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 03-22-2015, 04:10 AM   #1
Sunus OP
Adventurer
 
Joined: Mar 2014
Oddometer: 12
Home made leaner handling PROBLEM

Hello,

I found this great forum, after I got an idea to build leaner sidecar. I am in the middle stage and I got a problem with handling.
THe bike is Yamaha XV1900 Raider. It is big and heavy bike with long front forks. I have made a subframe in the middle of the bike under the engine, front is raised by 12 cm. i have connected sputnik sidecar, but when i made first test drive i found out that my handlebar is shaking even on low speeds and its kind of heavy to turn. when i was trying to turn around i got a feeling that front tire is sliding a bit, that give a feeling of unstability. Also when accelerating my whole bike was pulled toward sidecar and when released accelerator bike was pushed against sidecar. What could be a reason of that? tomorrow i will upload some pictures.
some notes:
1.the links from the sidecar does not hit the subrame by 90degrees.
2. i did not make wheel adjustment yet
3.rear wheel axle is backwards from the sidecar wheel axle by 20cm
4.sidecar weights around 100kg empty

Waiting for the comments, hopefully it will be more clear when i will upload the pictures
Sunus is offline   Reply With Quote
Old 03-22-2015, 05:15 AM   #2
Chinookmark
Gnarly Adventurer
 
Joined: Oct 2005
Location: New Hartford, CT
Oddometer: 265
You raised the front of the bike 12cm? Did you also raise the rear? That could cause funny handling issues by creating too much trail in the front geometry, especially with a chopper/cruiser style bike that tend to already have a lot of trail.

I have zero experience with leaners, and very limited sidecar experience at all, but I am making the assumption that leaner geometry will be similar to a two-wheel motorcycle.

Side note- We need pics!
Chinookmark is offline   Reply With Quote
Old 03-22-2015, 05:18 AM   #3
claude
Sidecar Jockey
 
Joined: Mar 2002
Location: Middleburg, Pa. (Snyder County)
Oddometer: 3,782
You will get a pendulum effect on acceleration and deceleration due to the weight of th sidecar on the one side of the bike. The heavier the sidecar the more you will feel this. Did you try it without the body on the sidecar frame? Were are you located?
__________________
Claude

Founder: Internet Sidecar Owners Klub at SCT
http://autos.groups.yahoo.com/group/SCT/

President: C Stanley Motorsports Inc.
http://autos.groups.yahoo.com/group/...rsandTrailers/

http://freedomsidecars.com/
claude is offline   Reply With Quote
Old 03-22-2015, 05:23 AM   #4
claude
Sidecar Jockey
 
Joined: Mar 2002
Location: Middleburg, Pa. (Snyder County)
Oddometer: 3,782
When you say you raised the from are you talking about the front mount in relation to the rear mount? If so this is common with a leaner as it ;steers; the sidecar wheel as the bike leans in the direction you are turning. This is okay unless overdone as it can cause difficulty in exiting the turn.
You have what could make a decent combination as a rigid as far as bike and sidecar go if you decide to go that route.
__________________
Claude

Founder: Internet Sidecar Owners Klub at SCT
http://autos.groups.yahoo.com/group/SCT/

President: C Stanley Motorsports Inc.
http://autos.groups.yahoo.com/group/...rsandTrailers/

http://freedomsidecars.com/
claude is offline   Reply With Quote
Old 03-22-2015, 05:25 AM   #5
FR700
Heckler™©®
 
FR700's Avatar
 
Joined: May 2007
Oddometer: 7,662
Quote:
Originally Posted by Chinookmark View Post
You raised the front of the bike 12cm? Did you also raise the rear?
His, well I'ma guess on that one, may also be a female, no, not both male and female simultaneously... but I digress... vertical separation between the two pivot points is currently 120 mm.

Quote:
Originally Posted by Sunus View Post
Hello,

I have made a subframe in the middle of the bike under the engine, front is raised by 12 cm.


.
__________________
I'm diagonally parked in a parallel universe.
FR700 is offline   Reply With Quote
Old 03-22-2015, 05:29 AM   #6
FR700
Heckler™©®
 
FR700's Avatar
 
Joined: May 2007
Oddometer: 7,662
Quote:
Originally Posted by claude View Post
You will get a pendulum effect on acceleration and deceleration due to the weight of th sidecar on the one side of the bike. The heavier the sidecar the more you will feel this. Did you try it without the body on the sidecar frame? Were are you located?

All good, valid points.

Track is something that has also not been disclosed at this point.


.
__________________
I'm diagonally parked in a parallel universe.
FR700 is offline   Reply With Quote
Old 03-22-2015, 05:32 AM   #7
xrocket
Adventurer
 
Joined: Aug 2011
Oddometer: 49
A very good place to start ...

The above Hack Forum Sticky ... Sidecar Design formula.

Well worth your time investment.

Oodles of useful info.
__________________
xrocketism : Slow down before turn in, Late apex for safety out, Gas to go right, Brake to go left, Get it backasswards and it just won't matter anymore...
xrocket is offline   Reply With Quote
Old 03-22-2015, 05:40 AM   #8
claude
Sidecar Jockey
 
Joined: Mar 2002
Location: Middleburg, Pa. (Snyder County)
Oddometer: 3,782
Quote:
Originally Posted by FR700 View Post
All good, valid points.

Track is something that has also not been disclosed at this point.


.
Yes,,,the wider the track width the more pendulum effect will be happening. Note to all ...With a leaner track width is decided by lean angle requirements, Handlebar width etc.. The larger the sidecar the wider it may have to be depending in body style. Running out of lean angle in a turn toward the sidecar can be a little unnerving. It can be dealt with by those with experience but gaining that experience can create some valid 'pucker moments' at best.

Question to OP: Do you have a means to 'lock up' your leaner for low speed maneureving?

John Goff is a guy who comes to mind when I think of leaners. He is heavy into Flexit leaners but may be able to help too. Haven't spoken to him in a long time. Hopefuly he lurks here ..dunno . JOHN are you here ?? LOL. Email is: E-mail John at: jg@teleport.com If you contact him say hello from Claude and tell him to join into this discussion here :-)
__________________
Claude

Founder: Internet Sidecar Owners Klub at SCT
http://autos.groups.yahoo.com/group/SCT/

President: C Stanley Motorsports Inc.
http://autos.groups.yahoo.com/group/...rsandTrailers/

http://freedomsidecars.com/

claude screwed with this post 03-22-2015 at 05:54 AM
claude is offline   Reply With Quote
Old 03-22-2015, 08:45 AM   #9
Chinookmark
Gnarly Adventurer
 
Joined: Oct 2005
Location: New Hartford, CT
Oddometer: 265
Quote:
Originally Posted by FR700 View Post
His, well I'ma guess on that one, may also be a female, no, not both male and female simultaneously... but I digress... vertical separation between the two pivot points is currently 120 mm.





.

Oops. Misinterpreted which part was raised.

Still want pics though!
Chinookmark is offline   Reply With Quote
Old 03-22-2015, 09:04 AM   #10
cleatusj
Dirt floor engineer
 
cleatusj's Avatar
 
Joined: Dec 2010
Location: Granbury, TX
Oddometer: 1,175
When mine was setup as a leaner, scrub was felt most at slow speeds. I consider slow below 20mph. The pendulum effect is something you adjust for after very little experience.
__________________
In the stable now. '76 Moto Guzzi Convert Hack
'93 Moto Guzzi Calli 3 with Leaner turned rigid
'99 WR400F
Hack build: http://www.advrider.com/forums/showt...rt+floor+build
cleatusj is offline   Reply With Quote
Old 03-22-2015, 12:34 PM   #11
Sunus OP
Adventurer
 
Joined: Mar 2014
Oddometer: 12
Quote:
Originally Posted by Chinookmark View Post
Oops. Misinterpreted which part was raised.

Still want pics though!
The difference between rear pivot and front pivot point is 120mm. (vertical). That is what I have found on forums for leaner rig to handle.
But does the sidecar wheel should be parallel to the motorcycle wheels or it should have some turn into motorcycle like in fixed sidecars?
Sunus is offline   Reply With Quote
Old 03-22-2015, 12:40 PM   #12
Sunus OP
Adventurer
 
Joined: Mar 2014
Oddometer: 12
Quote:
Originally Posted by claude View Post
You will get a pendulum effect on acceleration and deceleration due to the weight of th sidecar on the one side of the bike. The heavier the sidecar the more you will feel this. Did you try it without the body on the sidecar frame? Were are you located?
I am located in Lithuania, (Europe). I have made a test drive with the body on the frame empty, also with the 80kg person inside. The pulling effect was bigger with the person inside. I will make pictures and hopefully video tomorrow.
Sunus is offline   Reply With Quote
Old 03-22-2015, 12:50 PM   #13
Sunus OP
Adventurer
 
Joined: Mar 2014
Oddometer: 12
Quote:
Originally Posted by claude View Post
You will get a pendulum effect on acceleration and deceleration due to the weight of th sidecar on the one side of the bike. The heavier the sidecar the more you will feel this. Did you try it without the body on the sidecar frame? Were are you located?
but the sidecar is pushed by the central axle of the motorcycle (subframe is in the center), so it should not be such effect. when it is connected to the side of the frame like in URAL, than I has this pulling effect, that is why there is steering damper and sidecar wheel looks towards motorcycle.
but why Kalich makes sidecars out of plastic and reaches as low as 70kg weight. possibly due to same reason
Sunus is offline   Reply With Quote
Old 03-22-2015, 12:58 PM   #14
FR700
Heckler™©®
 
FR700's Avatar
 
Joined: May 2007
Oddometer: 7,662
Quote:
Originally Posted by Sunus View Post
but the sidecar is pushed by the central axle of the motorcycle (subframe is in the center), so it should not be such effect. when it is connected to the side of the frame like in URAL, than I has this pulling effect, that is why there is steering damper and sidecar wheel looks towards motorcycle.

You overlook the obvious.

The outfit is driven by ONE wheel. When you take off or accelerate the sidecar wheel will lag = bike turns to sidecar.

When you slow down the engine braking is only applied to ONE wheel. The bike's rear wheel. = sidecar wheel has inertia and is now free to do its own thing = sidecar turns toward bike.

Pendulum effect, whether you like it or not. Rigid or leaner makes no difference. Physics is physics.


.
__________________
I'm diagonally parked in a parallel universe.
FR700 is offline   Reply With Quote
Old 03-22-2015, 01:15 PM   #15
Hellracer.nl
What the hack???
 
Hellracer.nl's Avatar
 
Joined: Aug 2012
Location: Netherlands
Oddometer: 436
Hi Sunus, I have a homebuild leaner as well. Mine does pull a little under hard acceleration but nothing dramatic. Hard breaking with a full sidecar can be challenging but with a little anticipation all is well, again nothing that can't be dealt with.

I suspect that the long frontfork legs and low build frame aren't helping in this configuration, Kalich prefers to use high build motorcycles like GS 1200's and such.

I have a little toe in, this keeps the pulling to a minimum at higher speeds. I can ride at 140km/h with one hand on my steer.
__________________
To beer or not to beer, that's no question.


My Leaner build: http://advrider.com/forums/showthread.php?t=836987
K1100rs, K100rs, F650, GSX1100, TS185
Hellracer.nl is offline   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 06:22 PM.


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