kamalv Posted May 12, 2016 Share Posted May 12, 2016 Hello all. I just had new tires put on the FJ. The guy who does it is a friend, an older mechanic who has worked on BMWs for a long time. He raised a potential flag, according to him, about the coupling dog bone(?) and its bushing that connects the rear shock to the swing-arm. He showed me on my bike that when put on the center stand and he gently pushed under the rear wheel, there was play at the coupling piece(that is at the tail end of the rear shock) and it was rotating a bit instead of compressing the shock. This should not be the case in his experience. Told me to show it to the dealer, and I will be doing that this Fri. And he said the bolt on the side was loose which is what was allowing that movement. I was curious if anyone else knows more about this. The bike has just over 12K miles on it. I just had the stock tires replaced and did the usual assortment of maintenance stuff. I have been riding it daily until last weekend, and did not notice anything in the handling or any kind of chatter or what not. Not sure what it is that I would notice in the first place. Any input would be great before I go to the dealer. Thanks! Link to comment Share on other sites More sharing options...
skipperT Posted May 12, 2016 Share Posted May 12, 2016 Pretty typical across a lot of sport bike-type suspension models. Mine had that much play out of the crate. I wouldn't worry about it. Realistically once you are on the motorcycle that play would never be noticed. Yamaha does recommend they be checked every 8k. Typically I repack/lube them every 16k when I pull the swing arm to repack/lube those bearings. (The interval on the FJ is 32k for swing arm bearing repack) It's basically a bushing that rides on needle bearings, protected usually by a dust seal. The bolts that secure the dog bones/linkages all together with the shock/swing arm components in the rear end are inserted through the center of those bushings. Most beemers don't have traditional suspensions like our bikes, so this style may be a bit unfamiliar to him. -Skip Link to comment Share on other sites More sharing options...
kamalv Posted May 12, 2016 Author Share Posted May 12, 2016 Thank you for that info @skipperT ! That is reassuring. I didn't ride the FJ to work today out of an abundance of caution. You have described exactly what he told me. I will swing by the dealer tomorrow and hopefully the guy will be nice and indulge me for a few minutes to be absolutely sure. I will update after that. Link to comment Share on other sites More sharing options...
thruster8999 Posted May 12, 2016 Share Posted May 12, 2016 Hello all. I just had new tires put on the FJ. The guy who does it is a friend, an older mechanic who has worked on BMWs for a long time. He raised a potential flag, according to him, about the coupling dog bone(?) and its bushing that connects the rear shock to the swing-arm. He showed me on my bike that when put on the center stand and he gently pushed under the rear wheel, there was play at the coupling piece(that is at the tail end of the rear shock) and it was rotating a bit instead of compressing the shock. This should not be the case in his experience. Told me to show it to the dealer, and I will be doing that this Fri. And he said the bolt on the side was loose which is what was allowing that movement. I was curious if anyone else knows more about this. The bike has just over 12K miles on it. I just had the stock tires replaced and did the usual assortment of maintenance stuff. I have been riding it daily until last weekend, and did not notice anything in the handling or any kind of chatter or what not. Not sure what it is that I would notice in the first place. Any input would be great before I go to the dealer. Thanks! I have the same play as you do. Most people say its not a issue but I have to disagree. It shouldnt be like this at all. Link to comment Share on other sites More sharing options...
timg Posted May 12, 2016 Share Posted May 12, 2016 Unless there is a press fit between the hole and bushing, and the bushing and bolt, there will be a certain amount of play in the assembly. And you do not wan to pay for the precision sizing required for a press fit, I've worked in manufacturing quality for a long time and I've seen the quotes for this. Link to comment Share on other sites More sharing options...
xlxr Posted May 13, 2016 Share Posted May 13, 2016 ...."and it was rotating a bit instead of compressing the shock." What was rotating a bit? Do you mean there was some free play between the linkage arm and the bolts that go through the rear shock mount and dog bone connectors? That is normal, just cheaper to not make bolts machined to tighter tolerances. The problem occurs if the bolts get worn down or if the inner bearings/sleeves in the linkage arm wear out and get too lose or freeze in place. Link to comment Share on other sites More sharing options...
timg Posted May 13, 2016 Share Posted May 13, 2016 ...."and it was rotating a bit instead of compressing the shock." What was rotating a bit? Do you mean there was some free play between the linkage arm and the bolts that go through the rear shock mount and dog bone connectors? That is normal, just cheaper to not make bolts machined to tighter tolerances. The problem occurs if the bolts get worn down or if the inner bearings/sleeves in the linkage arm wear out and get too lose or freeze in place. And I'm confident Yamaha has run and analyzed many hours of simulated extended life reliability testing on this type of assembly, so we can all sleep well and dream of fantastic roads and good weather, with little drooly smiles. Oh yeah. Link to comment Share on other sites More sharing options...
kamalv Posted May 16, 2016 Author Share Posted May 16, 2016 Thanks all for the input and feedback. I took it to the dealer and did my best to explain it to him. He perfunctorily tried to move the rear wheel on the center stand for about 10 secs and said he doesn't really know. The offer then was to check it into the shop and leave it there. Since that is a potential sinkhole for the dollars, I figured I will get back to riding it every day and see if I notice anything. Since this flag was raised when I had new tires put on it, the only sensations I am noticing is excellent feedback and traction from the new Metzler Roadtec 01s. While some of it is the new tire effect, the grip in the wet and dry feels sincerely amazing to me. And I have ridden the usual touring tires PR3 and 4s on other bikes as well as the stock Dunlops on this one. Recently had Dunlop Sportmax Q3s put on a different one and even the feeling with that new set doesn't compare to the kind of road feedback I am getting with these Metzlers. And it has rained for two weeks continuously around here in DC. So its been a decent test while brand new. Will see how long this lasts. Link to comment Share on other sites More sharing options...
bruceintucson Posted May 23, 2016 Share Posted May 23, 2016 My '03 FZ-1 has the play as well, as does the new FJ-09. Contacted a friend who was a SM for a multi-line Dealership in TN when I bought the FZ-1 used about 6 years ago. He said it's normal, though my '96 VFR750 with almost 100K miles doesn't have any. :-) Link to comment Share on other sites More sharing options...
phm14 Posted April 8, 2017 Share Posted April 8, 2017 I noticed this bushing play in my 1st year production FZ09. Yamaha USA said it was "normal", but I personally don't like it. It may only come into play while the suspension is at full droop, at or near the point of breaking contact with the ground. I've seen Isle of Man video of bikes landing from airborne while on throttle, and crashing from speed wobble. Not saying this shock play would cause or contribute to this scenario, but I'm fairly sure it wouldn't help. Who knows? I've been wrenching cars and bikes for 45 years and have never seen suspension play like this unless there were worn parts that needed replacement. Link to comment Share on other sites More sharing options...
motocd Posted April 8, 2017 Share Posted April 8, 2017 The lower shock mounting clevis clamps via the through bolt onto the hardened pin. The pin rides in a needle bearing. There should be very little play but all the bearings in the system are additive and compounded at the rear wheel due to the suspension motion ratio. I would move the wheel in the way you are testing but place a finger on the specific joint. The clevis is locked to the pin with no relative motion with the hardened and ground pin rotating inside the bearing. There will be very little radial clearance and more side to side clearance. It would be very easy to remove the lower shock mount, swing up the shockand pull the pin to inspect the bearing and pins condition. Link to comment Share on other sites More sharing options...
Premium Member 2and3cylinders Posted April 9, 2017 Premium Member Share Posted April 9, 2017 Kam Mow I've got to check this out, thanks (but maybe ignorance is bliss but having to clean and lube the sing arm and linkage every 16000 miles for mean meand at least once a season which seems excessive. BTW, from where and for how much did you get the Metzelers? The was/is a $40 rebate debit card deal from Metzeler Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.