Author Topic: V85 beware  (Read 5623 times)

Offline rudyr

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V85 beware
« on: September 19, 2021, 04:33:58 PM »
Last week going to Cedar vale, at stop lite I did a shot gun start got the front wheel off the ground about a foot, ( loaded with camping gear about 120lb. Plus me175lb.) haven’t adjusted the shock off low poison because of my 8’9” height.  Well today coming back from mo-can passing a car faster than I like, started getting a high speed wable.  Pull back on the bars nothing( pushing against my back pack gear , so let off the gas that’s when it got really bad bad. How do you get out of a high speed wobble more power and more power pushing on the bars as hard as I could, got out of it but I was going really fast(I don’t think I changed lanes but all those car’s were about 1/4 mile behind now and not ant hurry to come any closer. What I think running over loaded with out spring tension on shock. You guy’s beware.It was bad I don’t think I went stop to stop but I have when I was 50 year’s younger.Rudy

Offline Kiwi Dave

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Re: V85 beware
« Reply #1 on: September 19, 2021, 04:58:11 PM »
I'd say it was because of the way you loaded your bike.  Were you using proper pannier bag arrangement, or was the load piled high on the seat behind you?

I've never had any issue with my V85.

I guess the other reason might be your 8' 9" in height!

Online tommy2cyl

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Re: V85 beware
« Reply #2 on: September 19, 2021, 05:14:49 PM »
120 lbs of camping gear?  I carry 2 person tent, cot, air mattress, sleeping bag, folding chair, clothing, food, Jet Boil, tools and necessary miscellaneous and I top out around 65 lbs.  I ditched the aluminum panniers and rear case and use Nelson Rigg soft luggage panniers and Moose Racing 40 liter tail bag.  Switching to soft luggage saves about 28 lbs.  You must carry a lot of gear and if it truly is 120 lbs, your rear end heavy front end light.

Offline lucian

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Re: V85 beware
« Reply #3 on: September 19, 2021, 05:34:01 PM »
Is the gear on a rear rack or strapped to the pillion seat? 120 lbs. on a rear rack would explain the wheelie and the wobble. 120 lbs on the pillion seat should not be a problem.  How's your tire pressures and wear?  Glad you pulled out of it before things got really weird! 

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Re: V85 beware
« Reply #3 on: September 19, 2021, 05:34:01 PM »

Offline Huzo

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Re: V85 beware
« Reply #4 on: September 19, 2021, 06:01:29 PM »
I moved the top box 150mm forward on mine, but I doubt the issue is related to centre of mass.
If that was an issue, everyone who took a pillion would crash.
Tyre pressure ok ?
Rim straight ?
Road irregularity?

Offline HarveyMushman

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Re: V85 beware
« Reply #5 on: September 19, 2021, 06:03:42 PM »
Last week going to Cedar vale, at stop lite I did a shot gun start got the front wheel off the ground about a foot, ( loaded with camping gear about 120lb. Plus me175lb.) haven’t adjusted the shock off low poison because of my 8’9” height.  Well today coming back from mo-can passing a car faster than I like, started getting a high speed wable.  Pull back on the bars nothing( pushing against my back pack gear , so let off the gas that’s when it got really bad bad. How do you get out of a high speed wobble more power and more power pushing on the bars as hard as I could, got out of it but I was going really fast(I don’t think I changed lanes but all those car’s were about 1/4 mile behind now and not ant hurry to come any closer. What I think running over loaded with out spring tension on shock. You guy’s beware.It was bad I don’t think I went stop to stop but I have when I was 50 year’s younger.Rudy

I don't think a warning to others is necessary. You, on the other hand, could learn a thing or two about suspension set up.  One lesson would be that the preload setting is not for adjusting ride height.  If you were carrying that much weight and with little to no preload applied to the rear shocks you caused this problem.   
Tim

Offline lucian

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Re: V85 beware
« Reply #6 on: September 19, 2021, 06:17:21 PM »
I would just add that a load aft relative to the rear axle center is relative to the overall stability at speed.  Add the wind load at high speed as well as a soft rear spring , things up front can get squirrely pretty quickly.

Offline Bulldog9

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Re: V85 beware
« Reply #7 on: September 19, 2021, 06:23:06 PM »
Too much speed, heavy load in the bags and not enough preload will almost always produce what you experienced.  Keep in mind that increasing the preload MAY increase ride height unladen, but with 120lbs of load plus your weight the bike will settle.

I haven't had much experience recently with a tank slapper or heavy front weave, but when I have had it, I was taught to stay on throttle loose arms on the bars and shift weight forward and down, basically laying over tank.
« Last Edit: September 19, 2021, 06:32:45 PM by Bulldog9 »
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Re: V85 beware
« Reply #8 on: September 19, 2021, 06:33:33 PM »
I dunno... I regularly carry 120-ish lbs of camping gear.  Its called my wife.  She is the ultimate camping gear.  And I think I'm the only guy she's ever done anything with that WASN'T around 8' 9"...
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Re: V85 beware
« Reply #9 on: September 19, 2021, 06:42:25 PM »
I don't think a warning to others is necessary. You, on the other hand, could learn a thing or two about suspension set up.  One lesson would be that the preload setting is not for adjusting ride height.  If you were carrying that much weight and with little to no preload applied to the rear shocks you caused this problem.   




I think he figured that out. That is some scary shit. BTDT
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Offline Huzo

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Re: V85 beware
« Reply #10 on: September 19, 2021, 06:59:58 PM »
You, on the other hand, could learn a thing or two about suspension set up.  One lesson would be that the preload setting is not for adjusting ride height. 
Oh ok then.
So in your own words, if pre load is not used to adjust ride height by reducing static sag, what is it’s function ?
Please stay on point... :popcorn:

Offline Huzo

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Re: V85 beware
« Reply #11 on: September 19, 2021, 07:16:06 PM »
Too much speed, heavy load in the bags and not enough preload will almost always produce what you experienced.  Keep in mind that increasing the preload MAY increase ride height unladen, but with 120lbs of load plus your weight the bike will settle.
Yes the bike will settle, but the alteration of pre load will NOT alter the LENGTH that the spring settles TO.
It will only reduce the static sag.
If your unpreloaded spring is 200 mm long when FULLY LADEN, it will still be 200 mm long FULLY LADEN, when you add preload.
So you see that the SPRING is in the same condition compression wise, but it has not allowed as much static sag, so therefore the damping rod is not as compressed, therefore the ride height is higher.

Just consider this...
You have loaded your bike ready to go with rider aboard and a glamorous assistant holds it level on it’s wheels.
The damper rod is compressed 100 mm, so it’s 100 mm away from it’s top stop, it is NOT topped out.
You then have someone wind on 50 mm of pre load while you are on board.
As the bottom adjuster is being wound up, what stops the top collar retreating away from the compressing spring ?
NOTHING...!
After you have added 50 mm of pre load (and the spring is holding the same weight as before), the compressed length of the spring will be the same as before you added the pre load, it’ll just result in the damper rod being 50 mm more extended, giving increased ride height but not an alteration to the performance of the spring.

Please if you’re going to respond, don’t tell me “My mate used to have a Norton.........and. ..Ummm....”
« Last Edit: September 23, 2021, 04:08:02 PM by Huzo »

Offline lucian

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Re: V85 beware
« Reply #12 on: September 19, 2021, 07:17:21 PM »
Optimal pre load is only as good as a  given spring rating. Ride height means little if you have to  exceed  the optimal range of a spring to achieve a given ride height.

Offline Huzo

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Re: V85 beware
« Reply #13 on: September 19, 2021, 07:23:16 PM »
Optimal pre load is only as good as a  given spring rating. Ride height means little if you have to  exceed  the optimal range of a spring to achieve a given ride height.
Do you not agree Lucian, that the spring “range” (rating would be better), is independent of pre load.
The spring does not know what ride height you have.
If you stand on the 3rd rung of a ladder and use a slinky, you can stand on the 5th rung and the slinky will perform the same, it’s just further up the ladder..... :grin:
« Last Edit: September 19, 2021, 07:37:17 PM by Huzo »

Offline Huzo

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Re: V85 beware
« Reply #14 on: September 19, 2021, 07:34:51 PM »
Probably a combination of things caused this .
 TS
I’d say that’s somewhat certain mate.
« Last Edit: September 19, 2021, 07:37:41 PM by Huzo »

Offline rudyr

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Re: V85 beware
« Reply #15 on: September 19, 2021, 07:47:31 PM »
My top case is Give 30 L about 10 lb. of cargo.  Tire pressure though came after the wild ride plus stem torque plus high front fender, 8500 miles on bike And by pushing hard forward I did put weight on the front.  TheGive planners had about 20 lbs. evenly. I pack wide and tight not over the top of the case except my coat. I my have been going fast when I got control and started slowing down I was at 92 mph I don’t know how fast I had to go to get out of the warble it didn’t go away easily. I think when I pasted the car I my have doing 90 + mph I wasn’t looking and then when it started I didn’t look had to much on my mind. Speed ca kill.Rudy

Offline Moto Vita

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Re: V85 beware
« Reply #16 on: September 19, 2021, 08:05:14 PM »
My top case is Give 30 L about 10 lb. of cargo.  Tire pressure though came after the wild ride plus stem torque plus high front fender, 8500 miles on bike And by pushing hard forward I did put weight on the front.  TheGive planners had about 20 lbs. evenly. I pack wide and tight not over the top of the case except my coat. I my have been going fast when I got control and started slowing down I was at 92 mph I don’t know how fast I had to go to get out of the warble it didn’t go away easily. I think when I pasted the car I my have doing 90 + mph I wasn’t looking and then when it started I didn’t look had to much on my mind. Speed ca kill.Rudy

 Well that clears things up.

Offline Huzo

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Re: V85 beware
« Reply #17 on: September 19, 2021, 08:07:05 PM »
My top case is Give 30 L about 10 lb. of cargo.  Tire pressure though came after the wild ride plus stem torque plus high front fender, 8500 miles on bike And by pushing hard forward I did put weight on the front.  TheGive planners had about 20 lbs. evenly. I pack wide and tight not over the top of the case except my coat. I my have been going fast when I got control and started slowing down I was at 92 mph I don’t know how fast I had to go to get out of the warble it didn’t go away easily. I think when I pasted the car I my have doing 90 + mph I wasn’t looking and then when it started I didn’t look had to much on my mind. Speed ca kill.Rudy
Yep, I reckon I got most of that.
Your bike should not be so close to disaster that such a thing could cause trouble. With a pillion and no luggage, your centre of mass would still be further back than your situation.
Check..
Headstem bearings Adjust/grease or replace.
Handlebar attachment bolts.
Every fastener that holds the forks in.
Wheel bearings.
Axle pinch bolts.
Front wheel true
Front wheel balance...(not the same thing)
Front tyre condition.
Front tyre pressure.

Offline lucian

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Re: V85 beware
« Reply #18 on: September 19, 2021, 08:26:10 PM »
Do you not agree Lucian, that the spring “range” (rating would be better), is independent of pre load.
The spring does not know what ride height you have.
If you stand on the 3rd rung of a ladder and use a slinky, you can stand on the 5th rung and the slinky will perform the same, it’s just further up the ladder..... :grin:
I don't understand the slinky analogy, From rung to rung the slinky would perform the same , but dropped to the floor off rung three vs. rung five the Slinky's spring rate would diminish greatly , It's important to consider static sag and spring rate relative to rider sag when determining preload. Ride height is only relevant when the spring rate and rider sag are within the acceptable range.
« Last Edit: September 19, 2021, 08:44:01 PM by lucian »

Offline Bulldog9

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Re: V85 beware
« Reply #19 on: September 19, 2021, 09:00:00 PM »
Yes the bike will settle, but the alteration of pre load will NOT alter the LENGTH that the spring settles TO.
It will only reduce the static sag.
If your unpreloaded spring is 200 mm long when FULLY LADEN, it will still be 200 mm long FULLY LADEN, when you add preload.
So you see that the SPRING is in the same condition compression wise, but it has not allowed as much static sag, so therefore the damping rod is not as compressed, therefore the ride height is higher.

Just consider this...
You have loaded your bike ready to go with rider aboard and a glamorous assistant holds it level on it’s wheels.
The damper rod is compressed 100 mm, so it’s 100 mm away from it’s top stop, it is NOT topped out.
You then have someone wind on 50 mm of pre load while you are on board.
As the bottom adjuster is being wound up, what stops the top collar retreating away from the compressing spring ?
NOTHING...!
After you have added 50 mm of pre load (and the spring is holding the same weight as before), the compressed length of the spring will be the same as before you added the pre load, it’ll just be 50 mm more extended, giving increased ride height but not an alteration to the performance of the spring.

Please if you’re going to respond, don’t tell me “My mate used to have a Norton.........and. ..Ummm....”

Youre talking in circles my friend ;-)

Cranking up the preload will result in an increase of static (unladen) ride height, and reduce sag. Never mentioned or implied increasing spring length. It is all about resistance to load and resulting height. My point was he said he had the preload on lowest setting to keep the static height lower due to his 8'9" height. I'm assuming he meant 5'9" All I was pointing out was that his increased load would have likely brought the ride height down to where it was on the lowest setting unladen, and remove his concern about reaching.
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Offline Huzo

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Re: V85 beware
« Reply #20 on: September 19, 2021, 09:09:37 PM »
I don't understand the slinky analogy, From rung to rung the slinky would perform the same , but dropped to the floor off rung three vs. rung five the Slinky's spring rate would diminish greatly , It's important to consider static sag and spring rate relative to rider sag when determining preload. Ride height is only relevant when the spring rate and rider sag are within the acceptable range.
The spring RATE would not alter however high you drop it from. The RATE is the amount the spring deflects (squashes), under a GIVEN load...(Check the definition).
Your example is varying the load by dropping it from higher.
My tongue in cheek analogy was for two reasons, one is to demonstrate that the spring does not have a different RATE if it is operating at a different part of the shock’s limits, that is in between zero and full pre load.
The RATE is a function of wire diameter, number of turns (angle) and if everyone has their say, spring material.
The spring in Rudy’s bike has the same wire diameter and number of turns no matter how it is pre loaded.
The other reason I tried to introduce some levity, was to hopefully stop a fight breaking out...(again).

It’s usually best to imagine the shock out on the bench with a load to compress it and imagine (or measure), the state of the spring before and after you root around with the pre load. If all else fails, ask Isaac Newton.

Offline rudyr

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Re: V85 beware
« Reply #21 on: September 19, 2021, 09:13:10 PM »
Fat finger my height 5’9”.  I’m not basket ball player. My speed limit in this state on free ways 75 mph.  I normally run about 3 mph over.  Now passing can be something else. I have painted as clear a picture of what happened today.  I’m thinking I took the bike pasted it’s limit for the shock set up.  This week end I did look at a v85 with a 1” shorter mono shock and front tubes moved up 3/4” they said it worked good.  I do have very small Give tank bag, coup of maps and gloves.Rudy

Offline Huzo

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Re: V85 beware
« Reply #22 on: September 19, 2021, 09:15:22 PM »
Youre talking in circles my friend ;-)

Cranking up the preload will result in an increase of static (unladen) ride height, and reduce sag. Never mentioned or implied increasing spring length. It is all about resistance to load and resulting height. My point was he said he had the preload on lowest setting to keep the static height lower due to his 8'9" height. I'm assuming he meant 5'9" All I was pointing out was that his increased load would have likely brought the ride height down to where it was on the lowest setting unladen, and remove his concern about reaching.
If you’ll agree that altering pre load will not change the ride quality, then we are on the same page.
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Offline Huzo

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Re: V85 beware
« Reply #23 on: September 19, 2021, 09:21:36 PM »
Youre talking in circles my friend ;-)

Cranking up the preload will result in an increase of static (unladen) ride height, and reduce sag. Never mentioned or implied increasing spring length. It is all about resistance to load
Yes and there is no real argument there, the bike will settle less when you roll it off the centrestand and the weight of the unladen bike hits the wheels, but the spring will be in the same condition (length) after you jump on, as it would have been if you’d added no pre load.
It’s just that the eye to eye length of the shock is greater (longer) so ride height is increased.
« Last Edit: September 19, 2021, 09:29:55 PM by Huzo »

Offline wymple

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Re: V85 beware
« Reply #24 on: September 19, 2021, 09:23:00 PM »
You beat the dreaded front end wobble by loading the front wheel, not by trying to get away from it. Get your weight up on those bars.
No trees were harmed by the conveyance of this message, but a lot of electrons were seriously disturbed.

Offline Bulldog9

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Re: V85 beware
« Reply #25 on: September 19, 2021, 09:52:53 PM »
Yes and there is no real argument there, the bike will settle less when you roll it off the centrestand and the weight of the unladen bike hits the wheels, but the spring will be in the same condition (length) after you jump on, as it would have been if you’d added no pre load.
It’s just that the eye to eye length of the shock is greater (longer) so ride height is increased.

Yup, on the same page.  :bow:
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Offline Huzo

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Re: V85 beware
« Reply #26 on: September 19, 2021, 10:48:25 PM »
Yup, on the same page.  :bow:
Good stuff.. :thumb:

Offline lucian

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Re: V85 beware
« Reply #27 on: September 20, 2021, 06:12:18 AM »
"Your example is varying the load by dropping it from higher."

Exactly!    Just as loading the rear and not increasing  the preload. Adding preload in the slinky example would amount to lowering the rung as the slinky works in tension not compression as a rear shock.
 

Offline mechanicsavant

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Re: V85 beware
« Reply #28 on: September 20, 2021, 07:58:53 AM »
120 lbs. of kit , wow I thought I carried everything but the kitchen sink . I’ve scaled my load @ 80 lbs. or so . Did ya get the cast iron camping sink? Just kidding I’m glad to hear it ended well & may educate others

Offline Luap McKeever

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Re: V85 beware
« Reply #29 on: September 20, 2021, 08:39:59 AM »
So would it do it with a 120 lb passenger? In my mind your load isn't the issue if properly balanced. I'd for sure do some checking if it were me. Doesn't sound right. But it could have been an anomaly too like a wind gust, road imperfection, etc if it was a singular issue.

+1 on Huzo's comment.
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