Builder comment : Grand Bois, Mr. Ikuo Tsuchiya

Frame design concept While maintaining the necessary and sufficient frame strength and pursuing weight reduction by providing the necessary and sufficient functions as a touring bicycle. Also did not reduce the weight by easy drilling, but made efforts for lightweight processing that combines beauty.
Parts selection
While securing the gear ratio required for touring with the rear 10 speed and pursuing the limit of weight reduction by not only selecting the lightest parts but also modifying it in the workshop.
Completed bikeBased on the front single, we pursued weight reduction and individualization by brushing up the bicycle that participated in the 2017 France tournament.
Points for
Based on RINKO, which is necessary as a Randonneur, we have developed an ER system that allows you to easily attach and detach the front and rear mudguard run around in the same shape as a general road bike.
Reconsiderations Due to insufficient testing and examination of the lighting system, the attachment band of the dynamo for the tail light of the mudguard stay was damaged in the downhill section of the gravel. It is necessary to reexamine the mounting method in the future.
Which team are
interested in?

Rider Comment : Mr. Takeshi Maeno

Impressions of the
climbing section
The pace of the lead group after the start was too fast, so I slowed down before it became painful and continued to climb to Kasa Pass at my own pace. I joined SILK team on the way and eventually went along the way to the goal. I think the existence of each other was a good stimulus for the climbing sections of Kasa Pass and Shibu Pass. Both the Kasa Pass and the Shibu Pass in the liaison section, which competed for climbing, are high-altitude passes, so I thought it was essential to have equipment that could respond to changes in the weather.
Impressions of the
Gravel Downhill
On the descent of the Yuzawa forest road, there were many scenes where the grain of gravel was large up to the middle point, Enma Bridge, and I wanted thicker tires. Since the road surface became tight after Enma Bridge, we were able to descend at high speed by taking advantage of the performance of the ultra-lightweight and supple 650 x 38B tires. The tires used are slick, but the flexible caging catches the road surface even in the corners of the pavement and grips it, so you can enjoy cornering with confidence unless it is floating sand or deep gravel. The course was a forest road that made me want to slow down a little and take pictures of the beautiful scenery that sometimes appears if I run on a normal touring.
What do you like?Very light for a Randonneur with 650x38B tires, mudguards, front carrier, hub dynamo and leather saddle. Of course, lightness is not everything, but it is easier to handle while riding, and above all, you can carry a wheel bag with less burden when traveling. Generally speaking, a Randonneur has a dull image, but I think that it became an example of a bicycle that you can enjoy various road surfaces lightly if you decide the purpose and manufacture it.
Points to improve Aiming for lightness, I chose the lightest model on the market for the front hub dynamo, but I felt that the front wheels were twisted due to the narrow flange width. I thought it would be even lighter if I replaced it with a model with a wider flange because it could be increased by several tens of grams. Also, since this bicycle is a model for running JBT, some parts are for so-called decisive battles. If you use it regularly, you should replace the sprocket with one that emphasizes durability. Still lightweight enough.

 Participating bicycle details page. (Link to Grand Bois blog page)

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