Yamaha XS400 Technical References

Updated 02/10/2015

Listed below are quick-reference links to threads in the forum on specific XS400 technical topics. Not all of the links below are to completed articles, but all contain at least some useful information on the topic. The list is a work in progress so if you can't find what you are looking for, try the Forum Search feature or browsing the main forum by Tags. If you're knowledgeable on a specific topic that is not well represented below, consider starting your own XS400 technical thread in the forum and it will most likely be included in the list below. A big thank you to everyone who has contributed so far!

* Newly Added

Engine and Transmission

How To: split your engine crankcase
How to check the oil level in your XS400 *



Carburetors, Fuel, Intake, and Air Filters

XS400 2 into 1 carburetor
Mikuni BS34 air intake jets/passages
Carb Adjustment
Jetting Guide
Jetting tip


MAC 2 into 1 Exhaust Install


XS400 wiring diagrams
How To: rewire an XS400 *
Charging system upgrade - Permanent magnet alternator *




Removing fork caps
Lowering forks

Wheels and Drive



How To: XS400 twin disc conversion (dual disc brakes)


Making cables

Maintenance and General Troubleshooting

XS400 Manuals


History of the Yamaha XS400
Polishing made easy


How To: make a bottle style manometer *


How To: Make your own Knee Dent Tank

Identifying your XS650, VIN Numbers


Yamaha XS400 Technical Article Suggestions

Listed below are some XS400 technical topics that would make great technical articles. Some of these topics are briefly covered by threads in the list above. The threads could use improvement or a new comprehensive article could be created on the topic. Consider helping the XS400 community by creating a How-To or technical article on any of the topics below.

  • Fitting a hardtail
  • Caliper service/rebuild
  • Dismantling rear shocks
  • Steering head taper bearing swap
  • Swingarm bronze bushes swap
  • 2-1 Carb manifold
  • Shortening cables
  • Wheel bearing replacement
  • Carb cleaning and rebuild
  • Engine rebuild
  • Timing
  • Cleaning a rusting tank
  • Torque specs and torque patterns
  • How to remove the starter

General Motorcycle Technical References from XS650.com

* Newly Added