Side Car Questions

[ferball]

Okay, blame Silver Bear for this thread, but his sidecar project has made me switch gears from my trailer project to a side car. So before I get to deep into it I want to do my research. I've search the internet and scoured this forum for anything pertaining to side cars and found some cool pictures and interesting ideas. I still have a few questions that I am sure they have been answered but I could not find them. So here goes:

Rigid versus flexible mount. What little I have found out about sidecars usually pertains to motorcycles and rigid versus lean seems to be an ongoing debate, usually coming down to personal preference. On the bike side of things I have seen lots of both. Has anyone experienced both? Or is there a reasin I should go with one and not the other because Motorized Bikes are not Motor Cycles?

Weight. I am planning to have a side car with a capacity of at least a 100 lbs so the hack it self will be fairly robust, on a trailer most of the weight resides on the axle if loaded and constructed properly. So in a trailer situation not a lot of additional strain on the bike itself except from a towing perspective. A side car shares half the weight with the bike, and my plan is to attach the side car to the chain stay, will weight need to be considered or is the chain stay strong enough that unless I am hauling elephants there is nothing to worry about.

Those are my two big questions so far, and hopefully I get some good feed back and create the "definitive" side car thread.

 

[mountain80]

From my perspective go with an all aluminum frame, If built correctly and reinforced it can be both strong and light. You can bolt the sections together to avoid welding and a plus is that if you brak a part or find it is not strong enough you can unbolt it and replace a single part/section fwiw.

 

[silverbear]

Ah, the madness spreads. Excellent! I can't wait to see what you come up with and how it works out. I have no answer to your questions as I'm just winging it. Fasteddy knows a lot about this stuff, so mayber he'll weigh in. The Watsonian sidecars from the old days in England were designed for bicycles and not motorcycles and they pivoted. Without knowing from experience, it sounds to me like pivoting or flexing is a good idea so that's what I'm aiming for. I guess we'll find out. Fun, eh?
SB

 

[ferball]

I stumbled across Watsonians last night while researching.

Watsonian Sidecar Images - Gentleman Cyclist | Google Groups

The design is incredible simple. I have some ideas about how to design the pivot connection, and i figure once the frame is done make a cool looking box to put on top of it, and stick my kid in it.

I still have concerns about connecting to the chain stay, I figure I have about a five inch span between the crank and rear derailer. Will that five inches be enough to over come the torque of the cars want to pivot on the axle, and will that cause undo weight/stress on the bike? I will find out soon enough when I make it, but I was hoping that an engineer here could quiet my fears.

 

[silverbear]

Those are some great images and provide a lot of food for thought. Why try to reinvent the wheel if we don't have to? i can see where the derailleur would reduce the room for the attachment there. I don't know the answer to that one, but I can see that on a single speed cruiser or a bike with an internal hub this would be slick. I think Fasteddy's setup is very similar to the Watsonian. I'm also thinking that my little bicycle trailer wouldn't be much heavier than it is with aluminum panels instead of the fabric. And some of the images are reminiscent of a canoe front end as I've been thinking about for the next sidecar. Now I have an inkling of what fun fasteddy has been having with his sidecar. These are so cool! Thanks for sharing. I've taken the liberty of snitching some of the photos and posting them below.I notice that the sidecar wheel is running in line with the rear wheel of the bike. The one I'm working on is forward of the bike's rear wheel. I wonder what effect that will have? Also in the final photo it looks like the rear of the sidecar is swinging out as it turns. Does the rear most attachment telescope?
SB

 

[chainmaker]

While researching sidecars a few months ago I found this link here A Bicycle Sidecar to have some pretty good info.
Cheers

 

[ferball]

Well I started my side car frame today, I still have to reinforce the bar that attaches to the gike as the materials I used won't handle the torsion in its current configuration, and I still have to figure out my pivot mount, which is in my head but implementation with available materials my be tricky. Not near as cool as some I have seen, but no welding required so far and the material is some left over angled steel stuff from some shelving, but can also be bought fairly cheap at home depot.

 

[silverbear]

Well I started my side car frame today, I still have to reinforce the bar that attaches to the gike as the materials I used won't handle the torsion in its current configuration, and I still have to figure out my pivot mount, which is in my head but implementation with available materials my be tricky. Not near as cool as some I have seen, but no welding required so far and the material is some left over angled steel stuff from some shelving, but can also be bought fairly cheap at home depot.

All right! Looks like you won't have to drill any holes in the frame. What size wheel are you using?
SB

 

[ferball]

I am looking at a 16" wheel from my sons old bike (luckily he out grew it this year so I can use it for parts) But I did leave enough space in the frame to go as large as 26" if I need to, but I don't think I can get it to sit level if I go that big.

 

[ferball]

Scored some wheels today, a destroyed instep jogging stroller rescued from the curb trash. Won't be able to tinker for a few more days, but the torque on the single connecting arm still bothers me. While wandering through Lowes today looking for tulips for moms day, I noticed the front wheels on a Z turn mower. I was thinking something like that on the front of the side car would take away the torque and still enable turning. But it complicates it and starts getting expensive, but just a thought.

 

[corgi1]

I believe the wheel is straight accross from the rear wheel of the bike so the side car wheel dosen't have to slide side-ways when you turn