Driveshaft installation into new carrier bearing

[brider]

This relates to a Tonti (my Cal 2) swingarm and driveshaft u-joint: I installed a new carrier bearing into the swingarm, and now that I am attempting to install the 1-piece driveshaft, I find that the u-joint is a VERY slight interference fit into the carrier inner race, so that due to the deep "well" of the housing on the swingarm that houses the u-joint, I can't see if the u-joint has been inserted all the way into the bearing.

I have an extra (new) carrier bearing, and tried to fit it on the driveshaft on the bench, and it would not slip down into seated position at ALL by hand.

So with the swingarm on the bench resting vertically on the rear-drive flange and the driveshaft inserted, I tried to align the u-joint as much as possible to axial-center, and tapped it with a soft mallet. It inserted to some degree, but I can't see down in there to see how FAR.

What is the proper procedure?

[guzzisteve]

The way you are doing it, it'll work.  You could freeze the shaft, then warm up inside of bearing too.

[chuck peterson]

No banging w mallets hammers. Carry the two to a machine shop and ask for a interference fit. If all else fails a guzzi shop should have the tool.

[brider]

It occurred to me that freezing the shaft was what I SHOULD have done (thanks for the reminder, Steve), and I could also measure the length of the bearing area on the shaft, insert the shaft so that it just starts insertion, then mark off the measured length on the u-joint yoke so I know when it's fully inserted.

I've read a lot here about carrier-bearing replacement, and driveshaft variations/rebuilds/repairs, etc, but I don't recall reading ANYTHING about this tight fit into the bearing. Usually it's just "I replaced the carrier bearing, re-installed the driveshaft and put the swingarm back on...", nothing about " I replaced the carrier bearing, took the driveshaft to a machine shop to turn down the shaft to get a slip fit into the carrier...".

BTW, it's already an interference fit, I believe the best would be a .0000/.0003 clearance, something like that.

[jwinwi]

MG Cycle sells the proper tool:
http://www.mgcycle.com/index.php?main_page=product_info&cPath=317&products_id=4677

[Rolf Halvorsen]

One side of the UNI is Ø30,2mm while the other is only Ø30,0. (It is impossible to see this differanse with your eyes.)
Be sure to put the right side into the bearing.

[guzzisteve]

You got the deal figured out. Put on the swingarm, you'll know if it's in. You can leave the heavy rear drive off. You can look up the shaft housing side w/light and see if it's flush or a bit more in there. I hang the swingarm w/tie down strap, takes the weight off of doing the labor.

[brider]

MG Cycle sells the proper tool:
http://www.mgcycle.com/index.php?main_page=product_info&cPath=317&products_id=4677

That tool says it won't work for the automatics. Wonder why? Different yoke geometry?

I am becoming concerned now about how to install it if freezing the driveshaft doesn't work. MG Cycle emphasized Chuck's admonishment about pounding on it with my soft mallet.

Sheesh, I never would have thought this would be a stumbling block, how in the heck do you hold that floppy thing in place to press it in? Calling all automatic owners?!!!

[chuck peterson]

the one piece auto driveshaft can only go in one way...you need that interference tight fit to make sure it’s spinning the bearing and not spinning inside the bearing... the bearing can be pulled in from the rear w a threaded rod/nut and plate, but interference fit I understand to be done by a hydraulic press exerting tons of pressure in a measured adjustable way, probably without turning down the shaft...Still, there seems to be no comment about it in an SP workshop manual I have at hand..

Check out the comments by the mg boys under the installation tool...banging and hammers aren’t friendly to needle bearings

What you have is a test for a machinist.....te he

[1down5up]

In the past I have used some pvc piping that's just a tiny bit bigger than the universal joint to hold it all straight and vertical, then a few taps on the drive shaft inserted into the uj to knock it into the bearing, Chuck the uj in the freezer first.

[Peter949]

After installing a new carrier bearing in my 84 California II swingarm, I used a hydraulic  press to push the U-joint into place.



This tool certainly would have been useful to hold things straight!

[brider]

Sure would've been great if MG had put a scale or maybe a U-joint next to the tool for a little context....I assume the larger diameter slips OVER the yokes?

Still don't understand why it wouldn't work for automatic u-joints unless the dia of the yokes is different. But why would Guzzi go to the expense of spec'ing a different-dia yoke for a 1-piece driveshaft?
OR, maybe the tool depth is calibrated so it bottoms out in the housing at the correct insertion depth.....but then again, why would a 5-sp u-joint have different height geometry than the automatic?

[Antietam Classic Cycle]

Sure would've been great if MG had put a scale or maybe a U-joint next to the tool for a little context....I assume the larger diameter slips OVER the yokes?

Still don't understand why it wouldn't work for automatic u-joints unless the dia of the yokes is different. But why would Guzzi go to the expense of spec'ing a different-dia yoke for a 1-piece driveshaft?
OR, maybe the tool depth is calibrated so it bottoms out in the housing at the correct insertion depth.....but then again, why would a 5-sp u-joint have different height geometry than the automatic?

The "yokes" are smaller - the same size as the Loopframe part IIRC.

[geodoc]

I made my tool out of a piece of PVC tubing that slides into the drive shaft and is just a close enough fit to keep the u-joint from wobbling then stick it in a floor press and press 'er home. This after cleaning the mating surfaces with acetone and applying very thin smear of red Locktite.

"The inventor, denied his patent rights, glumly returned to his tree".





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