'06 excessive driveline lash

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I'll post...but this is going to cost you kids. Check the torque(fjrchik doesn't know what this means) on your rear wheel. Make sure it's connected together correctly. The bad thing is....it's between two gears. Were you going the same speed when you had this prob? Try the same corner at a slower speed....a faster one...if it won't kill you.....if it's between the same gears...go get a new transmission gear. I am sure if you are the white pasty faced clown that we all are that you got a warranty on the scoot. Oh, and get ready for more clown acts....we have plenty of them in here. I am just an understudy to radman...even though he doesn't know about it. :blink:

 
I compared my 06FJR with my properly adjusted chain driven Aprilia Tuono and noticed no discernable difference between the two bikes with respect to driveline lash. The Tuono is very smooth during throttle transitions. With the FJR I do experience the same problem in throttle transitions that others have reported. I attribute it to two factors, one is abrubt throttle response and the other is excessive throttle freeplay. I have taken ALL of the freeplay out of the throttle and adjusted the CO settings and that helps but it is still not as good as it could be but it is quite a bit better than it was.

 
Have you released the center throttle spring?

80% of what your describing goes away with that mod. It was pretty funny to see me unsuccessfully trying for smooth shifts with that tight ass cable. Now that its loose (or correct), i have to relearn how to shift "the way your suppose to".

Took me damn near 5 minutes to get it right. What a difference. I just cant believe it. Still not perfect in the first couple of gears, but hope is in sight.

Greygoose

 
Have you released the center throttle spring?
80% of what your describing goes away with that mod. It was pretty funny to see me unsuccessfully trying for smooth shifts with that tight ass cable. Now that its loose (or correct), i have to relearn how to shift "the way your suppose to".

Took me damn near 5 minutes to get it right. What a difference. I just cant believe it. Still not perfect in the first couple of gears, but hope is in sight.

Greygoose
+1 Greygoose. I think you've touch on a nerve to the problem. I've experienced similar problems with the shifts. I definitely need to do the spring alteration and one thing I've found to help with this matter is when shifting, don't mess around taking your time to shift either. Coming off a big twin, this is an old habit to break. Make the shifts now with minimal time between gears. Hey what can I say, its a zoomie. PM. <>< :D

 
Adjusting out the factory provided 1/4 " throttle cable slop, and backing off the center throttle return spring 1 revolution eliminated the problem for me. Since making the adjustments, I can still generate some lurch if I'm getting sloppy on the throttle, but when I'm in the groove, finesse counter steering and dialed in throttle input, it's not noticeable and doesn't unsettle the chassis through the turns.

 
Basically it's when you get back on the throttle after rolling off... and instead of a smooth transition from off throttle to on, you get an abrupt one that causes the trans (shaft) to "hit" or "whack" the driveline... not just spool up. There can be an audible sound, or a feeling thru the seat and pegs of a "thump" in the driveline the instant that power is being reapplied to the rear wheel. It's not "surging" as some here have stated- that's more of a feeling of intermittent or unbalanced fuel delivery that causes the engine to stutter (usually inaudible, but you feel it "hunt" for the right fuel delivery). Driveline lash effects low speed driveability- imagine getting back on the gas at the apex of a hairpin turn and having a hit go thru the rear wheel, instead of smooth, controlled input of power. Not cool!~ I guess a TB sync is next... or maybe a dealer drop off for a couple of days. The thing with this bike is that NOBODY in this market seems to have any experience working on one. And the few dealers that I've heard of handling Yamaha in this market are not exactly known for great service depts. I'd love to solve this myself without a dealer if I can. Thanks for the help guys, I already feel like I'm narrowing this down some with your help.

After 1100 miles I can't say driveline lash has been a major issue for my '06....some shaft effect got me in a little trouble a time or two, but that was my fault. Just my experience thus far.

 
Using the ol' tape on the floor measurement method on #71 I get 2. 1863572 inches of movement (or 2 3/16ths if you just want to be close). :D

I went through my drive line this weekend becasue I didn't like a sound I heard at the car wash. I had it on the center stand running in first gear washing the rear wheel and I kept hearing a clanking sound. Really made me nervous. Turns out my neighbors '05 with 25k on it does the same thing. With no load on the drive line you can just "hear" the gear lash. I went ahead and investigated anyway. Added a little extra grease to the splines on the drive shaft and wheel gear. Also put Red Line gear oil in the rear end. But I have to say, the TB sync, removing the center spring and adjusting the slack out of the throttle cable made things much nicer.

 
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Adjustimg the throttle freeplay might have aggravated your problem. After riding my new 06 for a few days I started thinking that there was too much throttle freeplay so I adjusted most of it out. Big mistake. Now the bike lurches and the fuel injection is much jumpier off idle. What appears to be excessive freeplay might actually be part of the Yamaha's design to lessen the jerkiness. Try going back to the original freeplay and see if this cures the problem.

My 98 VFR800 had a similar problem: excessive throttle jerkiness that made the bike a handful in corners. It was easily to cure this problem . I simply adjusted the idle up 300 rpm and the jerkiness simply disappeared.

If adjusting the original slop back into the throttle doesn't cure your problem, try adjusting your idle up a few hundred rpm.

I have been told that injection jerkiness is often the result of the idle being set to minimize pollution during government testing rather than to enhance the performance of the bike.

 
Several posts have nailed it. To summarize:

1) Adjust all the slack out of the throttle cable. It WILL help!

2) Do the jumper mod and bump up the CO settings (5 worked fine for me). If you worry about warranty, put the wires back to original spots after the CO settings are made. No one will know the diff.

3) Release the tension on one or two return springs

4) Now get some riding in and adapt.

Given these steps you should find te FJR to be MUCH smoother. Now a couple other ideas:

5) Lube the shaft with moly, and

6) (god, I hate to even bring it up, but ...) switch to synth in the crankcase.

These two changes also made a big improvement in overall shifting and driveline response.

Lastly, keep in mind the FJR throttle plate/cam is progressive and has damn little travel. It will alsways have a sportin' nature.

If you really aren't satisfied after the above easy mods, look at Fred H's post on the throttle cam issue.

For me, I don't feel the need to get jiggy like Fred did, as the mods and adjustments I noted transformed the bike for me.

 
Well, I picked up my '06 last week in Ohio and rode home to Maryland the curvy way... and all was right with the world. (except for some loose steering head bearings :angry: ) but now that the bike is getting some miles on it (2300 in 9 days- not bad)... I have developed an excessive driveline lash that makes the bike a real handful in the twisties. I have adjusted the throttle cable tension three times with little effect- now I'm trying some Redline Shockproof heavy gear oil in the final drive- I've had great results with Shockproof heavy in my BMW's in the past. Has anybody else experienced SERIOUS driveline lash- and what have you done about it??? I love the bike- but this is just nuts! I've had three people ride it and all have commented on the lash effect and how unsettling it is- They should have been at Deals Gap on Saturday- Now THAT was unsettling!~ 2nd gear throttle on/off is like taking your life in your hands when the road is that tight!
Thanks for the help folks- Love the forum! sorry that my first post was a problem with my brand new scoot!
Jabba... I think I may have posted about the same/same deal with the "on/off/on" throttle control before. And, like you, this ain't my first motorcycle. Shaft drive, FI, and some power is not new either. My GL1800 WING is smooth as silk in the on/off/on throttle used in cornering.

Yeah, I know, I know... Big WING is a POS and the FJR is just the cat's meow. And, I suppose that riding many different MCs since the 60s don't count either. And, "just get used to the bike, dude!". Whatever.

There really IS an uncomfy feeling when you back off the throttle and get back on it. Supposedly, I had the dealer's tech do the middle spring/Barbarian jumper mod/CO adjustment. I found ZERO difference in anything I experienced before. Soooo... I believe they just jerked me around (didn't charge me, tho) and said they did these mods. The tech was not to keen on doing them anyway.

I'm gonna take some of the HUGE slack out of the throttle cable today. Then, when I get some guts (and a low gas tank), I'll try to see for myowndamnself if they did the throttle/jumper mod. Since it's been raining here in New England FOREVER!, it could be some time before I can ride the FJR and see if these mods make a difference.

I do find it odd that some folks think nothing is wrong with the bike as it comes from the factory? The FJR would be the first bike I've had to modify to ride technically. Making saddle changes, adding grips, a backrest.... well, this is to be expected from an ergo standpoint. But, screwing with the mapping, throttle springs, installing a Commander? I think this is not what I expected. I agree with Jabba. :(

BAGGER

 
I have over 500 miles on the bike since I modified the throttle pulley.

I have had zero problems with it, and the difference is like night and day. What I thought was drive line lash turned out to be caused by the too sensitive throttle. The bike is smooth as silk now, and I am really glad I did this modification. It has made a world of difference. The bike is so much easier to ride in a relaxed manner and take much less effort to be smooth in the tight stuff.

 
I have never ridden a 06 but all the FJRs seem to have a sensitive throttle.

Just like others said;

FJRs have a lot of torque and a sensitive throttle. The shaft drive has 2-3" of play (movement back and forth in gear).

All this attributes to how the bike rides. Not necessarily a defect, just the nature of the beast.

 
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I have never ridden a 06 but all the FJRs seem to have a sensitive throttle.
If you get a chance to ride an 06, I would like to hear how you think the low rpm throttle response feels in comparison. I suspect you are in for a rude suprise.

 
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I have never ridden a 06 but all the FJRs seem to have a sensitive throttle.Just like others said;

FJRs have a lot of torque and a sensitive throttle. The shaft drive has 2-3" of play (movement back and forth in gear).

All this attributes to how the bike rides. Not necessarily a defect, just the nature of the beast.

Well, if you are correct that they're supposed to be this way, then it is a defect- in the design of the beast. Listen, low speed throttle modulation is key to rideability. That's just part of building a great motorcycle- you nail the driveline issues or you catch hell for it in the press and it effects your sales. It's even more critical when the bike being designed is gonna have 146 HP! I'm perfectly willing to believe that it's just a tuning issue and that it's related to some government requirement out of the box- and i'm working to tune the problem out of the bike. If it ends up that the bike is designed to have an abrupt on/off throttle response, it's gonna morph into some other brand- something with better rideability. And that's not because I don't know how to ride, it's because I DO know what good motorcycle design is and what is a flaw.

 
and i'm working to tune the problem out of the bike.
Jabba,

Yamaha changed the throttle pulley in 06, and made it have a progressive pitch, which makes small throttle movements at just off idle have a larger effect on the throttle bodies.

I put a shim under my throttle pulley and it completly and totally eliminated the jerky throttle response. The bike is now smooth as silk at all RPMs and speeds. I can ride circles in a parking lot at 10mph with no jerky throttle inputs and can make throttle adjustments mid turn in tight corners without the jerkyness it used to exhibit.

I posted some photos of what I did in this gallery if you want to see it.

https://www.pbase.com/fredharmon/thottlepulley

 
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I'm not questioning your ability Jabba. Maybe the 06s have a problem.

If they are the same as previous though, I don't see the problem.

I'm going to try and find an 06 at a dealer for a test ride and see what everyone is talking about.

 
One small shim is all it takes to fix this.

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