From my experience of building a high handlebar chopper, I learned the value of giant rear tire / skinny front tire.
The problem, I discovered, is that the eye perceives the skinny tire as having a smaller diameter, compared to the fat tire. Optical illusion, and not the way I want it.
I could visualize a solution. However it would take me years to find a good lightweight cantilever cruiser frame with which to make this.
I finally ran across a 2000 Jamis Earth Cruiser. It has the small bottom bracket, so I could put in any racing crankset, it has a 1-1/8” head tube, so I could select from a wide range of high performance forks, and It takes the standard 27.2 seatpost. Along with other high end details, this classic beach cruiser frame is aluminum – super trick.
To alleviate the fat tire / thin tire wheel illusion, I needed to go with a large diameter front. Harley Davidson Sportster style. The Harley folks worked out this design problem some time ago.
I worked out the variations of riding geometry changes from the wheel size differences over the range of 27” front to 24″ rear; brake problems, crank arm conflicts, bottom bracket height, etc. Then, balancing cornering clearance with a pretty good lazy steering angle, I settled on the 26” fat rear and 700c thin front. This would only require a fork change. Well, and all the other stuff connected to the fork.
I searched out a 700c length threadless fork with brake posts for the cantilever brakes. I removed the clunky steel headset bearings and put in a sleek sealed aluminum Cane Creek S2 headset. I found a good high flange, low rim, 700c front wheel from a Bianchi Pista. And picked out a short Bontrager threadless stem.
I had to rig up a cable hanger for the brakes; I got it pretty well with a piece from another headset and a barrel cable adjuster from a donor brake lever. I kept the old school cantilever brakes so that I could keep matching brake levers, though these levers do have a switch inside to use newer linear pull brakes.
Researching for the rear I discovered a super light, Kevlar beaded, gigantic stunt tire: 26×2.1 KHE MAC2 made in Germany http://www.khebikes.com/2012/mac-folding-tires-p-1231.html. Wow, great tire, unusually good combination of performance. Then the front got a 700×23 racing tire wrapped around a wheel from a Bianchi Pista. That Bianchi solid high flange hub aesthetically matching the big Nexus hub quite well.
Only slightly heavier than the derailleur system, but much nicer, that 7 speed Shimano Nexus IGH internal gear hub really makes this a versatile bicycle. You can ride a variety of terrain, slow speed cruising and high speed flying, plus go reasonably long distances. The roller brake is a heavy thing however, but with no other mounts on the frame, it’s that or a coaster brake.
Super grippy VP-001 pedals rock!
On the street it is comfortable and quick. Overall the damn thing is surprisingly light. It is a blast to ride, it is super stylie plus high performance = well balanced.
Rockin’ design! Traditional plus modern. Looks fast and fun.
Jane understands
I’m building a frame like that Fixed gear on 700c with drop bars just got the frame in from powder coating today can’t wait!! Nice Bike.
Whoa, you are building a classic cantilever frame as a fixed gear?! Wow, dope! Rock on. Keep me posted.
I really like what you’ve done here! Looks fantastic! I’m still not a fan of fat rear tires, but you know more about that than I do. Congratulations on a home run with this bike — out of the park, my friend!
Hey Thanks George,
Great compliment. The fat rear tires on my street bikes with front suspension are really thin front tires (rears are normal size). The function of the super fat tire on this cruiser is a type of suspension; and I guess, a fulfillment of a chopper tradition.
Glad you like!
===Brian