EVO Custom Low Rider Vibrates : V-Twin Forum: Harley Davidson Forums

Bluesman · 09-12-2007, 02:04 PM

I have a FXLR Custom Low Rider with the EVO engine.
The bike has ran great for me but about a month ago I noticed
a vibration when in 5 gear and running at 50 to 60 mph
The bike has always had a light vibration at 2000 rpm but never at 2800/3000 rpm
Just for input all mounting rubber is new as of last year that includes
new Progressive rear shocks and front springs.
The bike starts and runs nice and all works well.
I would like input on what possibly could cause the problem.
I did take the bike to the local Harley Dealer and the service Mgr rode the bike
and said "Yep she vibrates starting at 50 to 60 MPH"
But they did not have an answer as to what was cousing the vibration.
Thanks for any help.

84FXRP · 09-12-2007, 11:54 PM

Quote:

Originally Posted by Bluesman

I have a FXLR Custom Low Rider with the EVO engine.
The bike has ran great for me but about a month ago I noticed
a vibration when in 5 gear and running at 50 to 60 mph
The bike has always had a light vibration at 2000 rpm but never at 2800/3000 rpm
Just for input all mounting rubber is new as of last year that includes
new Progressive rear shocks and front springs.
The bike starts and runs nice and all works well.
I would like input on what possibly could cause the problem.
I did take the bike to the local Harley Dealer and the service Mgr rode the bike
and said "Yep she vibrates starting at 50 to 60 MPH"
But they did not have an answer as to what was cousing the vibration.
Thanks for any help.

Has the vibration gotten progressively worse? Or was there a sudden on set of vibration at 2800/3000 rpm?

Is the vibration associated with a particular speed or with a particular rpm?
That is do you have the same vibration at 2800/3000 rpm in 4th gear as you do at 2800/3000 rpm in 5th gear? Or do you notice the vibration at 50 to 60 mph regardless to the gear you are in? Does the vibration abate when you pull in the clutch?

Have you checked the tightness of all the engine mount fasteners?

Does the bike track straight?

Do you have spoked or cast wheels? Any loose spokes? Any damage to the wheel?

Lost any wheel balance weights?

Where do you notice the vibration? (handlebars, seat, foot peg, etc)

Are all the exhaust pipes properly aligned with the fasteners tightened? Any interference with the exhaust system and the frame of the bike?

Bluesman · 09-13-2007, 05:01 AM

To 84 FXRP
Has the vibration gotten progressively worse? Or was there a sudden on set of vibration at 2800/3000 rpm?
ANSWER: THE VIB JUST STARTED LIKE ALL AT ONCE

Is the vibration associated with a particular speed or with a particular rpm?
That is do you have the same vibration at 2800/3000 rpm in 4th gear as you do at 2800/3000 rpm in 5th gear? Or do you notice the vibration at 50 to 60 mph regardless to the gear you are in? Does the vibration abate when you pull in the clutch?
ANSWER: THE VIB IS MUCH STRONGER AT 55 MPH IN 5TH GEAR
YES WHEN I PUT IN THE CLUTCH THE VIB STOPS

Have you checked the tightness of all the engine mount fasteners?
ANSWER: THE FRONT IS NEW/RUBBER MOUNT THE REAR DONT KNOW

Does the bike track straight?
ANSWER: YES

Do you have spoked or cast wheels? Any loose spokes? Any damage to the wheel?
ANSWER: FRONT SPOKE REAR CAST

Lost any wheel balance weights?
ANSWER: NO

Where do you notice the vibration? (handlebars, seat, foot peg, etc)
ANSWER: FOOT PEGS AND HANDLEBARS THE SEAT I DONT NOTICE

Are all the exhaust pipes properly aligned with the fasteners tightened? Any interference with the exhaust system and the frame of the bike?
ANSWER: THE EXHAUST IS IN FINE SHAPE ALL ALINGNED AND TIGHT NO INTERFERANCE.

ONE LAST BIT OF INFO THE VIBRATION STARTED ABOUT THE SAME TIME MY TRANNY WAS OVER FULLED
TO THE POINT THAT LUBE WAS COMING OUT THE SPLIT HALF. ALL LUBE WAS DRAINED AND FILLED
TO THE PROPER LEVEL. DONT KNOW HOW THAT COULD CAUSE THE PROBLEM.

84FXRP · 09-13-2007, 09:24 AM

To 84 FXRP

Has the vibration gotten progressively worse? Or was there a sudden on set of vibration at 2800/3000 rpm?
ANSWER: THE VIB JUST STARTED LIKE ALL AT ONCE
84FXRP: Indicates that it isn't something that just wore out.

Is the vibration associated with a particular speed or with a particular rpm?
That is do you have the same vibration at 2800/3000 rpm in 4th gear as you do at 2800/3000 rpm in 5th gear? Or do you notice the vibration at 50 to 60 mph regardless to the gear you are in? Does the vibration abate when you pull in the clutch?
ANSWER: THE VIB IS MUCH STRONGER AT 55 MPH IN 5TH GEAR
YES WHEN I PUT IN THE CLUTCH THE VIB STOPS
84FXRP: Indicates that it isn't wheels or tires.

New Question ----> 84FXRP: Have you inspected the slack on the primary chain?

Have you checked the tightness of all the engine mount fasteners?
ANSWER: THE FRONT IS NEW/RUBBER MOUNT THE REAR DONT KNOW
84FXRP: You might check the fasteners on the engine mount and engine to transmission anyway. It is possible that a bolt has loosened. The top motor mount is under the tank.

Does the bike track straight?
ANSWER: YES
84FXRP: Indicates it is not an alignment problem.

Do you have spoked or cast wheels? Any loose spokes? Any damage to the wheel?
ANSWER: FRONT SPOKE REAR CAST
84FXRP: Given your earlier response it does not seem like it is a wheel.

Lost any wheel balance weights?
ANSWER: NO
84 FXRP: Check

Where do you notice the vibration? (handlebars, seat, foot peg, etc)
ANSWER: FOOT PEGS AND HANDLEBARS THE SEAT I DONT NOTICE
84FXRP: Check

Are all the exhaust pipes properly aligned with the fasteners tightened? Any interference with the exhaust system and the frame of the bike?
ANSWER: THE EXHAUST IS IN FINE SHAPE ALL ALINGNED AND TIGHT NO INTERFERANCE.
84FXRP: Check

ONE LAST BIT OF INFO THE VIBRATION STARTED ABOUT THE SAME TIME MY TRANNY WAS OVER FULLED
TO THE POINT THAT LUBE WAS COMING OUT THE SPLIT HALF. ALL LUBE WAS DRAINED AND FILLED
TO THE PROPER LEVEL. DONT KNOW HOW THAT COULD CAUSE THE PROBLEM.

It is interesting that the vibration is associated with 5th gear at 2800/3000 rpm but not 4th gear and the same rpm, and the initial onset with the tranny overfill. The 5th gear, but not 4th gear, aspect of the problem would seem to point towards the transmission. Although, I agree with you, that it is difficult to see how that would have caused the problem.

Can you duplicate the vibration at ANY engine speed in 4th gear?

Sorry, not much help.

Bluesman · 09-13-2007, 10:00 AM

New Question ----> 84FXRP: Have you inspected the slack on the primary chain?
Answer: The slack is to spec but I don't know how much it is worm
I do believe the vib is getting worse (hard to tell) when the vib
starts at 50 mph one can here just a slight bumble or howl
it is hard to tell with the wind but I can here a change in the sound of the
bike
Looking at things...if it was a bearing or shaft the vib would be there all times
and for sure as the rpm/speed goes up but that is not the case.
It must be some type of harmonic that becomes active at the 2600/2800 rpm
right? I have check everything that I can think of outside of the bike

Bluesman · 09-13-2007, 10:57 AM

OK new info
#1 the vib is in every gear
#2 the lower gears do not have as much vib
because one goes through the vib rpm fast
#3 5th gear has the most vib
#4 The vib is strongest in 5th gear with a load
#5 The vib starts at 2500 and is gone at 3000 and on up

We have a 30 mph wind with gust to 45 up here today so it is a little
hard to pick up any noise.

Again the vib seams to be in the front more then the back
The foot pegs handlebars and also the fuel tank vib.
so it could be the engine rear mount ?

bigjailerman · 09-13-2007, 12:25 PM

Hey 84 - Could the frame be cracked somewhere and getting worse??

84FXRP · 09-13-2007, 02:35 PM

Quote:

Originally Posted by Bluesman

...Again the vib seams to be in the front more then the back
The foot pegs handlebars and also the fuel tank vib.
so it could be the engine rear mount ?

The rear vibration isolation system is the rubber cleve blocks in the swing arm pivot. These are pretty tough. The bike would seem "squirrelly" in the corners if they were failing.

If the bike always had the vibration issue I would suggest tweeking the top motor mount stabilizer. But given the sudden on set of the vibration issue I don't think that would be the problem.

Sorry I have not been much help, vibration issues are sometimes difficult to isolate.

----------

(FYI - If an FXR tracks straight (properly aligned) and has excessive vibration, ONE POSSIBLE reason is stress on the top motor mount. With the FXR blocked upright - (vertical - NOT resting on it's jiffy stand) remove the fuel tank.

There is a turn-buckle that attaches the top motor mount to the frame. One bolt thru the turnbuckle attaches it to the frame. The other bolt thru the turnbuckle attaches it to the motor mount on the top of the engine.

Loosen and remove the bolt attaching the turnbuckle to the top motor mount. With the motorcycle blocked vertical, start and run the engine for 10-15 seconds.

Stop the engine.

Now, with the motorcycle upright (vertical), the removed bolt (bolt that attaches the turnbuckle to the top engine mount) should just DROP through the turnbuckle and into position on the engine mount. DON'T HAVE ANY SIDE TO SIDE PRESSURE ON THE ENGINE TO GET THE BOLT TO ALIGN.

If the bolt doesn't just "drop" into position, then (keeping the bike vertical) adjust the turn buckle until the bolt just falls into place. Torque fasteners to spec and replace the gas tank.

Sometimes folks don't follow the Service Manual and replace the front motor mount or try to align the bike without removing the top motor mount turnbuckle bolt.

84FXRP · 09-13-2007, 02:40 PM

Quote:

Originally Posted by bigjailerman

Hey 84 - Could the frame be cracked somewhere and getting worse??

Possible, but Bluesman didn't indicate that the bike rode "funny" in corners. Also he didn't mention any event that might have damaged the frame. FXR frames are pretty substantial but you can always break something.

Bluesman · 09-14-2007, 10:14 AM

To 84FXRP:
Well it looks like you were right about the upper engine mount and turnbuckle.
The turnbuckle bolt to the engine is so tight I can not get it out.
There has to be a great deal of side pressure on the bolt because I gave it a good whack
a few times and it did not move. There is not much room to try to remove it so
I guess the best thing is to take it to the service center for the repair.

I am sure that the problem is when the lower motor mount was replaced they did
not adjust the upper turnbuckle.

harley92 · 09-14-2007, 10:22 PM

just a dumb question does it have the b engine if so you should ck the ballance shaft chains and tentioners

Bluesman · 09-15-2007, 12:12 PM

84 FXRP:
Well got the bolt out and the turnbuckle was off 1/4 inch I just came
back from a test ride and 75% of the vibration is gone.
I still have the vib at the 2000 rpm like it was from day one but the
50-60 mph has improved.
I am betting that the lower turnbuckle need to be adjusted as well.

Where did you get the info that you posted ? and does the same
procedure apply for the lower turnbuckle ?

84FXRP · 09-15-2007, 05:30 PM

Quote:

Originally Posted by Bluesman

84 FXRP:
Well got the bolt out and the turnbuckle was off 1/4 inch I just came
back from a test ride and 75% of the vibration is gone.
I still have the vib at the 2000 rpm like it was from day one but the
50-60 mph has improved.
I am betting that the lower turnbuckle need to be adjusted as well.

Where did you get the info that you posted ? and does the same
procedure apply for the lower turnbuckle ?

DON'T MESS WITH THE LOWER TURNBUCKLE IF THE BIKE TRACKS OK!

The lower turnbuckle is used to align the bike. If the bike's alignment is ok DON'T adjust the turnbuckle.

The rubber "donut" on the front motor mount should have equal "squish" all around. The Shop Manual has a procedure for changing/adjusting the centering of the rubber donut.

Problem is that one thing CAN effect another. You could loosen the bolt that runs through the motor mount, lift the engine JUST enough to allow you to center the rubber mount, then retorque the bolt down. This MIGHT cause the alignment to be off.

BTW the alignment is easy to check using a couple of straight edges. I liked to use long florescent lamp tubes.

What got you into this situation is that the mechanic did not remove the top motor mount bolt when the bike was aligned. The Shop Manual requires this bolt be removed while the alignment is obtained, but removing the bolt requires removing the gas tank. The mechanic saved time by not following all the procedures, but the result is a bike that vibrates.

The Shop Manual does not call for idling the engine 15-30 seconds, but this extra step allows the motor to "center itself" as good as it can be. A HD mechanic showed me this procedure in the days LONG before Harleys were popular. LOL

I would check to see if the motor mount rubber isolator seems "centered" in the mount. If it is squished out to one side, then correction is in order. Before you do this be sure to have access to a real HD Service Manual - the manual makes this pretty straight forward.

Bluesman · 09-16-2007, 05:08 PM

Thanks for all the help I think the vib is fixed and what is left would be normal

Bluesman · 10-02-2007, 10:36 AM

84FXRP:
This is a follow up to my Vibe problem. As stated above after adjusting the top stabilizer
most of the vibration went away. So with things seeming to be normal I took of
on a early fall ride of 500 miles. After about 175 miles into the ride the vibration came back
with a vibe from Hell. I canceled the rest of the trip and rode back keeping the
bike in the 70/75 mph range (smoothes out at that speed)

After think about all the things that have been replaced it came to me (with a bang)
that just maybe the stabilized rubber bushing had gone hard .
I check all my records and figured out they had not been replaced
"Never" So I have 2 new stabilizers on order and I believe that may be the problem
because I tried to punch a screwdriver in the side of one and it was like iron.

My question to you is what about rear mounts ? Why nothing is said that the problem
would be there ? As I see it the top mount is just a horizontal stabilizer right ?

What do you think ?