Weight for sidecar w/out passenger

Hi Bill:

I ran a Formula I on a K1100LT Bmw for 20+ years.  I had it come up 3 times on me.  Once when I was expected to do it for sidecar certification. The other two times were when I dropped the sidecar wheel into a pothole on the inside of a right hand turn and when the wheel came out of the hole the car flew for a few feet. 

For the certification class they used the reasoning that you needed to know what to do when those times happen. The bike becomes a 2-wheeled vehicle for a moment and you just straighten the handle bars and the sidecar come back down.  When it happens your hope is that there is no one coming at you because you might swerve into the oncoming lane.

A simple solution is a bag or two of softener salt if you think you need some ballast.  

I hope my experience gives you some comfort.

Will Short

Ex-president USCA

I run the FII on my 1500 Wing, I find it stays down very well due to it's weigh and wide stance. But I also live in an area where the closest thing we have to twisties is a couple mean off ramps.  I don't add ballast but I do have a 6 gal fuel tank behind the seat so it always has some added weight. I will say however it does ride much better with some more weight when no passenger is riding. for me about 50 lbs seems to be the magic number to smooth the ride out if I were to want to add the weight. you really just need to experiment and find that sweet spot for your riding comfort, style and conditions 

does your venture have the easy steer, if not I happen to have one for sale 

To tell if a sidecar is heavy enough for you. Step on the out side foot peg/floor board, turn the handle bars towards the sidecar then pull back. If you can get the sidecar to just barely come off the ground you are fine. It it comes up easy add ballast. More goes into how much ballast a person needs then just the sidecar, what bike it is on, how high up the bike carries its weight, where and how the sidecar carries its weight, I.E. a heavier wheeled sidecar stays planted better then one with a light wheel. And how heavy you are makes a big difference. There is a "rule of thumb" is that the sidecar should be 1/3 the weight of the bike. I wish this "rule of thumb" would go away as is is wrong.

Jay G
DMC sidecars

866-638-1793

Hours Monday - Thursday 6-4:30

www.dmcsidecars.com

Another thing that makes a difference, at least to my way of thinking- are you very familiar with the rig. That is, is it an extension of yourself when riding, or is it somewhat a stranger to you? I prefer to ride either of mine with no ballast if Petey isn't along. Familiar rigs on familiar roads. Familiar rigs on less than familiar roads, I'd either use a couple old milk jugs filled with water that can be pitched or ride much less aggressively.

I like the 5 gal. collapsible water jug but mostly leave it empty when no passenger. I don't tend to ride to aggressively these days anyway.

I usually put a 50 pound bag of sand behind the seat of the sidecar, I think it's better to have too much ballast than too little.

Doyne

I have been riding with the car for about 8 years and at this point, I do pretty well for an old guy.  Can not raise the car when standing on the floorboard.

I think I will also try the 50 lb idea.  I saw where there were some plastic-type jugs that can be filled with sand on Amazon.  I also like the spare gas idea.

Have to put my brain to work.

Thanks everyone for the suggestions.

Bill 

Everyone has to make decisions for themselves but...

In the long run it's probably better to weight the sidecar permanently (if it's required).  The left peg test works pretty well and takes into account the driver and car weight variables.  It really won't take all that long to learn to ride within your limits.  In fact I think it will take about as long to get fed up with dealing with ballast.  

I started with ballast and didn't know that I could do without it until, while on a ride, I realized that things were going fine and I had forgotten to add the ballast.  It's good to practice but don't take chances until you're confident in your abilities and your rig.

Bill, you can keep guessing, listen to advice from strangers based on anecdotical evidence, or employ proven science (physics) to precompute with a tremendous degree of accuracy - that's up to you.

Just define, how much resilience against lifting of the side wheel you want in right turns. This is measured in the unit "g", or fractions thereof, as can be read from my interactive 3D sidecar simulator. If you need any help in translation, just let me know.

On that occasion: do you know how much resilience against tipping over in right turns your rig currently has, without having added any weight?

Have you thought about how you would recognize a "good enough" state? My advice: think about both questions and start from there.

ChrisK,

You too are a stranger to most of us.  You broke upon the forum positioning yourself as an expert.  We welcome that, technical articles are thin on the ground here.  We do ask you to be respectful toward input from others.  Many, probably most, of our members speak from personal experience and admittedly "seat of the pants" observation.  That doesn't mean that they shouldn't share their opinions and experience, all posters who stay on subject and act in a civil manner are welcome here.

A.

Al,

thanks for your open feedback, which I appreciate very much.

I am an engineer, and as such, am geared towards maximum efficiency. Which means, that I generally employ a classical engineering approach:

• Know where you are
• know, where you want to be
• decide, how you want to cover the distance between the two.

As such, I'm aware that I'm very straightforward. Which means, that folks might take offence in my maximally direct approach. Which is not my intention at all.

Diplomacy is not one of my strengths.

When someone posts a technical problem, I apply the best of my knowledge to help out. This involves, that I suggest the shortest path to the best possible solution, from my engineering point of view. In such a situation, the feelings of other participants in the given situation only distract from the shortest path to this optimal solution. So I consider them secondary.

If this approach is not welcome here, then I will respectfully retreat and leave you alone. At 63 years of age, you don't switch your personality anymore.

I'm willing to subject myself to a public vote of the "like" vs. "dislike" kind of thing, based on this very post. If, after a period your choosing, the majority would prefer me to stay away, so be it. Else, I'll stay with you the way I am.

So, Al, please decide on the deadline, and I will comply.

Best regards,

Chris

Chris,

We don't "vote people off" and we don't trash other people's ideas.  You are welcome here and I believe that most of us found your input interesting whether we agree with it or not.  All we ask is that you be civil and respect the idea that everyone is allowed to have an opinion.  Some of them are based on physics and some are based on experience.  All of them are deserving of consideration.  We in a "sticky post" near the top of this section we talk about the responsibility of the reader.  Here's the text so no one has to go looking...

Information about sidecars is tough to find. One of the great things about this site is the depth and scope of technical information that is available here. One of the terrible things about this site is fact that we don’t vet the technical information that is available here. What did he say?

We are a very open environment and we let “almost” anyone post here so long as the subject is sidecars [even in some tangential way]. Because of our specialized subject matter, lots of folks come here to ask questions and that’s a huge part of this site’s reason for being. Because of our open nature, anyone can reply to these questions…even if they don’t know what they are talking about.

It is the responsibility of the reader to sort the wheat for the chaff as it were. PLEASE, read with at least a slightly skeptical attitude. If you see six posters that basically agree on a subject and one that is off in the ozone, factor that in when considering who to believe. If you want to do a little more checking, you can click on the poster’s name [handle here] and see how long he’s been on the site and maybe look up some of his old posts. If you see a poster who is giving you advice and then find that he has been on the site for a month and when he first came on he was asking the same questions that you are asking or if he openly admits that he paid no attention to the advice of others… well, you get the idea. DON’T PAY ATTENTION TO IDIOTS!

You have a responsibility to critically evaluate all the information that you read here and make your own decisions, good or bad.

If a reader here likes your ideas they will follow you and if they find that your information is believable and applies to them they will give you positive reinforcement.  If you treat them badly by talking down to them, they won't value your ideas, even if they are valid.  There's no reason to take a personal swat at anyone or any group nor is there a reason to belittle their ideas.  Saying that you don't agree is perfectly ok, that's part of how we work things out.  I looked at your article and thought it was interesting.  I didn't go into much depth but it didn't seem to address "live loads" and how they shift during a turn.  It might be there and is addressed but I didn't see it right away so I moved on.  I didn't challenge you, I'd probably lose.  But that's not why I didn't challenge you. I appreciate ANYONE who adds technical content to the forum.

As I said at the first, you are welcome here.  If you are abrupt...well. so am I but I try to be civil.  We'd like you to stay but if you feel that you must leave that's up to you.  Personally, I hope you stay and I hope you respect the ideas of others, even if you don't agree with them.

On a personal note, I've been working on this website for many years and I want to retire from that responsibility.  Soon someone will be found who will replace me.  When that happens, they will steer the tone of the forum.  Stick around, I won't be here too much longer.

A.

Chris, In some ways, it's too bad you came onboard when covid has taken over so much of our lives. When rallies and events have been cancelled. If you had the opportunity to join in a few group activities and hang out with a large group of sidecar enthusiasts to experience the friendship that is so apparent at such events, you'd get the idea, I think, of what Al is saying. Nobody lets their ego get in the way of sharing opinions. It's that genuine friendship between people with all sorts of varied backgrounds with a common interest in sidecars. At most of these gatherings, it seems that there are more people who are looking back on being 63 than are looking forward to it. But it's a topic I've never heard brought up. The conversation comes easy as does the feeling that one is among friends.

Al, thanks for what you do. I appreciate the effort you and all those who keep this group firing on all cylinders put into making it happen. I'd personally be happy to hand the WA State rep job over to anyone who raised their hand as well. And it's much less demanding than what you do. OK. 'nuff said.

Here's hoping everyone has a good Thanksgiving in spite of covid demands. And here's to a much better, more normal 2021!!

Well, Chris, it looks like perhaps coming to any sidecar rallies stateside might be less likely than I'd hoped. Looking at your profile it appears you're in Germany. One would never guess that based on your command of the English language.