David: As you can see, there is no single answer to the shimmy problem. Personally, I think where the load is, both front / rear and high / low) and how each of us rides are major factors. A good example is Joe Bartoe's experience with shimmy on his Hilsen with a light front load, whereas my Atlantis will shimmy with a lightly loaded rear saddlebag but moving that bag to the front solves the problem. Atlantis & Homer are different bikes, and Joe & I are different sizes and likely riding styles.
As to solving the puzzle, I found a gentle hill that allowed the bike roll up to about 20 mph w/o pedaling (pedaling seems to dampen things for me). I took 4 panniers loaded with books to simulate the weight of my gear, and tried all front, all rear, some front, some rear, etc., until I found a combination that was rock solid. What works for me is 60% of the weight in front & 40% rear. For an S240 or a loding tour, I only need 2 bags so they both go on the front. In the photo, I don't recall what was in the saddle bag but it was probably a last minute add for overflow, and the sleeping pad hanging off the back can't weight much. To avoid buying new stuff for only a few trips per year, take what you've got & find a similar hill and experiment. I think the no-hands is asking a lot but I grant you should be able to ride the bike light handed & not in a death grep. Seriously try putting some heavy stuff in the basket BUT make sure it can't shift or bounce around. I had some dive weights in my Acorn bag on time (they would let us drive tent stakes) and got shimmy for shimmy (probably had 12 lbs of lead). Location is another variable. Weight up high (basket, rando bag, etc.) seems to be shimmy enabling. If you can't come up with a non-shimmy combination with your existing rackage, you may have to look at low riders. IMHO getting the weight centered around the front axle seems to improve life greatly. I've used my big Ortleibs on my Tubus Duo front rack and it's rock solid. Another consideration that's been mentioned is the roller bearing headset that Riv sells. I've got one on my Atlantis and have not had any shimmy since installing. But then before that I'd worked around the shimmy with loading so it can't be credited entirely. But it's still worth a thought. Lastly, and probably heresay here, but I've had situations where I know the Nitto Big Back rack was contributing to handling difficulties, albeit likely overloaded by their standards. As beautiful as they are, they lack lateral triangulation and can develop resonance. Tubus and other rack makers design with a triangle, viewed from the rear, that greatly stiffens the structure. The Nitto R-26 (?) that I had for while is essentially a pyramid, is made out of 10 mm tubing, and is as stiff as they come. Unfortunately the platform was a little small for my needs. On our next S24O, I'll throw all my junk on the back to see how things work with Tubus rack since I got the needle bearing headset. The downside to front low riders is limited clearance. dougP On Thursday, May 28, 2015 at 9:27:05 PM UTC-7, cyclot...@gmail.com wrote: > > It took me a sec to find a photo, but it handled just as terribly when > it was straight rear-loaded with nothing on front. You can see it on > the right in this photo, with both panniers in place and packed full: > https://www.flickr.com/photos/cyclotourist/15187812094 > So basically two panniers full + tent in back = bad > One pannier + tent in back with light load on front = bad > Is there a magic way to load this that makes it pleasant to ride? I > know it's not a loaded touring bike, but hoping for at least a little > stability whilst loaded and not crazy shimmy all over the road. > > On Thu, May 28, 2015 at 9:11 PM, Joe Bartoe <jba...@hotmail.com > <javascript:>> wrote: > > David, > > > > My experience with a Hilsen with small front rack and small front bag on > it, > > indicates that Riv-designed bikes are not really good handlers with > front > > loads. It shimmied like crazy! The other items may have contributed, but > my > > guess is the stuff on the front had more to do with the shimmy. > > > > Joe > > > > Joe Bartoe > > Synaptic Cycles Bicycle Rentals, Inc. > > email: j...@synapticcycles.com <javascript:> > > website: www.synapticcycles.com > > Twitter: @synapticcycles > > phone: 949-374-6079 > > > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "RBW Owners Bunch" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to rbw-owners-bun...@googlegroups.com <javascript:>. > > To post to this group, send email to rbw-owne...@googlegroups.com > <javascript:>. > > Visit this group at http://groups.google.com/group/rbw-owners-bunch. > > For more options, visit https://groups.google.com/d/optout. > > > > -- > Cheers, > David > > Member, Supreme Council of Cyberspace > > "it isn't a contest. Just enjoy the ride." - Seth Vidal > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To unsubscribe from this group and stop receiving emails from it, send an email to rbw-owners-bunch+unsubscr...@googlegroups.com. To post to this group, send email to rbw-owners-bunch@googlegroups.com. Visit this group at http://groups.google.com/group/rbw-owners-bunch. For more options, visit https://groups.google.com/d/optout.
