ES Forks - Possible design issue w/excess play

[RaYzerman19]

A UK rider with a 2013 AS (with ES), mileage 8k, has asked for assistance with a potential design issue. He has not been able to cure a front end shimmy or wobble issue with the normal fixes of checking steering head bearings per FSM, front end assembly, new set of tires, rebalancing, etc. Dealer has only the same recommended fixes. He removed the front wheel and fender, and when the forks are extended, discovered play (any lateral direction) of 1mm on one side and 1.5mm on the other. The dealer did the same to a brand new ES, and got 1.5 & 2mm play. Consultation with Yamaha Tech..... they said the service limit is 4mm.

Note, the FJR ES forks do not have bushings, but rely on the inner and outer fork tube sliding with each other. Comparison was also made to a Super Tenere ES, which has bushings, and the play is not evident. To repeat, this is with front wheel and fender removed, forks extended via the springs. If checked while wheel on ready to ride, the play is not detectable. Makes sense, axle/spacers/wheel is all captured to prevent side to side movement, forks now bound as a pair, and likely weight is too much to overcome easily to detect fore/aft movement.

My thoughts - More info required, i.e., remove the springs (leave oil in, perhaps compensate for no springs by adding oil) so more measurements can be taken at various engagements of the inner and outer tubes. It will be worst when fully extended and likely be progressively smaller as the forks are "compressed". The tubes will ride on a film of oil, as do bushed forks, and perhaps measurements should be taken without oil as well (if it were me, I'd just want to know, plus would like Yamaha Tech to know/check also). There is likely to be more play with no oil. I'm thinking if anyone is due for a tire change soon, perhaps someone would like to investigate further.

Back to the shimmy problem (hands off handlebars), I don't think technically one necessarily follows the other... is this play issue a problem or not, who knows at this point. I'm sure you folks will have some more thoughts........

 

[Intech]

Well, I have been experiencing the same issue with my '15. It is primarily at speeds below 40 MPH. It would get violent if I let it continue for more than a couple seconds. I have checked all the things Ray mentioned, but not freeplay with the wheel off. I replaced the stock tires at just under 1200 miles and have almost 10k on a set of PR2's. Honestly, I didn't think anything of it until reading this post. I have had a wobble on the '07 that came and went with tire changes, so really put it out of my mind until I changed tires again. this has me concerned. I will be interested to hear other ES owners chime in.

 

[El Toro Joe]

[email protected] I won't be buying a 2016 ES.

 

[Intech]

[email protected] I won't be buying a 2016 ES.

Don't jump to conclusions based on 2 bikes. If it was really a prevalent problem I would think that there would have been a lot more chatter on this by now. After all the ES has been on the market for 2 model years now. The source of the bike first mentioned here may be something completely different than mine.

 

[rickysnickers]

Is there a way to fit a steering stabilizer to the bike, like an Ohlins or Hyperpro?

 

[HotRodZilla]

Haha...ES losers. :fuck:

Oops...I mean, darn, that's terrible!

 

[Intech]

Haha...ES losers.

Oops...I mean, darn, that's terrible!

And you have the nerve to call someone else a dick?

 

[RaYzerman19]

I'll make the same offer I made to the UK guy..... send that POS to me and I'll ride it for a few years and letcha know how it turns out...........

No sense jumping to any conclusions, we haven't proven it's a problem yet. I will say I wondered way back why the forks didn't have bushings, but what good USD fork doesn't have bushings. Do we know of another without bushings? I did work on a conventional fork (sorta) BMW LT that didn't have bushings, but it was very precise fitting.

Questions to be answered - Once the wheel/axle/fender is all bolted up, and eliminated the side play, and now joined up both forks as a unit, how much play is really left? If the forks are compressed to the point of bike sag, how much play is there, or does it mostly disappear? Wish I had the design drawings, but I don't. I don't even have a FSM....... what does the FSM say with regard to 'wear limit', if anything? Hey, we're talking a 1-2mm play on a fork with nothing attached to it but its cartridge and spring guts. I suspect way less as you assemble everything...... so if it is half a mm what does that play do? How much play does a GenII have or one of those POS Gen 1's?

Joe..... probably should submit your order.

 

[Burnspot]

I noticed a hands-off shimmy as well...at low speed (as Bob observed). At highway speed, it's not evident. Not terribly concerned about this, just contributing as I ride with my hands on the bars. I'm still running an OEM front tire on the bike with 8300 miles on it and 40-42psi...it has not squared off and, quite frankly, still looks great. Never thought to try it on my '07, but I have to wheel it out for an annual state inspection this month, so I'll see what happens (it has AK20 fork innards).

 

[SkooterG]

Seems to me the solution is obvious: Don't take your hands off the handlebars! What am I missing?

Have had many a bike do it, or not do it, over the years. Mostly a function of tires in my cases, though loading/suspension has played a part too. In all cases, having both hands on the handlebars has made it a non-issue.

 

[wnyfjr]

Well, I have always noted (as have others here I believe) a 'hands-off' shimmy around 40-45 mph on my '06. I have experienced it with both new and worn tires. It has never concerned me, since I don't typically ride hands-off for more than a second or two. Now if the newly-reported symptom occurs with both hands on the bars at highway speeds, then you got something to look at seriously.

 

[wheatonFJR]

The only time I take my hands off the bars, is when I need to pound down a beer in a hurry...while sitting on the back seat with my feet reclined on the tank.

But otherwise hands on the grips at all times. Are you guys nuts?!

 

[Redfish Hunter]

Ray, we need a little more info on this "issue". Does this shimmy/wobble occur at low speed, high speed, or all the time? Does it happen under acceleration, deceleration, or at steady cruise speed? Lastly, is this the same "It wobbles when I turn loose of the bars" crybaby bullshit that we have heard off and on over the years?

When my ES was around 2K miles I read a complaint about the front end wobbling with the bars released on deceleration. I tried it with mine and it was smooth as butter, no wobble. By the time it reached 5K miles I could feel it pulsing gently on deceleration with my hands still on the bars (like they are supposed to be!). I tried releasing the bars on deceleration and yes, it wobbled like hell. I concluded that it was due to the wear pattern on the OEM Bridgestone, which actually looked pretty good. The rear OEM Bridgestone was almost done at 5K, thank goodness.

I put a set of PR4 GTs on the bike and that very strange PR4 front tire has caused a slight "wobble" at parking lot speeds. It goes away around 10 mph.

I put a little over 12K miles on my ES in the first year I had it. It has carried my fat ass and a full load of luggage and gear from the sea level swamps of Louisiana to the high passes of the Rockies. It has leaned over far enough to drag its pegs and erase its chicken strips. I have felt the ABS cycle while attempting (unwillingly) to do a stoppie.

To be blunt, any issues I have experienced with my ES have been TIRE issues. And to be mean about it, I could care less if the front end wobbles on deceleration with the bars released. Why would I EVER turn loose of the handlebars while decelerating?

 

[MCRIDER007]

No sense jumping to any conclusions, we haven't proven it's a problem yet. I will say I wondered way back why the forks didn't have bushings, but what good USD fork doesn't have bushings. Do we know of another without bushings? I did work on a conventional fork (sorta) BMW LT that didn't have bushings, but it was very precise fitting.

I wouldn't jump to the conclusion that the forks don't have a lower bushing even if it is not shown on the parts fiche. Kawasaki doesn't show lower bushings on the ZX-14 and C14 inverted forks but a pretty good source on the C14 forum said they are there, just above the oil seals, but are considered by Kawasaki to be lifetime parts so not included on the parts fiche. Since the top of the tube does not have have a bushing, it isn't necessary to remove the lower bushing to change oil seals. Granted, that is second hand into, but certainly makes sense from a manufacturing perspective.

I'm curious where the play is with the subject forks, is that with the forks still mounted in the triple clamps? If so, how do you distinguish between fork play and the play in the triple clamps bearings? 1.5mm of play sounds excessive and 4mm sounds off the chart....how could the oil seals not leak with that amount of play in the forks between the inter and outer tubes?

My experience with my 14ES is that I have a shimmy that starts at 45mph on a hands off coast down and gets uncontrolable by 40mph. However, there isn't any shimmy below 40mph. I thought it was due to the OEM BT023 tires but the shimmy was only slightly less severe with the replacement BT023 tires. So, zero shimmy above 45 or below 40...I think it is the tires and am not going to worry about it.

 

[Intech]

The front end of a motorcycle natural wants to wobble due to rotational forces. The design of the front ends on modern bikes negates most of that influence, however it doesn't take a whole lot to cause the head shake.

The only time I take my hands off the bars, is when I need to pound down a beer in a hurry...while sitting on the back seat with my feet reclined on the tank.
But otherwise hands on the grips at all times. Are you guys nuts?!

At what speed do you do this?

 

[Allen_C]

Like many others, I've tested this "hands off shimmy" with my '14ES the past 2 years. It does seem to be a tire related occurrence. With 34k mi on the odometer, I've gone through several tires and the best seems to be T30's. I've also tried the BT-023s (two sets) and Shinko 009 Ravens.

I've had the shimmy show up mostly between 42-49 mph. With the T30s, I really didn't experience any shimmy. With the Ravens, the shimmy was present from the beginning but only from 44-48 mph. With the BT-23s, they were smooth until about 2k in.

Regarding ever riding with your hands off, I only do this to test and simply keep my fingers around the grips but just not holding them. I check this because at the worst I've experienced, I can feel the shimmy a little when riding through fast sweepers - not a very reassuring feeling.

 

[TomInPA]

Like many others, I've tested this "hands off shimmy" with my '14ES the past 2 years. It does seem to be a tire related occurrence. With 34k mi on the odometer, I've gone through several tires and the best seems to be T30's. I've also tried the BT-023s (two sets) and Shinko 009 Ravens.
I've had the shimmy show up mostly between 42-49 mph. With the T30s, I really didn't experience any shimmy. With the Ravens, the shimmy was present from the beginning but only from 44-48 mph. With the BT-23s, they were smooth until about 2k in.

Regarding ever riding with your hands off, I only do this to test and simply keep my fingers around the grips but just not holding them. I check this because at the worst I've experienced, I can feel the shimmy a little when riding through fast sweepers - not a very reassuring feeling.

Thanks Allen. I was wondering why you're so slow.

 

[Intech]

I don't think I have ever felt a shimmy while riding. I also have never seen it above about 50. Easy to test on the '15 with the cruise control. I, like Allen, only just slightly release the bars to see the result. The slow speed head shake on the '15 can be controlled with 2 fingers. I have never tried it while accelerating or decelerating. That's just nuts. Suspension and tires are the biggest contributors to bad head shake.

 

[ionbeam]

...Suspension and tires are the biggest contributors to bad head shake.

Steering head rake, trail, ride height and suspension sag play a role too. (On the unchanged FJR steering rake, wheelbase, motorcycle weight, tire size and engine placement remain pretty much unchanged.) On decel there is weight transfer to the front end which changes the front geometry & weight carrying and how you have your suspension setup will cause different results (including different rider weight and cargo weight). And yes, tires too