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bmcsheehy



Joined: 22 Jan 2005
Posts: 977
Location: Massachusetts USA

PostPosted: Mon Apr 11, 2005 1:19 pm    Post subject: Reply with quote

Sorry arbalest, didn't mean to come across arrogant or argumentive. Buddies
I think the best way to get the price down is to get more people really interested in them.
Not just tire kickers but people that truly want one. I think it's going to be a long process, but if any one drives one, theyíre going to want one.
Then maybe sidecar manufactures in this country will design and build them. Give the people what they want. Hannigan is the first.

http://www.inb.net/hannigan/content/bandito.html

Maybe even other countries will cater to the US too. Question
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Bill
High Performance Sidecaring... ...There is nothing "HACKED" about it.
2006 ZX-14 / HANNIGAN HP.
2011 Concourse / California Friendship III.
1936 Ford Fordoor Humpback
www.Yankee-Engineering.com
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arbalest



Joined: 01 Feb 2005
Posts: 92
Location: Windham

PostPosted: Mon Apr 11, 2005 2:29 pm    Post subject: HP sidecars Reply with quote

Bill, I didn't take your post as arrogant or argumentative. You make very good points. I guess I am just looking for a simpler way to get to the same place regarding true c.h.s. I am so envious of you....although most people who work at a trade(I know I'm generalizing...) don't play in the sandbox that they work in. It must be nice to have the tools and the knowlege to make what you can't buy.
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Tue Apr 12, 2005 2:10 am    Post subject: Reply with quote

Hope all this makes sense but we have some terms being used here that may be a little out of kilter Smile Someone please correct me if I am wrong.

Scrub RADIUS, on a center hub system, is the difference between the pivot point of the steering axis and the center of the tire that is turning around it when viewed from the front or rear. If these two points are at the same place there is zero scrub radius.

Center hub steering is an effort to create zero scrub radius. This can be accomplished by the king pin inclination angle being such that a line drawn through it, viewed from the front or rear, intersects ground level at the center point of the tire. Center hub steering can also be accomplished by placing the upper and lower ball joints directly above one another and in line with the centerline of the tire when viewded from the front or rear.Doing it this was is often referred to as 'true center hub steering'.


If there is a scrub radius on a rig it will theoretically cause it to pull to the side that it is on. (Other factors, of course , come into play but in speaking of the scrub radius alone this is the result)
On a regular automobile the reason some have a scrub radius built in is to give more 'feel' to the steering. Tire wear is not really an issue because of this for the same basic reason it is not an issue due to toe in ON A CAR. The slip angle of the tire (think of it as sidewall flex) pretty much takes the concern away.Not all cars have a scrub radius. I had mentioned this in an earlier post.

Correct me if I am wrong but I think Bill was talking more about camber change due to static caster ( basically the same as trail on a conventional motorcycle front end or a leading link) in the front end.( I am not familiar with the term 'scrub angle').
In essence the more caster there is the more the tire leans when the wheel is turned. It is possible to design in caster which will not affect camber by playing with the spindle location in relation to the steering axis as viewed from the side. This is used on some cars to varying degrees.. (Corvette is one of them).
Bottom line of all this mumbo jumbo is that on a rig with a single steering tire it is felt best, by many, to be able to have a zero scrub radius. There may be some advantages to playing with this as an adjustment. Some have tried with varying results.
The idea of any benefits or downfalls to adjusting the caster as related to a zero degree steering axis is still up in the air. As we move ahead (?)this may be interesting to see just how it does affect an outfit.
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Claude Stanley

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

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Tue Apr 12, 2005 4:19 am    Post subject: Reply with quote

This article is related to four wheel cars but if it is read with a mindset towards the advantage of center hub (center point) steering on an outfit it may take some of the mystery out of it.
click here:
http://tinyurl.com/3p3xw
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Claude Stanley

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

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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bmcsheehy



Joined: 22 Jan 2005
Posts: 977
Location: Massachusetts USA

PostPosted: Tue Apr 12, 2005 11:11 am    Post subject: Reply with quote

Moron Alert
Once again, Claude is right. I guess I was talking about static caster. Didnít mean to try and answer the wrong question.
After reading the article, I have to agree with Claude. TCHS does away with scrub radius. We need to because there is no other front wheel to compensate for it.
I suppose you could compensate with the sidecar wheel with toe in or out. That would drastically effect tire wear on the sidecar.
The steering axis runs through the middle of the wheel, left to right putting the Dave spot in the middle of the tire, left to right.
Depending on how the suspension was built, the Dave spot should not change left to right as your driving. Otherwise the rig theoretically would pull left or right.
The terminology can real get confusing. Not sure if Iíll ever remember what is what.
One thing for sure, you canít just bolt some pieces together and expect them to work properly.
Not to say that you canít use off the shelf items, as long as they are connected together properly, It could work.
I donít think I have the time or the patience to locate all the parts that would work.
When I built mine, I did use as many off the shelf items as I could; Ball joints, tie rod ends, axel assembly, calipers, rotors, sway bar mounts. Also some stuff you can buy at hardware stores, bronze bushings, nuts, bolts, washers, spacers, rodends, split collars, etc.
Then just connected the dots with tubing. Big Grin
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Bill
High Performance Sidecaring... ...There is nothing "HACKED" about it.
2006 ZX-14 / HANNIGAN HP.
2011 Concourse / California Friendship III.
1936 Ford Fordoor Humpback
www.Yankee-Engineering.com
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Tue Apr 12, 2005 10:18 pm    Post subject: Reply with quote

Bill ,
I must commend you for the work you have done on your HPS rig. Also it is exciting and encouraging to read your posts and candid thoughts on it.
Suspension and steering dynamics are all about geometry. It can be made to sound real technical but in reality it is all a big compromise that has to be designed around a few absolutes.
I admire the efforts of some of the 'pioneers' into the HPS world here in this country. Don't get me wrong, the Europeans are highly admired as well but it is exciting to see some rigs being built, and now marketed, in our own backyard. Face it, We have been behind the times as far as sidecar technology has gone for a long time.
It is also very exciting to have this site that is dedicated to
HPS rigs from all over the world. A place to exchange thoughts and ideas as well as riding experiences. I hope this site prospers and grows for many years to come.
To all here I just want to say Thank You
Claude..man was that corney or what..whew.
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vintagegear



Joined: 26 Nov 2005
Posts: 14
Location: Portland. Oregon. USA

PostPosted: Thu Feb 01, 2007 8:42 am    Post subject: Reply with quote

I know this is an old thread, but I've been reviewing the idea of using automotive suspension vs wholly fabricated parts. Confused
Corvette components are fairly suited to the role, if just a little bulky:



Caster is fairly pre-set on automotive components, so 'off the shelf' parts would probably require a custom knuckle for use out front.
Still, these might offer some value on the sidecar in the ease of adjusting lead. If a sliding mounting were used, lead would only be constrained by the style of fender. Toe-in would be easily adjustable as well. FWIW: I think the change in camber while under load might be an asset. The compromises would be in interior space and styling. Caster could also be a benefit where fractional side steering was employed. Not good for sway bars though...

Ben
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Fri Feb 02, 2007 10:06 am    Post subject: Reply with quote

Harry Tarzian (814 349 2414) recently built a CHS that uses a corvetter spindle assembly on it for his own rig. It does not have the conventional automotive a frames though as in your picture.
There have been sidecars pictured here with a frame suspensiosn for the front of the bike where the a frames were pivoted off the bike side frame rail of the sidecar.
I would love to build one like that someday using off th eshelf parts either from the auto world or the racing fraternity suppliers. There are lots of options to choose from in either arena..
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Claude Stanley

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

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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kiltedfireman



Joined: 25 May 2008
Posts: 9
Location: Harvard IL USA

PostPosted: Wed May 06, 2009 4:06 am    Post subject: resurrecting a dead thread Reply with quote

Sorry to resurrect a dead thread, but I have a couple questions about TCHS in general and A-Arm in particular.

I can't see the pic of the corvette spindle anymore, but I think I remember it having the spindle offset from the ball joints. It made me think, why do we need caster/rake if we can get the necessary trail without it? What if the ball joints were directly above each other (no caster) but while being in the middle of the tire tread side-to-side (CHS with no scrub radius), were positioned so that the line through them intersected the ground (the Dave Point) ahead of the middle of the contact patch?

As was pointed out here somewhere, caster results in the edge of the tire being picked up when wheel is turned. If we had no caster, wouldn't the tread stay flat as it was turned? Question

Add in some equal length A-Arms and you don't have any camber change as the wheel goes up and down. True, it does pull in and out a little bit but would it matter in the grand scheme of things?

Tony Foale did some experiments some time ago with a beemer where he mounted the stock fork straight up and down with a frame built off the front of the stock frame. It looked funny with the fork so far out in front of the bike, yet it still had manageable trail for stability. I seem to remember him saying if felt completely normal other than the increased stiction inherent in tube forks. With an alternative suspension it wasn't an issue.

I don't think it could be done with both ball joints within the wheel, but isn't it still TCHS if the bottom ball joint is within the wheel and the upper one is ABOVE the tire? It would be a tall spindle with a big bend in it, but so what?

Here's something crazy, use a front driver spindle modified, then use a shortened drive axle to transfer brake forces to an inboard brake! complicated, but less sprung weight! And what is sidecarring about if not mastering futile mechanical engineering feats! I mean, if it were just about going fast simply, we'd all buy Miatas and save a ton of money! Laughing

Sidecar Denny, still rocking an old BMW/EML setup with the tiny 125 tires...
sidecar.denny@gmail.com
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bmcsheehy



Joined: 22 Jan 2005
Posts: 977
Location: Massachusetts USA

PostPosted: Wed May 06, 2009 11:14 am    Post subject: Re: resurrecting a dead thread Reply with quote

These are only my opinions, please do not take offence. Buddies
Everything you have said sounds correct.
When are you going to start?
Would like to see some pictures.

kiltedfireman wrote:
Sorry to resurrect a dead thread, but I have a couple questions about TCHS in general and A-Arm in particular.

I can't see the pic of the corvette spindle anymore, but I think I remember it having the spindle offset from the ball joints. It made me think, why do we need caster/rake if we can get the necessary trail without it? What if the ball joints were directly above each other (no caster) but while being in the middle of the tire tread side-to-side (CHS with no scrub radius), were positioned so that the line through them intersected the ground (the Dave Point) ahead of the middle of the contact patch?

Yes, you are correct. The trail can be created exactly as you described. I think having the trail increase as the suspension is used up, like under hard braking, makes the rig more stable.

kiltedfireman wrote:
As was pointed out here somewhere, caster results in the edge of the tire being picked up when wheel is turned. If we had no caster, wouldn't the tread stay flat as it was turned?

Yes. But, with some scrub radius or static caster, the edge of the tire may lift slightly when turning, but as the tire rolls back under when cornering the tire is flat again. If there is no scrub angel then as the tire rolls under when turning the opposite edge would be lifting off the ground. So scrub angel helps to compensate for G force and keeps the tire flat on the ground.


kiltedfireman wrote:
Add in some equal length A-Arms and you don't have any camber change as the wheel goes up and down. True, it does pull in and out a little bit but would it matter in the grand scheme of things?

Probably would not matter.

kiltedfireman wrote:
Tony Foale did some experiments some time ago with a beemer where he mounted the stock fork straight up and down with a frame built off the front of the stock frame. It looked funny with the fork so far out in front of the bike, yet it still had manageable trail for stability. I seem to remember him saying if felt completely normal other than the increased stiction inherent in tube forks. With an alternative suspension it wasn't an issue.


kiltedfireman wrote:
I don't think it could be done with both ball joints within the wheel, but isn't it still TCHS if the bottom ball joint is within the wheel and the upper one is ABOVE the tire? It would be a tall spindle with a big bend in it, but so what?

Yes, trying to get everything inside the wheel is the challenge. I guess that would fall under the builders preferences. I like the look of compact and neat. Cool

kiltedfireman wrote:
Here's something crazy, use a front driver spindle modified, then use a shortened drive axle to transfer brake forces to an inboard brake! complicated, but less sprung weight! And what is sidecarring about if not mastering futile mechanical engineering feats! I mean, if it were just about going fast simply, we'd all buy Miatas and save a ton of money!

Already been done, I am not a Mazda man, Maybe a Honda S2000. Big Grin
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Bill
High Performance Sidecaring... ...There is nothing "HACKED" about it.
2006 ZX-14 / HANNIGAN HP.
2011 Concourse / California Friendship III.
1936 Ford Fordoor Humpback
www.Yankee-Engineering.com
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kiltedfireman



Joined: 25 May 2008
Posts: 9
Location: Harvard IL USA

PostPosted: Wed May 06, 2009 11:52 am    Post subject: no problem Reply with quote

Hi Bill,

Nothing offensive said, so no offense taken!

Well, this won't be started too soon. I'm hoping my divorce is finished in the near future, and I have to give the ex 50% of my pay for the next four years. That will impact how quickly things happen.

This thought process all started as I tried to figure out ways around the limitations of my current rig. The tires are so small (but at least they're expensive!) that I wanted to widen the wheels, then how do you alter the LL fork and the swingarm, etc,

Then I realize that it's always going to be an airhead that doesn't like going more than 65 or so, so enjoy it for the period piece it is and build something newer and higher-tech. So what tug to use, and if I weren't being held down by the limitations of what I'm already doing? etc.

And so it goes....Thanks for giving me things to dream about!

Denny
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Paul



Joined: 27 Jan 2005
Posts: 182
Location: Utah

PostPosted: Wed May 06, 2009 4:56 pm    Post subject: Re: resurrecting a dead thread Reply with quote

kiltedfireman wrote:
It made me think, why do we need caster/rake if we can get the necessary trail without it?


Doesn't caster/rake give directional stability? i.e. the rig goes straight when you take your hands off the bars? With no rake I think just keeping the rig going down the highway would take a lot of effort.

kiltedfireman wrote:
I mean, if it were just about going fast simply, we'd all buy Miatas and save a ton of money!


Miatas are fun and all, but I *really* hope the definition of "High Performance Sidecar" includes a clause saying it must be faster than a Miata.
Sure it has the power of a Hayabusa - but it weighs 2,400 pounds - so a HPS should have at least double the power/weight ratio.
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swaybar2002



Joined: 26 Jan 2005
Posts: 380
Location: Central Pa.

PostPosted: Wed May 06, 2009 9:10 pm    Post subject: Reply with quote

Hello all...good to see you all again. Been busy here but that is not a bad thing.
Anyhow.....Bill B. asked me to post so how about thinking on this and seeing if I am all wet. I think kiltedfireman is on the same page as I was here previously as far as the caster- vs- trail ideas go.
Look at the front wheel steering pivot points from a side view. The top one is typically behind the lower one to create caster and the spindle is on a line between these two points. The angle ( degrees) of the caster dictates the amount of self centering effect we have when coming out of a turn. The angle of the caster also dictates the amount of camber change we have when the wheel is turned.
So more caster angle or degrees equals more self centering, more camber change when turning and of course harder steering.
We run less caster in order to make steering easier but it also reduces camber change when turning the front wheel.
What if we could still get the benefits of reduced caster to a point we wanted it and have a possible zero camber change when the front wheel is turned.
Now, again, imagine a front end ,looked at from the side like above, but now where the steering pivot points are directly above one another. Zero caster? That'll never work. But..... what if the spindle itself was behind the steering pivot points (This is how the previously mentioned Corvette spindle member is built). Maybe this would be called 'trail'. With zero caster and 'X' amount of 'trail ' would not we have a self centering effect but without any camber change when the wheel is turned. If that is so then we coudl dial in say a degree or two of caster and still have a little camber change if we felt it was a good thing in cornering.
I am not convinced that more caster is not good in cornering, especially with one ply sidewall tires, but that is another story.
Make sense? Not sure myself.

Oh, click here for the article by Faole referred to previously by kiltedfireman
http://www.tonyfoale.com/Articles/RakeEx/RakeEx.htm
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Claude Stanley

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

2007
I.S.O.K Sidecar RON-DEE-VOO III ..
First full weekend in August!! Thursday through Sunday!!
Weikert, Pa ..more details coming
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kiltedfireman



Joined: 25 May 2008
Posts: 9
Location: Harvard IL USA

PostPosted: Mon May 11, 2009 10:04 pm    Post subject: A-Arms, caster and camber Reply with quote

Claude, Bill, and all,

Thanks for the link to Foale's article, that is exactly what I was talking about. Claude, you and I are on exactly the same page with this.

I'm not sure myself if caster or rake is necessary at all. I think it is a description that is used because you can see it, unlike trail which is a couple imaginary points on the ground. Foale seems to have proved that it is trail that gives the self-centering effect, rake was simply the way to adjust it on a standard motorcycle, with triple-tree offset and leading or trailing axle on the telescopic sliders giving the designer some minor adjustability of the resulting trail.

Rake on a standard motorcycle frame is tied to trail by design (ie, the steering axis turns through the headstock of the frame, giving you the line to the ground for the first point to measure trail from.) You can't eliminate rake/caster without eliminating trail unless you go to the lengths Foale and Willoughby did.

Foale's experiments found that reduced rake (to about 15 degrees) made the motorcycle wholly more enjoyable and steady to ride, it only was bad for braking with a telescopic fork.

This is even more exciting for us as sidecarists, as we like less trail as a rule than two wheelers. If reducing the rake/caster can keep the tire flatter in turns ( important for us flat-turning sidecarists, not a concern to a leaning two-wheeler) while still giving us enough trail for stability, it would seem to be having your cake and eating it too!

Bill, am I understanding correctly that by having what is in effect a forward-facing unequal length A-Arm suspension, what would be a camber change from the side becomes a caster (and hence trail) gain under compression of the suspension?

It seems to me this untying of rake/caster from trail might even make the leading link fork more useful than it has been. The earles fork or a Foale design (very similar to BMW's Telelever) doesn't have the same bending issues as a telescopic, so it would be much better suited to the steeper rake of the Foale experiments. It still would necessitate the heavy headstock in the frame as all the suspension loads are being transmitted through it, unlike what we are describing here as CHS/TCHS.

I'm not aware of anyone having experimented with this because LL forks are mostly used to convert existing frames to better sidecar use; has anyone modified or designed a traditional style frame to use LL from the get go and made it with the headstock angle good and steep? Might there be a benefit from LL that TCHS doesn't give? What kid of suspension travel are you guys with TCHS front ends getting? The biggest drawback to steeper rake on a standard frame with fork-type suspension would seem to be the one Foale points out; it makes remote steering almost a necessity, unless you have gorilla arms. Of course, you have remote steering with a TCHS also to some extent.

Has anyone else seen the Parker/RADD front end developments in Motorcyclist? He is now using bearings meant for a CNC machine to give him telescopic steering to the upright on his CHS front end for sportbikes.

I'd be really interested in hearing how much caster, trail, and suspension travel you guys have in your TCHS style rigs. I live in Chicago, where the roads are flat and straight and pockmarked like the face of the moon. I don't have a Pacific Coast Highway or the Dragon to contend with. What I DO need is a decent amount of suspension travel.

Thanks for the discussions, I've learned a ton reading all the old posts.

Denny, the kilted fireman
sidecar.denny@gmail.com
"When the going gets weird, the weird get going"[
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docmike



Joined: 27 Jan 2005
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Location: Eastern NC

PostPosted: Tue May 12, 2009 3:58 pm    Post subject: Reply with quote

Just a few thoughts,

Quote:
I think having the trail increase as the suspension is used up, like under hard braking, makes the rig more stable.


On a solo bike it is the reverse, hard braking reduces trail, making the bike easier to turn and is considered an advantage when setting up for a corner.

Quote:

kiltedfireman wrote:
Add in some equal length A-Arms and you don't have any camber change as the wheel goes up and down. True, it does pull in and out a little bit but would it matter in the grand scheme of things?

Probably would not matter.



Would camber change be a bad thing? Certainly on a solo bike you would not want it, however with these wierd three wheelers we ride maybe some camber change, similiar to what goes on in a car front suspension might be good.

Mike
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