It’s that time of year again in New England. The snow is melting, there are brief moments of riding in the warm sun, and my cross bike feels super slow rumbling along the grimy shoulder of the road. It’s time to break out the road bike and, luckily for me, time to build a new frame.
I work at PARLEE Cycles in Beverly Ma, where we focus on building light, stiff and comfortable carbon fiber road frame sets. The most striking quality of PARLEE frames is their very minimalist appearance. This can give the mistaken impression that they are simple bikes. The truth is that all of our tube sets are designed for performance first and aesthetics second. We have a huge array of tubing options, geometry and finishes that can give someone a truly customized bike. So, what do I really want out of my new frame? That’s the question.
My last bike was great, I loved the way it fit, felt, and handled. But, it was kind of heavy. 16.5 lbs. for a 62cm bike isn’t bad, but it isn’t lithe either. On the other hand neither am I at 210 lbs. and 6’5”, so that needs to be taken into consideration. That said I want to drop a pound on the bike. I also want the bike to snap more out of the saddle. My old bike felt a little flabby in torsion at the bottom bracket. At odds with my desire for a more responsive ride is that I need the bike to be really smooth like the bike I have now.
The first advantage I have with regard to weight reduction is the method of construction PARLEE employs in joining the tubes of the frame. The frame’s tube junctions are molded together rather than assembling the frame with glue and pre-made lugs. The net result is a mechanically superior tube junction because of its tremendous strength to weight ratio. Generally PARLEE’s construction method reduces weight by 120 grams when compared to the aforementioned method of building carbon frames.
There are other things that can be done to control the weight without sacrificing ride quality. I have decided to use a PressFit 30 bottom bracket. The PressFit system from SRAM, or the BB30 standard first introduced by Cannondale, allows the crank, bottom bracket, and frame to be lighter and stiffer than a comparable English bottom bracket and crank. This is because since the crank spindle, and bottom bracket shell of the frame are oversized, the structure of these parts can be thinner and more lightweight while being tremendously stiff in terms of torsion.
Another weight-saving feature of my new frame will be the integrated seat post. This avoids redundant material in the seat post/seat tube interface found on a standard frame. I plan to use a Ritchey Super Logic carbon ISP head, which weighs about 100 grams. This part is sturdy enough to support me without complaint while being fairly light. An added benefit of the ISP is that I can select the type of tube I want. The tube I will use for my ISP is designed to be compliant. Typically we use compliant tubes for more lightweight individuals or for bicycles that will be ridden on rough surfaces. In this application the ISP will absorb impacts from the road because it is designed to be flexible.
The rest of the tubes (top tube, down tube, chain stays and seat stays) are all fairly typical for a rider of my weight. This will make a frame that has stiffness in torsion while being comfortable. In other words, the frame will resist the loading from rider without feeling harsh. I will also use an Enve, 1.0, 43 rake fork, which is light and will be a little flexible under input from the road. I chose to go with a seat stay wishbone because its stiffness will compliment the ride quality I’m looking for. It will also give the frame great braking performance in the rear.
To summarize: the tube set has been selected for its ability to deliver efficient forward movement while the fork and ISP are giving the frame a more comfortable ride.
From a geometry perspective, my frame will be tried and true with 73 degree seat and head angles coupled with a 7.5 cm drop that will give me an agile feel at the bar without requiring too much attention. The chain stays are going to be a relatively short 403 mm, which keeps the wheelbase nice and tight. This equates to rear end snap and will allow for the rear wheel to follow right behind the front giving the bike a feeling of being on rails when cornering.
I still have some of the final details to work out, and I’m not sure what components I’m going to use or, more importantly, how I’m going to have it painted. I do, however, have enough figured out to make a draft and begin building, and I think it’s funny that the paint job is the most difficult thing for me to decide on. Maybe that’s because it is an aesthetic decision, and therefore harder to make. The important thing is that I know exactly how I want my new bike to ride, and I have a pretty solid plan on how to get there.
The next segment will cover the method of construction, the equipment employed to do the job, and the specific considerations that relate to which components I will use to build the frame up. There are also some non-standard items that I have been working on that need to be tested before the bike is finished. Now I’m really excited and I can’t wait to start building.