XS Front End Swap for CB350
Hey guys, thought I’d share some info on the front end swap I did over the winter on my ’72 CB350. I decided to go this route for a number of reasons, but it started out as just wanting to beef up my fork tube diameter from spaghetti noodle thin 33mm to a sturdy 35mm. In doing research I also found that road racers look for triple trees with four bolt pinch mounts on the bottom yoke as apposed to the CB’s two, giving more clamping surface area and a more secure attachment. This left me with a few options but I decided to try out a Yamaha XS front end because of the added benefit of aluminum shouldered rims and a simple dual disk conversion. Took a lot of time researching and sourcing parts but here’s the quick version:
The assembled front end consisting of XS650 trees, wheels, and forks. Brake calipers and dual lines are from a XS750 and the brake rotors are from a XS1100. I used a super helpful Yamaha Part Finder website to figure out which parts are interchangeable between the different years and models.
Tapered bearing kit for CB350 from All Balls Racing works perfect with the XS stem, no modifications needed. I also bought a bearing kit for a XS650 thinking I would need to combine pieces of both but since I didn’t need it if anyone is looking to upgrade their XS bearings I’ll part with them for cheap.
Lower bearing in place and new upper bearing race installed. The kit replaces both stock ball bearing races.
Brake master cylinder and stainless lines I picked up from MikesXS.com
All in all I’m happy to have a rock solid front end. Being such a light bike dual disks are probably overkill… but it looks bad-ass and I’ll be able to stop using one finger. Can’t wait to get it on the road and test it out. I’m doing a shit-ton of other modifications to pretty much every aspect of this bike so I’ll share them as they get completed if you guys like.
9 responses to “XS Front End Swap for CB350”
Published - Jul 19, 2018
Always wanted the hardtop…