Hi Folks, I've been searching the net for parts/methods in my endeavor to hang a Dnepr on my '78 R80/7. I came across Perry's Sidecars in Ft. Worth, TX. I called him about modded triple trees, but he told me he sells an entire mounting kit including the trees for a very reasonable price. He sounded like a very knowledgeable gent and a nice guy to boot. I asked about a subframe and he was very adamant that his system does away for the need for one. That's contrary to everything I've heard elsewhere. He tried to explain it to me, but I can't quite envision it and he doesn't have detail pics on his site. Has anyone out there used Perry's kit to hang a chair on their /6 or /7 airhead? Is it stiff enough with no subframe? How was the rest of it- triple trees, etc? I'd rather fork over the dough to Mr. Perry than be cutting up and welding mill steel in my basement, not to mention engineering it all from scratch. Any comments are appreciated. Photos of a Perry system would be great! Jim
Jim, Ask Perry to send along a few pictures. No subframe doesn't seem like the usual way to approach this problem, but you can't judge the results without any facts. Pictures will clear up a lot of questions. After we see Perry's sytem we can nit pick or cheer as seems appropriate. Sidecar Oscar
Perry has a good reputation and has been doing sidecars for a long time. However, we used a mounting kit I believe came from Perry on an old /5. It was a solid mount, but the lack of a subframe was apparent. I could actually see Mike's bike flex and step through the corners. I know others who also claim a subframe isn't necessary for the old airheads, but I remain unconvinced...
There's not a triangle to be found in the airhead loop frames. They flex too much by themselves. I've not tried to hang a car off of one but I've owned several airheads and they have way too good of a reputation for as whippy as they are. Though unexperienced, I'm unconvinced as well. I could actually see Mike's bike flex and step through the corners. I know others who also claim a subframe isn't necessary for the old airheads, but I remain unconvinced...
From the /5 up the BMWs really should have a subframe or at a bare minimum a partial subframe. Yes, many will say " I ran a slash whatever for a hundred years with no problems blah blah". Some will report of flexing going on. Some have actually had the motocycle frame crack. QUESTION: How precious is your cargo? Ever hear the term 'rubber cow'? Subframes add strength but also allow mounting points to be placed for decent triagulation and ease of adjustment. We mount vary few sidecars without the use of a subframe. Your call of course.
BMW /6-/7 mount assembly. Actually the front mount has been changed slightly at the top but you get the idea. We've done a lot of these. B
Same here, I don't get the idea. Got any photos of one installed? Thanks, Pam, who'd also like to know why the web site doesn't have photos, you guys must spend hours on the phone
Yes we do spend hours on the phone. LOL The problem when you are a manufacturer in business to hopefully one day make some money you are torn between what you do and don't do about pictures. The problem from a business point of view is that you spend time and money designing parts that others may not have. If you post too many pictures what you have spent time doing is now copied from the pictures and then offered at lower prices by companies with lower overhead, labor and material costs. Kind of a rock and a hard place scenario. Besides, talking to potential customers keeps us out of trouble. Here's a shot of the front shown on a /5 that we are mostly using on the /6/7's now. A little different than the one shown in the first picture. B
Thanks, Sparrow. It seems to me that moving the mounts several inches from the frame would make things weaker (lever principle), not stronger, even if there are more frame attachment points via the "subframe," which, btw, I don't think is a subframe at all, more of a frame support here and there. Perhaps this is good and appropriate, just the support the older airheads need and no more? I'm not a metal worker, just speaking as someone who usually recognizes strong and weak connections. Maybe there's some advantage to not welding the actual frame? As for business practices, speaking as someone who cofounded and ran a software development firm for 24 years, if you can't show it in advance you usually can't sell it. So protect your intellectual property and then get on with it, but please spare me the excuses. And while there are plenty of build threads here, I suspect, based on the number of people who go to Claude and/or DMC, they're a fairly low percentage of the audience; so it's unlikely they'd steal ideas. :) Pam
Pam, I think you may be being a little naive regarding stealing designs. A number of threads here have been quite frank about wanting photos of mounts for just that purpose. Agreed, photos of the products are a necessary sales tool, but detailed photos showing the attachment isn't necessarily a requirement or even a good idea. Of course you are correct; not everyone desires or has the time or skills to fabricate their own mounts and those that think they do often end up wishing they had bought a mount kit from an established builder. Regarding the subframe in question. It is certainly an improvement over "universal mounts". Welding directly to the frame is usually not a good idea, but if you have the skill and don't mind permanently modifying your bike, is another approach. As I recall, Mike ended up adding a good deal of re-enforcement to his airhead frame, including removing the battery to the sidecar and adding a cross frame brace through the former battery box and diagonals fore and aft above the jugs. You can see similar bracing on period racing BMW frames if you search. Although simply bringing the mount attachments across both sides of the frame may be enough, BMW frames are weak and flexible and not intended for the lateral loads of a sidecar. Additional cross bracing an shoring up the rear frame to main bike frame such as Mike did is not a bad idea.
I owned a /6 whose frame was broken in more than one location by an attached Ural. After the broken frame was repaired, a sub-frame was installed to strengthen the mounts. The main frame of 1969-95 twins is thin walled tubing, and will flex laterally even with no sidecar attached.
OK, first, you don't run a software development business for 24 years by being naive about what people will try to steal; and in the case of one application, an accounting system, we shipped open access to the code. So what you do is protect your property rights. Also, you must assess the abilities of your buyers/stealers. I also published a magazine about a software system, not ours, for a couple of years; and no question, people stole it, even password protected. But we didn't answer questions posed by people not on our subscriber list. The fact is, the thieves weren't going to buy our rag at the price we were charging; but at least they couldn't sue us for bad advice. Second, perhaps a year of use is too short to reveal frame problems; but fact is, my R90S with sidecar performed very well, no frame problems to date. That's a fact, whether it suits other experiences or not. Now clearly I'm thinking about this, giving technological advances their due; but I don't see how you can make all sorts of excuses for your KLR frame failures (Took what, a month to break?) and then claim the BMW /5/6/7 frames are weak. Compared to what? What effect does tub weight have on frames? How about mounting arrangement? Mounting components? Etc.? No, just a blanket statement that directly contradicts my personal experience. I happen to have a lot of respect for what you do and how you do it, please keep up the good work. Pam
Pam Regarding your comments on my earlier post. If you knew me better you would know I don't make excuses, I only tell it like it is. Anything I tell you or anyone else is the fact as far as I know it. What I told you about the picture posting was a fact not an excuse. You asked a question and I answered it for you with the facts and even posted the pictures that were asked for. All that got me for my trouble was more criticism. Not a thank you for the answer and pictures, just an accusation of excuses and why you thought the mounts were not right. Frankly, I didn't answer your response right away because at that point I would have probably not been too polite myself and I didn't want to lower myself to that level. The mounts shown in the pictures have been used without problems for about 15yrs now. I would say we sell about three or four sets every month. The only problems we had at the start were due to tooling off of a bike we didn't know was not exactly straight so there were some fitment issues. Once we figured out the problem we got another bike in to tool off of. One thing I have learned in the last 40 yrs playing with sidecars is that there are many ways of doing the same thing and they mostly all work to some degree. This is what works for us. I believe that if you were ever to go for a ride with ReMenace you would gain a new respect for the fact that his rigs manage to stay together at all. I don't know anyone that rides their rigs harder or any that spend as much time in the air. He is the ultimate test pilot to see how strong things are and the average street rig would fall apart trying to follow where he goes. Again, just my opinion, but I think we would all gain a lot more from discussing our ideas and comparing the pro's and con's of whatever subject we are talking about than criticizing each other for not doing things our way. Barry
Barry - well said! I at first couldn't understand why I had such a tough time finding pix of mounts for my GL1100... I mean, aside from maybe old airhead BMWs, in their day they were probably the most popular hack'd bike around! I had Side Effects in Kamloops fab me mounts... am almost reluctant to show pix now knowing how proprietary designs are!
Hi Pam! I am glad your R90 rig has worked well for you, but I still would not build one without a subframe. BMW airhead frames are flimsy and flexible compared to older /2 frames. You are right, I have broken some KLR frames. I wouldn't recommend mounting a sidecar to a KLR without a subframe either. While I think my frame failures were probably due to extreme use and subframes that needed a bit more development, it did take longer than a month for me to break them(not sure where you got that). I don't have a high opinion of KLR build quality, but they are cheap enough to experiment with and fun to ride I suspect the market for software may be different enough from niche manufacturing such as sidecar mounting to make your comparison questionable, but since I am not in either business I am just guessing and could easily be mistaken.
Barry, I'm trying real hard to do just that. I know that RedMenace's KLR rigs take a lot of heat; and I wasn't being absolutely critical of his rigs, only relatively in the context of criticizing my BMW rig. Or, more to the point, of seemingly disregarding completely my experience with said rig. See, polite discourse at least allows for the possibility that my rig was a very good one. Also, I said that it was possible that your "subframe" for old BMWs might be exactly what they needed if their frames failed, and not the $2,000+ overkill that I see here day after day. I readily admit that the new, almost frameless BMWs, need such "overkill." And the fact that I reiterated someone else's request for better photos meant that I was considering DMC's solution if/when I hang another sidecar on my ancient Beemer. About the last thing I'd want to do is endanger life and limb by trying to build something myself, plus I don't much like working metal. All that other stuff just got in the way; so I was trying to tell you how I got it out of the way for my business. And now I'm really irritated that I apparently find it necessary to explain myself. Pam
Fooling around with sidecars is so small a niche that I would guess 90% of rigs are put together by some local guy with a welder and a few pictures. The gas cost and hours spent driving my truck and parts up to the nearest real sidecar shop is greater than the total cost and time I have in building the bracketry myself. To me, putting together myself is a major part of the attraction. My next build will be a Harley with a "Woody" hack. It's just a matter of time and $.
Amidst some of the uptighted-ness I gleaned enough useful info to decide that I will go the subframe route. Underway, in fact. It will be home-made. I think the thread got off-topic from my initial question about whether Perry's was a good source for mounts, but it sure was a spirited read! Thanks folks!
