Ryan_M

I have a Giant Roam 1 that pretty much had all of it's parts upgraded with some going to benefit the GFs bike. The only original part left was the frame and some odd small bits. So I decided to order up a frame to have a full on 'built by me' ride - with the intention of taking the left over parts to build a bike to sell. I recently got it finished and all the kinks ironed out so here it is!

It's a 29"er chinese carbon MTB frame but with a carbon fork meant for a 27.5". I took the Roam's geometry and put it into CAD and compared that with the dimensions of the chinese parts to come up with this combo. I wanted a little lower and a bit more agressive geometry, aiming more for a gravel bike type ride. I haven't yet taken mesurements for the geometry of the final as-built product but so far I'm happy with how it feels though I don't have a lot of miles on it yet. It has carbon seat post, stem, handle bars, horns, and bottle cages to continue the theme.

Drive train is nearly full Shimano 2x11 M8000 including M8100 pedals. I now run 38-26 rings. The only odd one out is I'm using a HG800-11 11-34t cassette. I'm really liking this setup a lot over the 38-28t rings and 11-42t XT cassette I originally had since I get closer ratios between the gears which I really appreciate, and I only had to give up my one lowest gear to get it. The brakes are M6000 with J03a pads and RT66 rotors. The heatsinks on the pads are likely unneccesary but they were only $7 extra at the time of ordering so why not for the extra bling lol.

The wheels I built myself and are DT swiss 240 straight pull 28 spoke hubs, competion spokes, and XR361 rims. I really thought hard about going carbon rims but they are $$$$!!! and the XR361's seem to be oddly light for alloy rims and are reasonably priced. In the end I couldn't justify to myself spending an extra few hundred dollars to save 30ish grams per wheel (comparing to chinese carbon). These are the second set of wheels I've built and from what I read there's no advantage either way mechanically speaking for j-bend vs. straight pulls so I went with the SP for coolness factor on this build. Gotta say I'll likely go j-bend for future builds if I have the choice for ease of building. The wheels are topped off with Conti Speedrides - I really like these tires.

For comfort I finished off with Ergon GS1 grips and a Fizik Arione CX saddle. Final weight as pictured is 9.1kg. I'm super happy with this build and (so far) don't have any plans to change anything. Im curious though what others think of the build decisions, or if they would have done anything differently.

Take care!
Ryan

Dragum

Very nice carbon hybrid! I preffer 38-28/11-42, but you know what doing. 9,1Kg is realy awsome, realy fast bike for citys.

badger1

Very nice, and smart, build.

headwind15

The frame looks small, you have a sickening amount of seat post sticking out of the frame, looks like you are close to six feet tall riding a 16 inch frame. Must be a 400 mm seat post.

epnnf

Who told you theres no diff between straight pull & J bend spokes? There are differences. (of course, I cant remember what they are Id have to look up @ The Bicycle Wheel by Brandt)

Ryan_M

I'd like to see what you've read and where as to there being any significant difference between the two. I read "Professional Guide to Wheel Building" by Roger Musson as well as tons and tons of googling, some have their preferences but it seems unanimous that the pros and cons of each are a trade off and pretty miniscule.

headwind15

The difference between straight pull and j bend spokes is significant because 90% or more spokes fail (break) under load, because of the stress from bending the spoke during the j bend spoke manufacturing process. Eliminate the bend and you have a spoke with a lot less chance of breaking.

epnnf

The Bicycle Wheel talks bout how radial spokes carry no torque. But of course they have to carry torque, after the hub rotates ahead of the rim. At this point the spokes are no longer truly radial. "...this motion increases spoke fatigie, and spoke rotation in the flange causes wear. As radial spokes wind up under torque, they become appreciably tighter causiing high rim stress and, in some instances, flange or rim failure. Looser spoking would reduce windup induced tension, but it would also reduce wheel strength. ... Even thought they transmit no torque, front wheels should not be spoked radially because high radial stress can cause fatigue failure of their flanges. . . . Radial spoking has no aerodynamic advantage over other patterns because near the rim, where the spokes produce the greatest drag, they occupy exactly the same positions, regardless of pattern."

Ryan_M

Ahh you're talking about radial lacing pattern, not straight pull spokes.

epnnf

Sorry, I thought radial & straight pull were the same thing.