Lo RPM Roll-On Odd Engine Vibration

[benneyb]

A question for you longer term owners: I notice an odd engine vibration when rolling on starting from less than 3k rpm with 1/2 or greater throttle. I know, the quick answer is don't roll-on until over 3k, and I usually don't. I'm just wondering if something might be wrong?

It doesn't last long, maybe for a 200 rpm span or so crossing over 2900-3000, and feels like its coming from the center - rear of the engine.

Anyone else notice this?

 

[Toecutter]

If you've added Moko's (and maybe even if you didn't), the motor mount bolts could be loose.

 

[benneyb]

Toe,

Good tip. The previous owner did install sliders - I'll check 'em.

Thanks!

 

[kaitsdad]

Yep, good call TC !!

Bennyb, back off on both left and right side - then torque the left side first.

 

[kingoldrum]

Same issue as BennyB. Low rpm acceleration causes rumble/shudder in rear of engine (or drive?). 06 with no mods and 1600 miles, but I will check the mounts as suggested. Seemed worse 2 up. This is a bit of a "lugging" condition, but certainly one the fjr should handle without downshifting. I rode an 03 and never felt this. Anyone else resolve this? Would love to go to the dealer with some specific action for them.

 

[slapnpop]

IMHO, it sounds like the engine bogging from too much throttle at a low RPM. You SHOULD down shift at this point, or use much less throttle. If you aren't in enough of a hurry to downshift, you're not in enough of a hurry to require 1/2 throttle.

One of the experts may chime in to correct me, but I understand this to be hard on the engine as well, inflicting the most wear of any operating conditions (short of abuse).

 

[S76]

Mine does the same exact thing, 2500 to 3000 RPM range. There is nothing wrong, really. It's just a harmonic in the drive train and you are feeling engine power pulses due to the low RPM. Mine did it more when it was new but now at 6K I don't notice it much at all. Or...maybe I just got used to it, or maybe subconciously I avoid doing that. Not sure, but it's OK.

 

[skyway]

IMHO, it sounds like the engine bogging from too much throttle at a low RPM. You SHOULD down shift at this point, or use much less throttle. If you aren't in enough of a hurry to downshift, you're not in enough of a hurry to require 1/2 throttle.
I understand this to be hard on the engine as well, inflicting the most wear of any operating conditions (short of abuse).

Agree, downshift, its not an automatic.

 

[kingoldrum]

I expect that most fjr's don't do this or we would hear more comments. Does not seem to be that unusual of condition, coming out of a corner in 3rd gear, 32mph and wanting to get back up to speed. No previous bike I've owned protests so much down there (including an '83 CB650 shafty). I expect that something is up.

 

[user 254]

Mine does it too. Like S76 I figured it was harmonic's and I should have downshifted. Mine got better after a FI sync.

 

[jjsC6]

Mine does it to ('06).

 

[Ignacio]

Had it happen to me too. Lugging engine.

Let off gas, downshift, resume accelerating to warp speed. Fixes it every time.

 

[benneyb]

I've been delinquent in responding to my own thread!

I did retorque the engine bolts some time ago - no effect. Like most of the others here, I've just been more careful with the throttle in that rpm range, so as not to strain the motor.

 

[TestPilot]

I expect that most fjr's don't do this or we would hear more comments. Does not seem to be that unusual of condition, coming out of a corner in 3rd gear, 32mph and wanting to get back up to speed. No previous bike I've owned protests so much down there (including an '83 CB650 shafty). I expect that something is up.

No, wrong expectation. The correct expectation is that most FJR owners don't come out of a corner in 3rd gear at 32mph and expect the motor to pick up when opened to half- or greater throttle. If you're going to use that much throttle, use a lower gear. Far less strain and wear on the motor.

BTW, there is a 'no-clutch-lever' version for those too lazy to ride properly <_<

 

[Ari Rankum]

IMHO, it sounds like the engine bogging from too much throttle at a low RPM. You SHOULD down shift at this point, or use much less throttle. If you aren't in enough of a hurry to downshift, you're not in enough of a hurry to require 1/2 throttle.
One of the experts may chime in to correct me, but I understand this to be hard on the engine as well, inflicting the most wear of any operating conditions (short of abuse).

Agree. The only time you must travel through 3K rpm is in first (actually, if you can handle wheelies okay, you don't even have to do it in first). Otherwise, downshift to keep the RPMs up, and you won't be lugging the engine.

 

[spklbuk]

A question for you longer term owners: I notice an odd engine vibration when rolling on starting from less than 3k rpm with 1/2 or greater throttle. I know, the quick answer is don't roll-on until over 3k, and I usually don't. I'm just wondering if something might be wrong?
It doesn't last long, maybe for a 200 rpm span or so crossing over 2900-3000, and feels like its coming from the center - rear of the engine.

Anyone else notice this?

I too am a short term owner and mine has done it too, esp. 2 up. I attribute it to coming from cruisers with their low and mid-torque and crappy way too quick rpm limiters that kick in just when its getting good. Bennyb are you coming from a cruiser as well? It's taking me some time to get used to having a broader effective rpm range, but damn sure havin' a good time learning. Gearing down to keep the power band up and smooth based on the way she feels is slowly becoming second nature and such vibes are becoming less of an issue. Ride 'er some more... and I hope I can heed my own recommendation.

 

[benneyb]

No, no cruiser for me. I'm coming out of motorcycle deprivation for the past 13 years.

Before that most recently I had a sportbike, a 750 Ninja.

I think I was used to driving cars with the resulting much lower rpm response and usage, and initially expected it to carry over to the FJR.

 

[kingoldrum]

Have been keeping the rpms up so things are OK. I am coming off a 1100XX and in retrospect, it would protest too if I was lazy and hadn't downshifted. The FJR protest is more disconcerting I guess. Will keep up the rpms.

Thanks

 

[Dan23]

FWIW, mine does this too. I merely downshift before accelerating or ease into the throttle.

I thought it was an EXUP valve opening, but not sure a. if the bike has one and b. if that'd be the rpm range it opens (or does it close)? In any case, my take on it is that it is due to exhaust harmonics or reversion. Does not feel mechanical in nature to me.