René, Your experiment is remarkable. As a scientist I admire your desire to experiment and learn, It also prompts me to write my first ever response to the Group. I have lurked in the background vicariously enjoying passionate debates about front bags vs rear bags, clips vs open petals, light responsive tires vs heavy stout "German" tires... you get the point. I enjoy the discussions and the passion. I have learned a great deal. Your involved experiment makes me ask why? The analogy is strained, but if I wanted my Subaru to handle like a Porsche, I could try to modify my Subaru to handle like a Porsche, or get a Porsche. In your first sentence you mention my two favorite (living) sources of bike wisdom. I admire and respect both, as it seems you do. The Riv cachet is powerful, but it doesn't suit all, nor does it try. At some point you might want to say "I like Riv bikes, but prefer the handling of...". As for me, I prefer my Subaru. Best of luck in your search.
On Tue, Jun 5, 2012 at 4:37 PM, René Sterental <orthie...@gmail.com> wrote: > Disclaimer: > > This is a very long post and I want to start by stating that I don't mean > to start another heated debate on high vs. low trail fork, or Jan vs. Grant > philosophies, etc. I just want to describe this experiment and its initial > results to the group so anyone thinking along the same lines has another > point of reference. I'll gladly answer any questions that are posted, > either privately or publicly but let's handle it as the controversial topic > it usually is. Also worth noting is that this is a modification I chose to > do on my own to my bikes and while Rivendell certainly supports the > exchange of information and knowledge about bikes, they certainly stand > proudly by their bikes and their design philosophy. This post is in no way > an attempt to challenge that. They are aware of my experiment. > > Ok, here I go... > > For a number of reasons that I can just summarize, in no particular order, > as the tendency of my Rivendell bikes to shimmy with any loads (especially > my Atlantis), my dislike for how they handle with any front loads > and especially heavier ones, as well as with heavy rear loads, all of which > magnify the tendency of the front steering to pull and require > overcorrection when turning, as well as the interesting and very educating > online discussions and articles on bike geometry and fork geometry and its > effects on the handling characteristics of a bike, I decided to try it to > see for myself what the whole low trail geometry claims were about. > I wasn't able or willing to go buy a new bike just to experiment, and > even if I did, there would be no way I could tell what the low trail fork > would do to the handling of my Rivendell bikes which, aside from the > nuances/issues stated above, I love. And yes, while I could > certainly adjust to all of these quirks, I just didn't like having them on > my bikes. The obvious solution recommended by some people on this group in > addition to several articles online pointed me to Tom Matchak in the East > Coast who had already built low trail forks for other Rivendell bikes. Tom > seemed to have a great reputation as a builder and immediately knew what > this was all about when I contacted him. Due to the long lead time to have > the low trail fork built for my Atlantis as was my original intention plus > a few additional considerations that came up as part of this process, like > the need to have the Atlantis repainted and why not, the Hunqapillar as > well (never did like that gray color much), I decided to take the risk of > ordering two low trail forks for both the Atlantis and the Hunqapillar as > these are the bikes I mainly ride loaded. > > I asked Jan Heine for his low trail recommendation as well as Tom Matchak > and they both came out with the same number: 40mm of trail, which requires > a rake of 70mm for 40/50 mm tires. On the Hunqapillar, the same 70mm rake > comes out to 42mm of trail. For comparison, the standard Rivendell fork for > the Atlantis has 45mm rake/65mm trail and the standard Hunqapillar fork has > 50mm rake/63mm trail. I had to send several detailed measurements to Tom > Matchak so he could preserve the crown race to axle distances on both > bikes. He also specked cable guides for my dynamo lights as well as fender > attachments so I no longer need to fiddle with the darumas to mount the > front fenders and can screw in the fender directly to the underside of the > crown. Additionally, the fork for the Hunqapillar was spec'd with a Pacenti > MTB bi-plate crown to run the 50mm tires with 60 mm fenders and the fork > for the Altantis with a Long Shen A16 crown to be used with 40mm tires and > 50 mm fenders. Regretfully but understandably so, I got a negative response > to my inquire at RBW on whether I could buy a pair of Rivendell crowns for > this project, so while none of these crowns is as beautiful as the original > Riv crowns, they're sort of Rivish, especially the A16. Both forks were > also spec'd with the usual set braze-ons for the normal array of racks > including the Nova and Duo Lowrider racks. Tom put these braze-ons on the > front of the fork instead of on the back where the Riv forks have them with > the effect that it will be easier to level them properly. I didn't ask for > the braze-ons on top of the crown as I have no use for them. > > After the long expected wait (this whole project started in december of > 2011 and it took until febrary for the orders and details for both forks to > be completed. Tom was going to schedule them to be built in March anyway > and was done in April. He shipped both forks to the local painter Keven > recommended (D&D cycles); for some reason I never understood, he refused > from the start to ship the unpainted forks to me, but agreed to ship them > to the painter of my choice since the bikes were going to be repainted and > the forks would have to be painted to match the frames. > > The second phase of this project is for me to disassemble the Atlantis > first and take it to Rick to be repainted. This repaint was necessary (as > these things are) since I had the right down tube braze-on replaced after > almost destroying it during the original build (another long story). Not > wanting to be without both the Hunqapillar and the Atlantis at the same > time, I asked Rick if he could give me the Hunqapillar fork to use while > the Atlantis got repainted including the new fork (4 - 6 weeks waiting > time) and when I took possession of the Atlantis, I'd drop the Hunqapillar > so he could repaint it to change the stock gray color. He gave the new low > trail fork for the Hunqapillar its primer coat and a quick coat of > Hunqapillar gray so it wouldn't look bad as I rode it and tested it before > the repaint. > > I had such a hectic travel and work schedule that I just didn't have the > time to disassemble the bikes to take them to Rick's shop to be painted, so > it wasn't until this past Friday, a bit over a month after the forks were > delivered, that I was able to pick up the Hunqapillar fork. On Friday > afternoon I removed the Hunqapillar's stock fork, took both to my LBS to > have them swap the crown race from the stock fork to the new fork and > proceeded to install the new fork. I'm thinking of getting those tools to > do that myself, although it's such a low frequency job that I normally have > the mechanics at the LBS do it, but it's always a hassle. Anyway, that > night I finished the installation and put back the Pass & Stow front rack I > had before and decided to put the Swift Industries Pelican Porteur bag I > had ordered when I first ordered that rack. On the standard Hunqapillar > fork, I hated how the bike handled with the Pelican Porteur bag on the > rack; the empty Pass & Stow rack wasn't bad on the handling of the bike, > but loaded with the bag it was awful. It pulled so much on the bars, > especially when taking turns that while I could adapt to it, like I had > done on last year's S24O to Mt. Diablo, I just didn't like how it handled > and wanted to do a direct comparison. I didn't load it too much, just my > Fuji X100 camera and a sweater, but the bag itself is kind of heavy with > its dual canvas exterior/plastic interior and padding. It has the > extra-heavy black canvas that they offer as an additional option. I also > put inside a padded F-Stop insert which I discovered recently as a great > solution for carrying camera and lenses on the bike. > > On Saturday morning I did a 15 mile mixed terrain ride (though mostly on > twisty paved trails with lots of people running and walking around as well > to see how the bike would handle with the new fork and boy, was that a > revelation! The Hunqapillar's handling is, in my opinion, vastly improved. > I was afraid it was going to be squirmy or squirrely, but to my surprise, > none of the good traits were changed but all the less desirable ones are > gone. I don't know if I can verbally describe how it feels accurately, but > where before I had to "drive" the bike, especially around turns, now all I > have to do is think of where I want to go and the bike just responds > effortlessly. Turns are beautiful, whether at low or high speed, yet the > bike tracks perfectly and no longer wants to wander or pull on the > handlebars. The front load dissapeared while riding and I could zig-zag > around people so smoothly it was a pleasure. Riding on singletrack was > awesome. > > Needless to say, I'll have to do further testing with different types of > loads and racks, front and rear loads, rear only loads and no loads. This > morning I rode my bike/train commute with a bit more on the Pelican bag and > it was still very nice. Between the new low trail fork and the Bosco bars, > my Hunqapillar is now perfect for me. Perfect fit, perfect comfort, all the > hand positions I need, the handling I wanted. Next will be deciding what > color to paint it, although I'm leaning towards silver now. I cannot really > ride my bikes no-handed, but if anything, it would seem to me that with the > low trail fork, as expected, it's a bit more difficult for me to ride > no-handed. Further testing/practice needed to confirm. > > Here are the initial comparison photos on a side by side montage to > appreciate the suble differences between the stock high trail fork and the > new low trail fork, especially the rake. *http://tinyurl.com/7phz5kz* > The photo of the stock fork was taken during the original conversations > with Tom and I used my iPhone in my office. The photo of the new fork was > taken today with my X100 and its quality is better. Obviously the > perspective on both is not equal. I can add close-ups of the stock fork > next to the low trail fork if requested. > > René > > -- > You received this message because you are subscribed to the Google Groups > "RBW Owners Bunch" group. > To post to this group, send email to rbw-owners-bunch@googlegroups.com. > To unsubscribe from this group, send email to > rbw-owners-bunch+unsubscr...@googlegroups.com. > For more options, visit this group at > http://groups.google.com/group/rbw-owners-bunch?hl=en. > -- You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bunch@googlegroups.com. To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.
