vibration at higher rpm - Victory Forums - Victory Motorcycle Forum
 6Likes
Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 20 (permalink) Old 10-06-2018, 02:38 PM Thread Starter
Member
 
Gkyle840's Avatar
 
Join Date: Oct 2018
Location: Columbus ohio
Posts: 30
Default vibration at higher rpm

I purchased a 2004 vegas this month and love it so far but it has a pretty good vibration to it. as far as I know, the bike is stock. starting around 2500 rpm there is a pretty good vibration that gets worse as the rpm increase. I have ran it around 4000 rpm and pulled the clutch in and the vibration immediately goes away. normally I would set the valve clearance and rebuild and sync the carbs but ive never had a fuel injected bike so im not sure where to start.
Gkyle840 is offline  
Sponsored Links
Advertisement
 
post #2 of 20 (permalink) Old 10-06-2018, 03:19 PM
Senior Member
 
adamnorthup's Avatar
 
Join Date: May 2016
Location: Boise ID
Posts: 277
Garage
Default

Quote:
Originally Posted by Gkyle840 View Post
I purchased a 2004 vegas this month and love it so far but it has a pretty good vibration to it. as far as I know, the bike is stock. starting around 2500 rpm there is a pretty good vibration that gets worse as the rpm increase. I have ran it around 4000 rpm and pulled the clutch in and the vibration immediately goes away. normally I would set the valve clearance and rebuild and sync the carbs but ive never had a fuel injected bike so im not sure where to start.
If you have it at 4k with the clutch in what does it do? 4000rpm while in neutral on kickstand, vs Pull in clutch at 60 with engine idle tells a good story. Might sound dumb but don't ignore belt tension either. Too tight will do weird stuff - squeaks, vibes, etc, and will change on/off throttle..

XC, KP, & Custom MuscleVic in Boise
adamnorthup is offline  
post #3 of 20 (permalink) Old 10-06-2018, 03:57 PM Thread Starter
Member
 
Gkyle840's Avatar
 
Join Date: Oct 2018
Location: Columbus ohio
Posts: 30
Default

while cruising at 4000 rpm and then pulling in the clutch and having the vibration stop tells me its not a tire or alignment/suspension issue which I originally thought was the case. when I cruise at 4000rpm it vibrates pretty badly and when I pull the clutch in and the rpm drop the vibration smooths out. I have tried it in 2nd, 3rd and 4th gear at different rpms and the result is the same for each gear.

as for the belt tension, I have never owned a belt driven motorcycle but was told compared to most makes, victory wants their belts looser than most makes. I have a belt tension gauge and did set the tension and align the rear wheel as per the manual at 10 lbs pressure but it didnt seem particularly loose to me and I double checked it on the stand after everything was tightened.
visionjohnny and adamnorthup like this.

- 2004 Vegas Arlen Ness that is all stock.
Gkyle840 is offline  
Sponsored Links
Advertisement
 
post #4 of 20 (permalink) Old 10-06-2018, 04:57 PM
Senior Member
 
adamnorthup's Avatar
 
Join Date: May 2016
Location: Boise ID
Posts: 277
Garage
Default

Quote:
Originally Posted by Gkyle840 View Post
while cruising at 4000 rpm and then pulling in the clutch and having the vibration stop tells me its not a tire or alignment/suspension issue which I originally thought was the case. when I cruise at 4000rpm it vibrates pretty badly and when I pull the clutch in and the rpm drop the vibration smooths out. I have tried it in 2nd, 3rd and 4th gear at different rpms and the result is the same for each gear.

as for the belt tension, I have never owned a belt driven motorcycle but was told compared to most makes, victory wants their belts looser than most makes. I have a belt tension gauge and did set the tension and align the rear wheel as per the manual at 10 lbs pressure but it didnt seem particularly loose to me and I double checked it on the stand after everything was tightened.
Yep - that's what I was asking. Fresh plugs are cheap & you should do a compression check while you swap them. If compression isn't balanced between the cylinders, save the new plugs for when you get it fixed. Sounds like you have a dead or weak cylinder maybe? Tough to tell remotely!

XC, KP, & Custom MuscleVic in Boise
adamnorthup is offline  
post #5 of 20 (permalink) Old 10-06-2018, 05:08 PM Thread Starter
Member
 
Gkyle840's Avatar
 
Join Date: Oct 2018
Location: Columbus ohio
Posts: 30
Default

I did put new plugs in it and change the oil when I got it home. I will check the compression and see if the cylinders are close to each other but thats about all the harbor freight kit is good for.

as for the belt, should it feel somewhat tight? just want to make sure my belt adjustment was done properly because it is drastically tighter than it was initially on the bike when I bought it. it had a ton of play initially.

- 2004 Vegas Arlen Ness that is all stock.
Gkyle840 is offline  
post #6 of 20 (permalink) Old 10-06-2018, 05:47 PM
Senior Member
 
adamnorthup's Avatar
 
Join Date: May 2016
Location: Boise ID
Posts: 277
Garage
Default

Get someone to help roll it until you find the tightest spot - can make a difference. Manual says 10lbs pressure should move belt by 11mm (7/16") from relaxed position using the belt tension gauge.
If you don't have the tension meter, as a sanity-check you can grab the belt with a couple fingers, it should have over half-inch from pushing down to lifting up.
10 lbs isn't much pressure.
If up/down is under an inch when I change oil, I don't bother checking with the meter (slacker).
Tight is worse than loose, IMO. Tight can give squeaks/creaks, a low frequency hum, and wear out bearings and sprockets quicker.

Compression should be 180 +20. Meaning 200 is fine, but under 180 is bad. If that's the source of vibration, you'd have significant disparity between the cylinders.

A fuel issue with one or the other cylinder can cause similar issue to a low compression cylinder. Tougher to see, but same basic symptom - one cylinder not firing well. Doesn't hurt to throw an ounce per gallon of seafoam in the gas. That does a better job cleaning up fuel resins than any injector cleaner I've used, even though it sounds a little redneck.

Another way to tell if a cylinder isn't firing well is to use a laser thermometer & check the temp of the headpipes. If one is significantly lower than the other (use high-idle choke lever to spin it up a little) then ignition, fuel, or compression is bad in the low cylinder. Prob the quickest way to isolate to engine?
Quote:
Originally Posted by Gkyle840 View Post
I did put new plugs in it and change the oil when I got it home. I will check the compression and see if the cylinders are close to each other but thats about all the harbor freight kit is good for.

as for the belt, should it feel somewhat tight? just want to make sure my belt adjustment was done properly because it is drastically tighter than it was initially on the bike when I bought it. it had a ton of play initially.
XC, KP, & Custom MuscleVic in Boise
adamnorthup is offline  
post #7 of 20 (permalink) Old 10-06-2018, 06:00 PM Thread Starter
Member
 
Gkyle840's Avatar
 
Join Date: Oct 2018
Location: Columbus ohio
Posts: 30
Default

thanks! one discrepancy with the belt. the manual that I downloaded stated the tension should be set at 9mm at 10lbs of force.
it says it is the service manual for 2003-2005 vegas and kingpins.

I will check the compression, temps and throw some seafoam in the tank which I have plenty of, lol.

- 2004 Vegas Arlen Ness that is all stock.
Gkyle840 is offline  
post #8 of 20 (permalink) Old 10-06-2018, 06:04 PM Thread Starter
Member
 
Gkyle840's Avatar
 
Join Date: Oct 2018
Location: Columbus ohio
Posts: 30
Default

This is the service manual that I downloaded.
Attached Images
File Type: jpg Screenshot_20181006-185627_Adobe Acrobat_1538867037912.jpg (22.7 KB, 2 views)

- 2004 Vegas Arlen Ness that is all stock.
Gkyle840 is offline  
post #9 of 20 (permalink) Old 10-06-2018, 09:04 PM
Senior Member
 
RICZ's Avatar
 
Join Date: Sep 2010
Location: Portland,Oregon
Posts: 12,061
Default

I gotta dive in here to set this belt voodoo straight. I set mine by the manual and it would be guitar string tight when hot. When it's hot is the crucial test. I even rechecked, adjusting per the manual instructions, and yes, I have the belt tension gauge. A tight belt has to be hard on bearings.
I was talking about this with an Aussie who frequents this forum. He is a prolific hotrodder and engine builder and drag races his bikes and cars. His advice was to adjust the belt so that there is some slack in it what it gets hot. I took his advice and all is good and the gauge is collecting dust.
visionjohnny and adamnorthup like this.

2010 Midnight Cherry XR. 7Jurock, Lloydz AF, ATS, AFR tuned VFCIII, IAV, and T-6 and locally repacked pipes = big smiles. SOLD to a dear friend, so it's still in the family."
2017 Spyder F3 Limited - keeps this old guy in the wind and riding with friends.
Cure that ugly stand up license plate with the cheapest and best laydown bracket. Click this:
https://www.victoryforums.com/11-ven...t-x-bikes.html
RICZ is online now  
post #10 of 20 (permalink) Old 10-06-2018, 10:52 PM
Senior Member
 
adamnorthup's Avatar
 
Join Date: May 2016
Location: Boise ID
Posts: 277
Garage
Default

Quote:
Originally Posted by Gkyle840 View Post
This is the service manual that I downloaded.
Mine is an 06 manual. Says 11mm for 03-05 & 12mm for 06. Maybe they learned to loosen it a bit? I'll check my 2012 manual & see what it says!

I leave mine on my bikes on the loose side & works well & quietly.

XC, KP, & Custom MuscleVic in Boise
RICZ likes this.
adamnorthup is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Victory Forums - Victory Motorcycle Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome