Final Drive Re-shim/Tightening Backlash—Easy

[mjlovstrom]

My 2004 FJR1300 with 88000 miles had a noticeable clunk coming the driveshaft and drive line when shifting and going on/off the thottle. At first I thought it was U-joints so I replaced those but was not the problem. Noticed excessive backlash at the Middle drive gear so re-shimmed that from .50 to .20 and made a big difference but still had clunk coming from final drive. Removed final drive and noticed excessive backlash in the gears// used a dial indicator to verify the measurement. Took final drive apart, and actually just needed to use a pry-bar/ big screwdriver to remove main gear and bearing. Measuring the shims I determined that it had previously been re-shimmed already from a .40 shim to a added/additional .30 shim for a total of .70. I replaced the .40 shim with a .50 and kept the .30 for a total of .80. Re-installed and again made a nice difference in the shifting quality and will tighten it up a bit more this winter to a total .90 in shims.

You can read my post about re-shimming the middle drive gear-- very easy// takes about 30 minutes and $10.00 in shims. It was obviously designed to be a maintenance item over time by the ease of the job.

Makes riding the bike much more enjoyable.

 

[RossKean]

Interesting.

I have never heard of that as an issue with FJRs - not even ones with high mileage. The amount of shimming you have done seems to be a lot. I have to wonder if there is something else going on there...

 

[Canadian Steve]

Just what kind of backlash numbers were you getting?

 

[mech 1 twa]

Parts do wear. Gears and bearings start to get additional clearance over time. Axle spines.

Interested how you know rear shims where already replaced? Factory marking?

Buy a new 4x4 truck Automatic. Nice and tight when new. 100k later a whole bunch of play in drive line. Transfer case, rear diff.

 

[mjlovstrom]

On the dial indicator I was at .028--- spec is .010-.018. Noticable even when turning the shaft by hand can get a noticeable sound when the gears make contact.. When I tightened it up quieted it down a lot. The tolerances are understandably tight when new so no noise/ clunk isn't heard, but after 90k gears will wear and tolerances will open up.

As far as thinking it was shimmed before, I can't believe Yamaha factory would use 2 shims and on the FIsch the stock shim shows .40 mm. Mabey from the factory they used 2 shims, but I doubt it. And I can't believe a new final drive from the factory would have to be shimmed up that far.

 

[mjlovstrom]

One other point, if you look at a feeler gauge making a .004 or a .008 change in a shim to get within spec really isn't making the earth move-- I can see a ring and pinon wearing that and more with lot's of miles... My Toyota Tacoma with 288000 has lots of backlash-- I here it every time I go from Forward into reverse-- CLUNK from rear end.

 

[TripperMike]

Makes sense to me. My '05 had developed a significant bit of sloppiness in the rear end. It never occurred to me that I could've so easily have been able to remedy that with shimming.

Thanks for posting this.

 

[mjlovstrom]

Yes it's not hard at all, and it took me about 2 hours total.. When you take the rear tire off, loosen the 6 ( I think there were 6) nuts holding the final drive plate-- just loosen them.. you will remove them fully when you remove the drive off the bike-- just makes it easier... Be sure to clean the drive good, as there will be caked on krud that could fall into the wrong places. I used a wire brush and followed up with a shop vac... You will have to pry off the plate with a screw driver/ prybar but takes little effort as it's just an o-ring sealing the unit. Take a look at the micro-fiche on-line to get a good idea how it's put together, and you will see that it's nothing but a Ring, Pinion, shims, a thrust washer an big bearing that you have to mess with... the bearing is pressed on the ring gear shaft and you don't have to worry about nothing on that. I literally took it out of the garage and was so happy that I didn't get a clunk everytime I shifted a gear or let off the gas and accelerated out of a corner--- very annoying.

One thing, when putting it back together the bearing/ ring gear is tough to get back in as it's a tight fit into the housing . I used a heavy rubber mallet and just tapped it around until it was fully seated... I didn't use, or need a press at all.

 

[mech 1 twa]

There is a short thread started by Constant Mesh about drive line slack-free play. He stated his rear wheel moved 2.5 inches or so measured at wheel or tire. I measured mine in first gear at rim its 1.75 .

Interesting. Search rear wheel its half way down page.

 

[redneckj]

One other point, if you look at a feeler gauge making a .004 or a .008 change in a shim to get within spec really isn't making the earth move-- I can see a ring and pinon wearing that and more with lot's of miles... My Toyota Tacoma with 288000 has lots of backlash-- I here it every time I go from Forward into reverse-- CLUNK from rear end.

My 01 4Runner with 275,000 does the same thing.

 

[philter]

If this is that easy, then perhaps I could do this swap https://www.fjrforum.com/forum//index.php/topic/157786-final-drive-swap-6th-gear-solution/ myself and save the 300 bucks, just buy a venture final drive off ebay??

 

[road runner]

Well this is a timely thread, thanks for starting it. I have an 07 with 114000 miles and have noticed a lot of play in the drive line for the last 2 years. I have a spare rear diff off an 05 FJR (mileage unknown), that I'm going to re-shim and put on my bike. Before I took it apart I checked the back lash and preload/rolling torque. I found the back lash to be very loose at .045" and preload snug @ 5in.lbs.

Took it apart and found the gears and bearing all look great, but it does need to be shimmed. I found a .60 mm shim (correction a .40 and .25 mm shim) and a 1.8 mm thrust washer locating the ring gear. All the preload was on the ring gear with no preload on the pinion. (which mean the thrust washer should have been a 1.6 mm) The FSM doesn't say they want preload, but it does say they want .1-.2 mm clearance on ring gear to thrust washer.

I need to tighten up the back lash and open up the clearance on the thrust. I can't get it perfect because of thrust washer sizes available, but can get it a lot better. Ideally I'd like to add .80 mm shim to gear making back lash .014" and take away 1.0 mm from thrust washer making .10 mm clearance by installing a .80 mm thrust washer, but that size washer is not available. So I'm going to add a .50 mm shim, which will change the back lash from .045" to .025". That is only if changing shim size is linear with back lash change. Then change the thrust washer from 1.8 to 1.2 mm (smallest avail.) . I'm adding .5 mm to gear and taking away .6 mm from thrust so it will lighten up the preload and maybe give some clearance, I wont know until I try.

I also have to check the stock rear diff that's on my bike now. Maybe I can get that one perfect. I wish there was more sizes available. I have parts on order and will chime in with results when done.

Just thought I'd chime in with my findings.
Ride Safe; Art

 

[AuroraTom]

On the dial indicator I was at .028--- spec is .010-.018. Noticable even when turning the shaft by hand can get a noticeable sound when the gears make contact.. When I tightened it up quieted it down a lot. The tolerances are understandably tight when new so no noise/ clunk isn't heard, but after 90k gears will wear and tolerances will open up.
As far as thinking it was shimmed before, I can't believe Yamaha factory would use 2 shims and on the FIsch the stock shim shows .40 mm. Mabey from the factory they used 2 shims, but I doubt it. And I can't believe a new final drive from the factory would have to be shimmed up that far.

I spent the day playing with final drive(s) and remembered this post.

I disassembled 2005 FJR and a 2008 RSV final drives. I'm planning to put the RSV gears into the FJR pumpkin so I can have an overdrive gear in my 2004 FJR. (10:33 vs 9:33 ratios)

Both of the final drive ring gear shims consisted of 2 piggy backed together. The FJR had a .30 and a .50 together (.80 total) and the RSV had a .25 and a .40 (total .65)

I don't think either of these final drives had ever been opened up so I guess the factory does regularly combine shims. These final drives were both from junk yards (mileage unknown on both).

When I checked the backlash both final drives were out of spec. The 2005 FJR measured .022 and the 2008 Venture was .030. My 2004 FJR measures .018 (upper end of spec) with approx. 60k miles. I'm not going to mess with this one so I can easily go back to stock if I don't like the new ratio.

Caution: If you are increasing ring gear shims to decrease backlash the manual says to decrease the thrust washer thickness. It would also be a good idea to check the stopper clearance because it will increase with an increase in ring gear shimming. I'm not sure what the correct clearance is. One of my POS manuals says .012 to .024 and the other says .010 to .020. Probably not critical. Also the stopper bolt is left hand thread (as is the pinion bearing retainer).

Tom

 

[Canadian Steve]

Just to add my 2Cents .

I have never opened up an FJR drive but have messed with Concours a little.

However I did at one time build diffs and trannies for class 8 trucks, and did many Toyota diffs installing lower gears and lockers. The principles remain the same.....

If a backlash setting was originally in spec and over miles has went out of spec (as mentioned above ,010 above max backlash), This is usually a sign that bearings need to be replaced. Tightening up specs by shimming alone on old bearings will in my experience lead to failure of that drive in a shorter time period than if it was just left alone. Most backlash increase comes from bearing wear, however a ring and pinion will develop wear, and getting a proper mating mark(most important for life of gear set) does not always mean the ideal paper spec. Looser is always better than tighter if going outside of spec.

Often when just tightening up backlash with old bearings a gear whine will be the outcome. Tightening up pinion bearing spec with old bearings will result in bearing failure sooner than later.

Also just recall that the dreaded BMW rear drive failure was imo mostly caused by to tight bearing preload setup from factory. (My old K1200LT did not suffer this issue (I checked) but many were wrong from the factory.

Maybe..........some FJR drives were set up to loose from the get go. .010 is a big increase in such a small gear set.

 

[AuroraTom]

Just to add my 2Cents .I have never opened up an FJR drive but have messed with Concours a little.

However I did at one time build diffs and trannies for class 8 trucks, and did many Toyota diffs installing lower gears and lockers. The principles remain the same.....

If a backlash setting was originally in spec and over miles has went out of spec (as mentioned above ,010 above max backlash), This is usually a sign that bearings need to be replaced. Tightening up specs by shimming alone on old bearings will in my experience lead to failure of that drive in a shorter time period than if it was just left alone. Most backlash increase comes from bearing wear, however a ring and pinion will develop wear, and getting a proper mating mark(most important for life of gear set) does not always mean the ideal paper spec. Looser is always better than tighter if going outside of spec.

Often when just tightening up backlash with old bearings a gear whine will be the outcome. Tightening up pinion bearing spec with old bearings will result in bearing failure sooner than later.

Also just recall that the dreaded BMW rear drive failure was imo mostly caused by to tight bearing preload setup from factory. (My old K1200LT did not suffer this issue (I checked) but many were wrong from the factory.

Maybe..........some FJR drives were set up to loose from the get go. .010 is a big increase in such a small gear set.

Thanks for that info Steve!

It's my first time to open up the FJR pumpkin so all advice is appreciated. Especially the part about not trying to eliminate too much backlash. I did swap gears in a ST1100 about a decade ago and that one seemed a little easier to do. I was putting GL1500 gears into the ST1100 with trashed splines because of lack of Molly 60 paste. I checked that one with Prussian Blue and it was good on the first check using the ring and pinion shims that came with the GL1500 gear set. I probably got lucky on that one.

I did learn something interesting today. The parts fiche only shows 3 pinion shims available: .30mm (.012"), .40mm (.016", and .50mm (.020"), but when I measured the pinion shims in the 2005 FJR and the 2008 RSV I found they were .46mm and .55mm respectively (not even close to what is "available"). Then I remembered the "formula" in the Service Manual for determining shim thickness by using the numbers stamped on the outside of the final drive case, along with any numbers that might be written on the ring or pinion gears. When I entered these numbers into the formula I arrived at exactly .46mm and .55mm. Evidently all the "in between sizes are available to the people who assemble the final drives at the factory.

I wasn't planning on removing the bearings off the pinion shafts but it looks like I should so I can put the .55mm shim into the FJR pumpkin in place of the .46mm one (there is about .003 thou difference between these 2 shims). The pinion shim is between the gear and the bearing so the bearing has to come off to remove the shim. Hopefully I can remove and reinstall the bearing without damage since it is about a $60.00 part (I'm trying to keep the expenses down because I might not like the new gearing).

Tom

 

[AuroraTom]

I thought I should update this post and bump it to the top.

The pinion bearings came off the pinion shafts easily and the shims were swapped from the 9 tooth FJR gear to the 10 tooth RSV gear. Two things to note are:

1. The pinion assembly doesn't come out or go into the F-D as easily as some write ups would have you believe. I had to fab up a gear puller to remove the pinions. It does come out relatively easily that way.

2. Be careful with these pinion bearings! They have a split inner race and the balls will fall out if you're not careful. I did the work on the kitchen counter with an old towel under my work area.

To reinstall the pinion assy into the F-D housing it's a simple matter of leaving the pinion assy in the freezer for a few hours while the pumpkin simmers in the oven for a similar length of time. I used the lowest setting my oven could be set to of 200F. I'm sure it wouldn't hurt it to go higher but that worked fine at assembly time and less risk of me burning my fingers. Wifey just loved the smell of hot hypoid oil in the oven

. The pinion assembly (pinion, shim, bearing) simply drops into the F-D housing freely after the freeze / heat.

The shims from the FJR ring bearing (.81mm) were used with the RSV ring gear bearing and as luck would have it my backlash ended up at .013 thou. The original shims from the RSV ring bearing were .64mm. I assembled the ring assembly into the F-D housing to check the clearance of the thrust washer (current size is 1.6mm) with plastigauge. After using the oven / freezer trick to get the ring gear into the ring gear housing and then the entire ring gear assembly into the F-D housing the thrust washer clearance measured .004 thou. That is the minimum acceptable clearance so I have decided to not use a thinner thrust washer because the increments between the sizes is .2mm (.008 thou). The stopper bolt to ring gear measured .015 thou.

I am waiting for new o-rings and a pinion nut to arrive from parts fish.com (approx $20.00). I also ordered a 1.4 thrust washer and a .50 ring gear shim but I hope I won't need to use them. I decided to reuse my existing seals for the pinion bearing retainer and the ring gear cover since they look good and didn't appear to be leaking when I took everything apart. Now that I have the tools and knowledge of how everything comes apart it would be easy to change them if I need to in the future.

The only tool / supply item I needed to purchase was a Dana 44 spindle nut socket (OEM brand from Autozone $22.00) and some plastigauge (also AutoZone about $5.00 IIRC). I already owned a dial indicator with mag. base, a quality old school mechanical Starrett micrometer, an air impact w/ 22mm socket (pinion nut). The pinion bearing retainer (left hand thread) was so tight on the 2005 FJR F-D that I had to use the air impact to loosen it. I was afraid I might damage the removal tool but it handled the hammering just fine. The pinion retainer on the RSV F-D came off easily and didn't seemed to be torqued tighter than 40 or 50 ft lbs.

I also made my own "ring gear holder" bolt with a lathe and 14 x 1.5 die to hold the ring gear from rotating while taking backlash readings at the pinion coupler. I looked locally for a 14x1.5mm bolt but couldn't find one so I turned one down from a piece if round aluminum bar stock I had on hand. Not much torque is required for this, hand tight is all it needs to be.

If anyone needs more detailed info or pics let me know (I would also need to know how to post pics

)

thanks for listening,

Tom

 

[AuroraTom]

Parts arrived last Friday, I put the final drive together yesterday with new o-rings and new pinion nut. Today I installed the final drive and put rear wheel back on. I took it out for a short 40 Mile test drive, mostly city streets and a few back roads. A lot of starts and stops and a few brief medium speed runs (up to about 90 mph).

I am impressed! I thought I might not like it because 1st gear is close to what 2nd used to be but that was not the case. Taking off from a dead stop was not a problem, didn't stall even once. It probably helps that I am running the OEM tire size (180/55 ZR17) not the slightly oversize 190/55.

I think this will eliminate the occasional search for a higher gear when already in 5th. 5th gear now seems like an overdrive.

Comparing speedometer to GPS speed I seem to be traveling approx 6% faster than speedometer indicates. Before the switch I "think" I was about 4% slower actual than indicated. Calculated fuel economy will take a hit but I will be traveling about 10% more miles than odometer indicates (I think it was accurate before the final drive swap).

I think I'm going to like this mod a LOT. I'm looking forward to putting on more miles as weather allows.

I will report back if any problems surface.

Tom

 

[Kelvin]

Parts arrived last Friday, I put the final drive together yesterday with new o-rings and new pinion nut. Today I installed the final drive and put rear wheel back on. I took it out for a short 40 Mile test drive, mostly city streets and a few back roads. A lot of starts and stops and a few brief medium speed runs (up to about 90 mph).

I am impressed! I thought I might not like it because 1st gear is close to what 2nd used to be but that was not the case. Taking off from a dead stop was not a problem, didn't stall even once. It probably helps that I am running the OEM tire size (180/55 ZR17) not the slightly oversize 190/55.

I think this will eliminate the occasional search for a higher gear when already in 5th. 5th gear now seems like an overdrive.

Comparing speedometer to GPS speed I seem to be traveling approx 6% faster than speedometer indicates. Before the switch I "think" I was about 4% slower actual than indicated. Calculated fuel economy will take a hit but I will be traveling about 10% more miles than odometer indicates (I think it was accurate before the final drive swap).

I think I'm going to like this mod a LOT. I'm looking forward to putting on more miles as weather allows.

I will report back if any problems surface.

Tom

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