ADVrider

Go Back   ADVrider > Bikes > Hacks
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 06-10-2015, 06:04 PM   #1
jeffjbmw OP
Threadkiller
 
jeffjbmw's Avatar
 
Joined: Aug 2006
Location: Magdalena, NM
Oddometer: 893
Measuring downward force on hack wheel

Has anyone measured the downward force on the sidecar wheel (in real time) to get a sense of when it is about to "fly"?

I was thinking strain gauge and display....
__________________
You can never have too many motorcycles and musical instruments. But if it is only one of each....... a R1200GS. And a Martin 00-18H......

Read my blog: http://jeffszen.blogspot.com/
jeffjbmw is online now   Reply With Quote
Old 06-10-2015, 06:32 PM   #2
usgser
Beastly Adventurer
 
Joined: Nov 2005
Location: Westside WA
Oddometer: 2,314
Screw techno or cell apps as an easy by-pass for experience short cut. Study up on sidecar handling characteristics, then spend the seat time practicing learning. Unless you're a total idiot, you'll survive.
usgser is offline   Reply With Quote
Old 06-10-2015, 07:30 PM   #3
pagomichaelh
Gnarly Adventurer
 
Joined: Nov 2013
Location: Tafuna, American Samoa
Oddometer: 108
Quote:
Originally Posted by jeffjbmw View Post
Has anyone measured the downward force on the sidecar wheel (in real time) to get a sense of when it is about to "fly"?

I was thinking strain gauge and display....
One of the Hal Kendall books has the maths shown.

I threw some thoughts this direction, using an accelerometer, inclinometer, and a PIC controller, with a buzzer and light/flasher for output before we picked up our rig.

With seat time, what I finally decided is what is happening isn't really all that important (read - too late), it's what's GOING to happen is what you need to react to now (ie; a tightening turn), which would require a GPS/map interface to calculate the anticipated forces.

I could do the first in my spare time, I don't have enough spare time to do the second. Since the first would be just a 'gee whiz, look what I can do', I'd rather spend that time riding.
pagomichaelh is offline   Reply With Quote
Old 06-10-2015, 10:12 PM   #4
Boxer Metal
Mad Scientist
 
Boxer Metal's Avatar
 
Joined: Nov 2003
Location: Chico, California
Oddometer: 3,569
Twist that thing on the right side of the handlebar and push hard on the left side of the handlebar. You will have the answer right away
__________________
BOXER Metal
BMW Biker Scum
BMW Mad Scientist!
VBMWMO #7770, BMW MOA #48694 & Airhead BMW Club #600
Boxer Metal is offline   Reply With Quote
Old 06-11-2015, 03:49 AM   #5
Wolfgang55
Beastly Adventurer
 
Wolfgang55's Avatar
 
Joined: Dec 2006
Location: Next to Rio Bravo
Oddometer: 3,527
Sounds like a few want you to document your ''testing'' & then have your wife post up the results plus HER findings.

Much of what you ask is just experience & only one way to get that.
Noticed some of your roads would be the perfect test area(s).
Nearly void of on owing traffic, there should be a large percentage of success
Wolfgang55 is offline   Reply With Quote
Old 06-11-2015, 04:09 AM   #6
davebig
Another Angry Hun !
 
davebig's Avatar
 
Joined: Jan 2004
Location: Minnesota
Oddometer: 4,024
Quote:
Originally Posted by Boxer Metal View Post
Twist that thing on the right side of the handlebar and push hard on the left side of the handlebar. You will have the answer right away
Amen
Traditionally you go to a parking lot and do circles smaller and faster till you can predict the chair lifting, and remember that attitiude.
If your Dana you develop enough skill to do figure 8 s without setting the chair down.
__________________
Patience: A minor form of despair disguised as a virture.
Ambrose Bierce
davebig is online now   Reply With Quote
Old 06-11-2015, 06:16 AM   #7
Carl Childers
Ghost in the Machine
 
Carl Childers's Avatar
 
Joined: Dec 2012
Location: Northern New Mexico
Oddometer: 924
In this era of ABS and traction control and other computerized nanny devices is an anti-fly chair mode that far off?
__________________
New Mexico, not really new, not really Mexico.

Carl Childers screwed with this post 06-11-2015 at 06:22 AM
Carl Childers is online now   Reply With Quote
Old 06-11-2015, 06:39 AM   #8
leejosepho
Sure, I can do that!
 
leejosepho's Avatar
 
Joined: Jun 2011
Location: 200 miles north of New Orleans
Oddometer: 506
Quote:
Originally Posted by pagomichaelh View Post
...what is happening isn't really all that important (read - too late), it's what's GOING to happen...which would require a GPS/map interface to calculate the anticipated forces.
Quote:
Originally Posted by Carl Childers View Post
In this era of ABS and traction control and other computerized nanny devices is an anti-fly chair mode that far off?
Enough money could get the system produced, of course, but then who is ever going to convince the pilots we really do need to just relax at any given moment and let the system have control of the bars, throttle, brakes and such while we just continue along for the servo-controlled ride?!
__________________
He who so shall, so shall he who.
leejosepho is offline   Reply With Quote
Old 06-11-2015, 06:43 AM   #9
davebig
Another Angry Hun !
 
davebig's Avatar
 
Joined: Jan 2004
Location: Minnesota
Oddometer: 4,024
Quote:
Originally Posted by Carl Childers View Post
In this era of ABS and traction control and other computerized nanny devices is an anti-fly chair mode that far off?
Dog damn lets hope not about the time one's into a rt a little too quickly and the chair is bouncing and very lite one needs a sensor that depowers the rig so you can head on the 68 Peterbilt with 90k on in he oncoming lane !!!!!!!!!!!!!!!!!

I can still scare myself pretty decently without computer aid !!!!!!!!!!!!! My eventual demise will probably be a downhill off camber rt ! I often enter them way too fast and wish I hadn't but so far I've stayed on my side of the rd.DB
__________________
Patience: A minor form of despair disguised as a virture.
Ambrose Bierce
davebig is online now   Reply With Quote
Old 06-11-2015, 07:01 AM   #10
FR700
Heckler™©®
 
FR700's Avatar
 
Joined: May 2007
Oddometer: 8,458
Quote:
Originally Posted by davebig View Post
Dog damn lets hope not about the time one's into a rt a little too quickly and the chair is bouncing and very lite one needs a sensor that depowers the rig so you can head on the 68 Peterbilt with 90k on in he oncoming lane !!!!!!!!!!!!!!!!!

I can still scare myself pretty decently without computer aid !!!!!!!!!!!!! My eventual demise will probably be a downhill off camber rt ! I often enter them way too fast and wish I hadn't but so far I've stayed on my side of the rd.DB

If you had an independently controlled sidecar brake, in combination with a trailing arm suspension, you would merely need to lightly drag the sidecar brake in order to get the chair suspension to 'squat', thus transferring weight to the chair. The fact that it also works as a cutting brake should also not be overlooked. A kinda twofer deal, if you will.


.
__________________
I'm diagonally parked in a parallel universe.
FR700 is offline   Reply With Quote
Old 06-11-2015, 07:11 AM   #11
Carl Childers
Ghost in the Machine
 
Carl Childers's Avatar
 
Joined: Dec 2012
Location: Northern New Mexico
Oddometer: 924
Quote:
Originally Posted by davebig View Post
Dog damn lets hope not about the time one's into a rt a little too quickly and the chair is bouncing and very lite one needs a sensor that depowers the rig so you can head on the 68 Peterbilt with 90k on in he oncoming lane !!!!!!!!!!!!!!!!!

.......putting that way I think I'll stick with the old tried and true method!
__________________
New Mexico, not really new, not really Mexico.
Carl Childers is online now   Reply With Quote
Old 06-11-2015, 07:36 AM   #12
davebig
Another Angry Hun !
 
davebig's Avatar
 
Joined: Jan 2004
Location: Minnesota
Oddometer: 4,024
Quote:
Originally Posted by FR700 View Post
If you had an independently controlled sidecar brake, in combination with a trailing arm suspension, you would merely need to lightly drag the sidecar brake in order to get the chair suspension to 'squat', thus transferring weight to the chair. The fact that it also works as a cutting brake should also not be overlooked. A kinda twofer deal, if you will.


.
I've been trying to learn to feather the front in such situations, but I will admit last time it I didn't when I should have. I like the independent brake idea better than adding it to the rear, that early K/Escort brake was plumbed to the front and was easier.

Carl if you haven't scared yourself in a fast right yet you haven't been trying hard enough !
__________________
Patience: A minor form of despair disguised as a virture.
Ambrose Bierce
davebig is online now   Reply With Quote
Old 06-11-2015, 07:56 AM   #13
FR700
Heckler™©®
 
FR700's Avatar
 
Joined: May 2007
Oddometer: 8,458
Quote:
Originally Posted by davebig View Post
I've been trying to learn to feather the front in such situations, but I will admit last time it I didn't when I should have. I like the independent brake idea better than adding it to the rear, that early K/Escort brake was plumbed to the front and was easier.
Having three independent brakes is, in my not so humble opinion, the only way to go. The outfit only has one driven wheel (All you foil heads can put your hands down now. When was the last time you were doing 80 mph, or even just 45 mph, on bitumen in 2WD, all while negotiating a decreasing radius turn towards the chair? Thought so.). The reason being that you have far more control over the inertia that the chair develops.

That way you can reserve the front brake for turns away from the chair, and let inertia do some of the work for you.


.
__________________
I'm diagonally parked in a parallel universe.
FR700 is offline   Reply With Quote
Old 06-11-2015, 08:33 AM   #14
davebig
Another Angry Hun !
 
davebig's Avatar
 
Joined: Jan 2004
Location: Minnesota
Oddometer: 4,024
Quote:
Originally Posted by FR700 View Post
Having three independent brakes is, in my not so humble opinion, the only way to go. The outfit only has one driven wheel (All you foil heads can put your hands down now. When was the last time you were doing 80 mph, or even just 45 mph, on bitumen in 2WD, all while negotiating a decreasing radius turn towards the chair? Thought so.). The reason being that you have far more control over the inertia that the chair develops.

That way you can reserve the front brake for turns away from the chair, and let inertia do some of the work for you.


.
Your not going to get an argument from me !
Trouble being these ol guys here in adv forum are not trying to double the posted cornering speeds with a GS based rig or they would handle allot better !

If they spent much time with a decent road rig they would all get an idea what's possible.
__________________
Patience: A minor form of despair disguised as a virture.
Ambrose Bierce
davebig is online now   Reply With Quote
Old 06-11-2015, 09:05 AM   #15
jeffjbmw OP
Threadkiller
 
jeffjbmw's Avatar
 
Joined: Aug 2006
Location: Magdalena, NM
Oddometer: 893
To start, I took the bathroom scale and placed it under the hack wheel to see what the force is with the car empty. 141 pounds.

It is a R1150RS coupled to a DMC M72B.

Next, I need a way to put something that measures force between the swing arm and body of the car.....
__________________
You can never have too many motorcycles and musical instruments. But if it is only one of each....... a R1200GS. And a Martin 00-18H......

Read my blog: http://jeffszen.blogspot.com/
jeffjbmw is online now   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

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 On

Forum Jump


Times are GMT -7.   It's 07:43 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2015