes on the other, and the poly in between absorbs any vibration.  

It seems to work fairly well.  At least as well as the set-up that I initially tried with the teflon.  Whereas with the stock washers, the vibration band was about 1,000 rpm wide, the vibration band is now less than 200 rpm wide.  

The biggest hassle turned out to be grinding down the washers with an angle grinder.  It would've been nice to find something off the shelf which fit nicely inside the tubing.  However, even just finding a large washer that's sturdy and also only 1.5mm's thick might be the difficult part.  

Now I'm curious about teflon, and whether a simple 6mm wide washer made out of it might work.  I don't know if it would absorb vibration, and I don't know if it would survive the heat.  Does anyone happen to know how hot the exterior surface of the sump gets up to?

[quixotic]

Here are the possible best fit cup washers that would be perfect for this job. Very thin and almost correct size. Take a look at this listing.  You just need those washers and nothing else. Would be nice to find those at a BMW dealer or Motobins?

http://www.ebay.com/itm/BMW-Airhead-R60-R75-R90-6-Medium-Height-Speedometer-Bracket-and-Hardware-/221490003701?pt=Motorcycles_Parts_Accessories&hash=item3391d53ef5&vxp=mtr

Do you know if there are four cup washers included there?  I'm mighty tempted to order that unit.

[Bob_Roller]

quixotic, the last picture of what you have made, is just about a duplicate of the Luftmeister vibration isolators .

About the only difference, is that the Luftmeister parts were all bonded together .

[Barry]

Now I'm curious about teflon, and whether a simple 6mm wide washer made out of it might work.I don't know if it would absorb vibration, and I don't know if it would survive the heat.

Teflon would have no problem at all with the heat.

[mrbuck]

For what it's worth here is another opinion.

http://www.nebcom.com/noemi/moto/r65faq.html#ENGINE_VIBRATION

[mrbuck]

I didn't realize this link on "engine vibration"  would transfer all of the blog.  But it's all good stuff.  So, enjoy.

[quixotic]

Now I'm curious about teflon, and whether a simple 6mm wide washer made out of it might work.I don't know if it would absorb vibration, and I don't know if it would survive the heat.

Teflon would have no problem at all with the heat.

I've mistakenly been using teflon and what I've got (UHMW plastic) interchangeably.  But they're quite different...especially with regard to heat.  
http://www.articletrader.com/computers/software/uhmw-sheets-versus-teflon-ptfe-sheets.html

Maybe I'll try to track down some of the former:
http://www.walmart.com/ip/Teflon-Pressing-Sheet-18-x-18/17337950

But something tells me that it would likely still transmit vibration (or else Luftmeister would've already tried it).

[quixotic]

quixotic, the last picture of what you have made, is just about a duplicate of the Luftmeister vibration isolators .

About the only difference, is that the Luftmeister parts were all bonded together .

Does you know if the Luftmeisters were designed to be used on all four engine mounts?  Or just the front two?