Honda CB900F BolDor Restomod
In our desire to simplify things, we like to put names to everything in order to avoid long explanations trying to define what we are showing. Thus, the number of styles in the motorcycle building world increases day by day. From Custom we go to Cafe Racer, Scrambler, Street Track, Japanese Custom, Bosozoku, Street Fighter, etc. Restomod is being more and more popular these days, combining the idea of restoring and modernizing or modifying. Amazing Restomods can be seen over Japanese cars like 1970s Mazda coupes - RX-7. RX-3 - and Toyota Celica as well as obviously American muscle cars and SUVs from both countries, Sport Cars from Germany and UK an many more. The main characteristic on a Restomod is keeping the essence of the original model, modern parts are added. From here, the sky is the limit - or what is the same, the budget. Inverted forks, oversized radiators, latest generation carburettors such as Lectron, swingarms and suspensions from modern motorcycles... everything you can imagine and afford but keeping the essence of the original motorcycle - in this case.
This is the idea behind this CB900F BolDor. Keep the beautiful line that Honda managed to define in this model and its twins CB750F, CB1000F and CB1100F in the 80's, improving some of its aspects within a moderate budget.
The donor bike was in fact a non stock model but already incorporating some we can call improvements compared to the stock motorcycle. The French builder Martin sold a limited series of these motorcycles and other Japanese brands with some improvements on his own. Nothing specially fancy compared with the huge custom parts catalogs current manufacturers have. The most obvious are the gold Kawasaki-made alloy wheels that stand out compared to the double-petal ones of the stock model.
The inspiration for this project came from Japan, where many clubs and individuals make restomod an art. Just try to wander around Instagram a bit to see the motorcycles that those masters are able to buiuld, investing a lot of time and money. Without those budget resources, we decided to invest our efforts in the rear end - very weak in its origin - the braking and the final look of the bike. In the picures we liked of Japanese restomod motorcycles, the rear end looks higher and snubbed, giving the motorcycle a more aggressive appearance without falling into the Street Fighter. Another thing we didn't like is the upright riding position given by the stock clip-ons. Lower handlebars close to the fuel tank were a "mandatory" option on our bike. Finally we decided to improve the engine cooling by adding a bigger and modern oil cooler which also improved the front end look of the bike compared to the tiny and almost invisible stock oil cooler. Donor bike also had aftermarket turn indicators "modern" and smaller, but we believed that the original ones enhanced the retro look and matched perfectly with the ribbed taillight and the very classic original headlight too.
Rear swingarm comes from a Yamaha XJR1300 due to its size and fitting. In Japan, the most sought-after swingarm is that of the Suzuki Katana, but that motorcycle is already very difficult to find in its country of origin, let alone in Europe, where very few units arrived. Obviously we could try any type of swingarm even a monoshock absorber, but remember we had a tight budget and the Yamaha option was optimal in terms of cost and set up. With the swingarm, we also purchased the double-piston rear brake caliper and the 4-piston front ones from the same XJR in order to provide the bike better braking performance. Front master cylinder pump is a very effective Nissin radial which offers great performance and feeling for those calipers.
Since the Yamaha swingarm is noticeably wider than the original at the rear of it, we had to manufacture a a new adapter for the rear rotor. Also, the swingarm is longer than the original which forced to replace the chain with a longer one. New front and rear tires were included in the budget, the latter 160 wide and with a lower profile than the original, which improves both the grip and traction of the motorcycle and its general aesthetics. In the aesthetic section, we eliminated the end of the rear fender to leave that area clean and accentuate that snub line we talked about before. Rear shock absorbers are usually updated with modern ones, such as the well-known Ohlins. The tight budget and the good condition of the originals led us to keep them. The fact that the Yamaha swingarm mounts are a little further forward than the stock one accentuates the initially sought after rear lift. However, as the new swingarm widens at the rear, some steel extensions had to be manufactured for them in the frame.
Front end and again due to the tight budget, we were not allowed to update the original fork, for another ideally inverted. This change involves not only changing the forks but also the triple clamps and with them also the front wheel. To keep the original Martin rims and stick to the budget, we opted to upgrade only the brake calipers to modern Yamaha 4-piston calipers that, together with the Nissin radial pump, make a perfect combo. Front braking has improved significantly with this change.
As a final detail, the front fender was changed for a brushed steel one, very close to the tire.
Finally, the seat that the donor bike had had already been modified in a way that reminded a Cafe Racer end. To recover the original appearance in a Restomod, the foam was reshaped and upholstered again to match the original found in the bike. For the exhaust line we chose a 4in1 painted in anti-heat black and finished with a minimalist muffler offering a very sporty sound without being an open exhaust.
A restomod with a tight budget that allows you to invest in more transformations in the future without having to take steps back and that keeps the original silhouette of the bike with a very modern touch in our opinion.
CONTACT with us
If you liked any of our projects and you wonder how much it may cost or you are interested in some of our ideas for your motorcycle, do not hesitate to let us know.