Loose shift lever repair

[hein]

Good afternoon Mark.

   I still agree with you about the teflon coated bushing solution as being a good idea but your numbers confuse me. You stated a.5mm. clearance which converted into inches is approx. .020 Considering that a beer can is .004 and a curly red hair is approx. .002 you would need about 4 beercans or 10 rch to achieve a zero clearance fit. . At a .020 fit, based on a lever approx 4" long with a bushing approx .750 wide and using the half clearance measurement as reference point,.010, you would end up with .283 deviation in either direction at the shifter peg for a total of.566 inches of "slop". This is what we are trying to get rid of.

   Ignore my calculations and use Dads FJ's measurements to understand my confusion.
1) id. of bushing 12.02 mm.
2) od. of shaft    11.95 mm.
3) clearance          .07 mm. or .0027 thou.
4) allowing for an interferance fit

into the lever  of .001 or slightly less the running clearance would be about .002 or 10% of what you call for.

Either you speced out the wrong bushing , used a larger shaft measurement Or just maybe moved a decimal point in the wrong direction.
.5mm.=.0196 in.
.05mm.=.00196 in. pretty close to Dads FJ's measurement.

I would defend the oilite bushing solution as still being practical. Pat's suggestion of adding a grease fitting is still a very commen one in industry and still used on motorcycles. Since your neck bearings are also lubed by grease, and I doubt that you would repack them on the same frequency as the drive chain gets lubed, I think that solution is low maintenance. I do agree that teflon is lower maintenance but in a sloppy fit enviroment the teflon would be gone rapidly.

Now its time to empty more cans and check on the wall thickness consistency.

Nothing like a good debateto bring on thirst.      Hein.

[FJmonkey]

Good afternoon Mark.

   I still agree with you about the teflon coated bushing solution as being a good idea but your numbers confuse me. You stated a.5mm. clearance which converted into inches is approx. .020 Considering that a beer can is .004 and a curly red hair is approx. .002 you would need about 4 beercans or 10 rch to achieve a zero clearance fit. . At a .020 fit, based on a lever approx 4" long with a bushing approx .750 wide and using the half clearance measurement as reference point,.010, you would end up with .283 deviation in either direction at the shifter peg for a total of.566 inches of "slop". This is what we are trying to get rid of.

   Ignore my calculations and use Dads FJ's measurements to understand my confusion.
1) id. of bushing 12.02 mm.
2) od. of shaft    11.95 mm.
3) clearance          .07 mm. or .0027 thou.
4) allowing for an interferance fit

into the lever  of .001 or slightly less the running clearance would be about .002 or 10% of what you call for.

Either you speced out the wrong bushing , used a larger shaft measurement Or just maybe moved a decimal point in the wrong direction.
.5mm.=.0196 in.
.05mm.=.00196 in. pretty close to Dads FJ's measurement.

I would defend the oilite bushing solution as still being practical. Pat's suggestion of adding a grease fitting is still a very commen one in industry and still used on motorcycles. Since your neck bearings are also lubed by grease, and I doubt that you would repack them on the same frequency as the drive chain gets lubed, I think that solution is low maintenance. I do agree that teflon is lower maintenance but in a sloppy fit enviroment the teflon would be gone rapidly.

Now its time to empty more cans and check on the wall thickness consistency.

Nothing like a good debateto bring on thirst.      Hein.

I have already jumped off this train. In either case I think we already agree that a properly sized fit between bushing and shaft is best in all cases. Sintered bronze/Oilite with zerc fitting vs. Steel PTFE. both should last another 25 years, one with some additional maintenance to keep lubed. A sloppy fit on either will reduce life by the amount of sloppy fit. My Angelest crest/Bouquet Canyon ride is over for today, 180 odd miles of twisties in this nice cool Kalifornia weather, the chain is lubed, Battery Tender on, cover in place, time for a beer .

[skymasteres]

You know,

It's funny that I will have just completed the same ride Mark mentioned in the last post as we had a conversation about this very topic...

Since I already do a modification for the Honda guys that replaces the original shifter bushing with a set of ball bearings I figured I would revisit this issue. http://www.v4market.com/Trans-Complete-Shifter-Service_p_178.html

Especailly with the amount of slop I have in the linkage on my bike. The only disadvantage of the modd that I do for the Magnas is that if you go down and whack the shifter hard enough to bend it, you trash the bearings. (Only had it happen once so far. But then again, you usually shear the stock bolt anyway so I guess it's a wash) The point is, I have had several Magna owners tell me that they were having a second gear issue and that after putting the upgraded shifter on the issue went away. Just taking out all the slop in the linkage. There are two places that you get this extra slop. The bushing that the arm rides on, and the worn ball joints.  For the ball joints I have some metric ones that were made up for me with nylon lineres and seals. They will last a long time and they'll fit the FJ.

The point is, the bearing that I'm pressing in for the Magnas have a 14mm OD, so I have the tooling to bore the correctly sized hole. I'll give one of these PTFE lined bushings a shot and see if that'll be as tight as doign the bearing thing. If not I'll just put in a set of 12x18mm bearings.

[fj11.5]

Sounds good mate,count me in

[skymasteres]

Well, I have to say that I am very disappointed with the precision of the fit with the McMaster Carr part
number 6679K17 Teflon lined bushing. It is just as loose in my opinion as the original assembly.
(I just put the new bushing over the an original shifter stud to check the fit before continuing)

Definitely not worth doing any machining to make it fit. So, bushings are out, full speed ahead on ball
bearings. Well, that and just generally eliminating play from the assembly. Step one was replacing the
worn out ball joins with my improved ones. This was a little more challenging than I expected as the
original studs are swaged in place and special care needs to be taken to avoid damaging the aluminum
components when pressing them out.

Here is the shifter installed with the upgraded ball joints.



And wow. Just from doing that, it makes a big difference in the amount of foot travel and crispness of the shift. 

As for the bearings are concerned I have devised a method on paper to replace the original shifter bolt
with an 8mm bolt, some washers, a spacer, and a couple bearings. The best part is, if it works out the
way I hope, it'll be a upgrade and replacement for the original shifter pivot bolt. And it won't require and
machine work to be done to the shifter.  I'm just EARGERLY waiting for the bearings I ordered from a
company in Canada to arrive to make sure.    (On a side note, I just can't seem to get stuff
made in the USA anymore. I had to go to Canada for the bearings, England for the washers, and India for the bushing...)

[aviationfred]

I am sure a new shifter bolt would also help. Just like the inner bushing of the shift lever is worn after 20+ years, the O.D. of the shifter bolt would likely have worn.

New shifter bolt from RPM.

http://www.rpmracingca.com/proddetail.asp?prod=ShifterPivotBolt

Fred

[FJ_Hooligan]

Would it have been possible to just drill the old ball joint shafts out of the shifter lever and linkage?

[Dads_FJ]

I am sure a new shifter bolt would also help. Just like the inner bushing of the shift lever is worn after 20+ years, the O.D. of the shifter bolt would likely have worn.

New shifter bolt from RPM.

http://www.rpmracingca.com/proddetail.asp?prod=ShifterPivotBolt

Fred

Good point, my shifter bolt was only 6 years old when I performed this mod.

[skymasteres]

Yes it is. Basically what I did was cut off the ball, center punched the swaged stud, drilled it out,
then used a punch with a socket over the part where the ball was cut. I didn't completely drill it out
because the hole wasn't completely on center and I didn't want to damage the shifter.

Here was the shifter that came with the bike.



You can see that the PO sheared the shifter bolt when he went down and replaced it with an 8mm bolt,
12x25mm bushing, and a nut to hold it in place. I liked where he was going with replacing the "unobtainium"
shifter pivot bolt.

The bolt that Randy came up with is awesome, but my method should be able to completely replace it with
a ball precision bearing supported pivot for less than the price of the RPM part.


 
I'm still waiting for my bearings and washer though.

[FJ_Hooligan]

Excellent idea!  Very interested as my shifter linkage is kind of sloppy also

[skymasteres]

I'm telling you, I'm just on pins and needles waiting for my bearings to come in. I really want to see
how this goes together. (I'm already loving just having the old ball joints replaced) 

In the mean time, so that maybe you can understand why I am so excited about this, here is some
feedback I got over at the V4 Honda forum about the shift modd for those bikes.

[racerrad8]

(On a side note, I just can't seem to get stuff made in the USA anymore. I had to go to Canada for the bearings, England for the washers, and India for the bushing...)

Mike,

I am not sure why you had to go to Canada for the bearings, those bearings are very popular in the RC car world. I found what looks like the bearing you are looking for, MF128-ZZ readily available in the US as well as highly sold on eBay but mostly by international vendors.

Here is the first US vendor I found; http://www.bocabearings.com/bearing-inventory/Radial-Bearings/33/8x12x3-5-MR128ZZ

But with pricing as cheap as this it is probably worth waiting on them for 7-10 business day; http://www.ebay.com/itm/10pcs-8-x-12-x-3-5mm-MF128zz-Shielded-Flanged-Model-Ball-Flange-Bearing-8-12-3-5-/180915644963?_trksid=p2054897.l4275

Since the shift pivot bolt is a dual purpose item as it must retain the foot peg rigidly to the frame and the shifter must pivot, are you going to rely solely on the internal spacer of the bearing to hold the bolt tight and keep the foot peg tight? The surface area of the center bearing race as well as the surface area of the spacer might not be enough to keep the foot peg tight.

Also, the foot peg is rubber mounted which allows it to twist and the flange of the O.E. bolt and rubber backed washer limit the travel. That might cause some issues of rubbing the shift lever if you are just using a washer between it and the foot peg.

Also, how are you going to allow for the rubber backed washer on the late model FJ as the washer is recessed.

And finally, see you have both shift levers in your pictures, I just want to make sure you know there are both steel and aluminum shift levers depending on the year of the bike.

I am not sure if you are going to be able to do the mod cheaper than the, as you stated "unobtainium", stainless steel shift bolts I had manufactured. By looking at the price of just the two ball joints you installed, you are just a few bucks cheaper and you still have not addressed the shifter pivot parts and the labor you are going to put into completing the modification.

I hope you get it all sorted, just remember you have different model years and slight differences in the shifter pivot bolt and foot peg mounting.

Randy - RPM

[skymasteres]

It's all sorted Randy. Check your mail.

The bearings are Stainless outers with a chromoly inner race to handle the load.

It'll hold and I didn't have to resort to cheap chinese crap.

[skymasteres]

Well shoot, it wouldn't let me modify my post.

I said I can't get stuff "made" in the USA anymore. As in made to my specs.

And you're exactly right. The biggest design issue is just making sure that that shim, bearing race, spacer, and washer stack can bear the required loads reliably without exploding. If you used cheap off the shelf bearings I really doubt that they would hold up.

It is critical that those inner races and the spacer hold because,  at 24ft# of torque, that 8mm bolt is generating a compression force of about 4500#. With the hardware in the middle that's about 64,951.72 PSI that needs to be withstood. Mild steel yields at 36000PSI and has an ultimate strength of about 58000PSI. If you torque the bolt to 20ft# you can get away with mild steel. But if you want the full torque you need to use grade 5 or class 8.8 hardware respectively. Especially when you consider the bending loads on the bolt.

The bolt is a simple, commonly available class 12.9 socket head bolt. Just for extra security seeing as it's yield strength is around 159,500 PSI. About $1.75 at the local hardware store. Fortunately some of the bending loads will be mitigated by the arrangement of the washers on the footpeg side. (if the rubber backed washer is retained it's recess will be filled with 8mm id shims.)

The only real critical part fitment wise is the center shim between the bearings. Too big, and it won't grab the shifter bore properly. Too short and it'll put too much side load on the bearings. This is what I have to play around with verify the concept.

I guess the proof will be in the pudding though. When I get my bearings in and bolt it all together I'll be able to see if it works.  
(I can't wait)

[The General]

I said I can't get stuff "made" in the USA anymore. As in made to my specs.

And you're exactly right. The biggest design issue is just making sure that that shim, bearing race, spacer, and washer stack can bear the required loads reliably without exploding. If you used cheap off the shelf bearings I really doubt that they would hold up.

It is critical that those inner races and the spacer hold because,  at 24ft# of torque, that 8mm bolt is generating a compression force of about 4500#. With the hardware in the middle that's about 64,951.72 PSI that needs to be withstood. Mild steel yields at 36000PSI and has an ultimate strength of about 58000PSI. If you torque the bolt to 20ft# you can get away with mild steel. But if you want the full torque you need to use grade 5 or class 8.8 hardware respectively. Especially when you consider the bending loads on the bolt.

The bolt is a simple, commonly available class 12.9 socket head bolt. Just for extra security seeing as it's yield strength is around 159,500 PSI. About $1.75 at the local hardware store. Fortunately some of the bending loads will be mitigated by the arrangement of the washers on the footpeg side. (if the rubber backed washer is retained it's recess will be filled with 8mm id shims.)

The only real critical part fitment wise is the center shim between the bearings. Too big, and it won't grab the shifter bore properly. Too short and it'll put too much side load on the bearings. This is what I have to play around with verify the concept.

I guess the proof will be in the pudding though. 
(I can't wait)

Arnie understands and in fact taught us a lot about the talk rating of the gear lever assembly at the 2012 Aussie Rally. In fact he was an award recipient as a result of his efforts. He may chime in, but I have an idea he would dispute the yield strength requirement...