My Sixth Motorcycle - 1975 Yamaha RD350B Reincarnated



It's finally done! I started it up in mid-February, 2004, and it was the first time it had run since sometime in 1985. It is basically a 1975 RD350B with a bunch of 1978 RD400E parts, and a bunch of aftermarket parts. My intent with all of the modifications was to improve the performance and reliability, and reduce the maintenance required, while still preserving the classic '70's look. You can be the judge of how successful I was.

The RD400 parts include the brakes, front forks, top triple clamp, front fender, grab bar, carburetors, wiring harness, instrument panel, tachometer, speedometer and handlebar switches. I had to modify the right handlebar switch so I could turn the lights off (helpful if you need to start it with a weak battery) as the 400E had the light switch fixed in the ON position to meet the US headlight regulation. The aftermarket parts include a Newtronic electronic ignition system, a Rick's rectifier/regulator, tapered roller bearings for the steering head, a Spec II needle bearing swing arm kit, K&N filter and Y boot from Pro-Flo, DG exhausts from Pro-Flo, Progressive Suspension fork springs, Koni shock absorbers, Bikemaster G.P. Touring handlebars, a Shindy front brake master cylinder and Russell stainless hydraulic lines front and rear. The original cable-operated clutch was a bear to operate so I converted it to hydraulic using a Shindy master cylinder, Russell hydraulic line and a slave cylinder from a Suzuki 1200 Bandit. The tires are Bridgestone BT45's. I had the seat recovered at Sargent Cycle Products and used some Ken Sean mirrors I got at Dennis Kirk. I replaced the original 25/35 Watt sealed beam headlight with a 55/60 Watt quartz halogen unit. Everything else is pretty much stock RD350. My friend Matt did a fine job repainting most of the parts. For the tank, side covers, headlight shell and headlight brackets, I decided to go with the metallic blue instead of the original Portuguese Orange to hopefully attract less "official" attention, but I doubt this will help due to the extreme noise from the DG pipes.

One of the more troublesome modifications was trying to use the RD400 wiring system. I originally decided to do this to take advantage of two features - the RD400 has self-canceling turn signals, and it has an electronic voltage regulator. Well, I discovered that the RD400 voltage regulator is incompatible with the RD350 alternator. I originally bought an Electrex rectifier/regulator to fix this, and ended up with the Rick's rectifier/regulator after the Electrex unit failed. Also, when I finally got the bike on the road I discovered that the self-canceling feature didn't work. I had to buy a new $80 control module to fix this. So I ended up having to spend over $200 to make the RD400 wiring system work, but I do how have an up-to-date voltage regulator, and self-canceling turn signals, so I guess I can't complain too much.

If you'd like more details on some of the modifications, check out my RD350B Modifications Page or click on one of the links below:

1. Electronic Ignition        2. Rectifier/Regulator        3. Air Filter Kit        4. Exhausts        5. Forks

6. Fork Springs        7. Shocks        8. Front Brake Master Cylinder        9. Hydraulic Clutch Conversion

10. Mirrors        11. Seat        12. Headlight        13. Tires        14. Rear Disc Brake        15. Intake Crossover

16. Battery        17. Rearsets        18. Swingarm Needle Bearing Kit        19. Steering Bearing Kit

20. Carbs & Jetting        21. Toolkit        22. Handlebars        23. Horn        24. Fuel Tank Crossover

25. Ignition Coils        26. Wheels

Here is a photo of me with a couple of other Yamaha 2-strokers that was taken in September, 2005 at a classic motorcycle poker run in Thurmont, MD:

In case you couldn't figure it out, that's me on the left. The other guys were regulars on the USA2strokers forum, which is how I met them.

More Photos:

Useful Files:

        RD350B Parts Book PDF                              RD350B Service Data

        RD250B/350B Wiring Diagram                     RD250B/350B Connection Diagram

        RD250/350 & 250A/350A Wiring Diagram    DS7/R5C Wiring Diagram

        DS7/R5C Wire/Cable Routing Diagram          RD250/350 Wire/Cable Routing Diagram

        RD350/A/B Wiring Diagram PDF                  R5/RD250/350 Charging System Manual

        RD400C-E Wire/Cable Routing Diagram        RD400F Wire/Cable Routing Diagram

        RD400C-E Wiring Diagram PDF                    RD400 Turn Signal Self Canceller Info

        RD400 Charging System Manual                   RD350B Owners Manual (2.5MB)

Technical Service Bulletins:

        Air Filter Info                                            Autolube Pump Adjustment

        Autolube Pump Info                                  Autolube Pump Service

        Battery Band Info                                      Carb, Air Filter Changes

        Carb Modification                                      Carb Setting Changes

        Clutch Slipping                                         Crank Specs

        Headlight Damper/Collar Info                     Key Info

        Oil Nozzle Sealing                                     Plug Fouling Info

        Plug Fouling Checklist                               Plug Fouling/Performance

        Plug Fouling/Troubleshooting                    Primary Drive Seal

        Seat Cover Info                                        Service Data

        Speedo/Tachometer Info                           Transmission Circlip Info

        Transmission Correction

Useful Links and Parts Sources:

        Bike Bandit - Great source for OEM parts. They have online parts diagrams for Yamaha bikes and indicate which parts have been discontinued. Their prices are generally lower than my local Yamaha dealer.

        Bolt Depot.com - Good source for nuts and bolts, especially stainless steel.

        Cyclepages.com - Good source for aftermarket parts and accessories. Their customer service is not great, but I've always gotten what I've ordered. Update: They seem to have gone out of business, so I have removed the link.

        Dennis Kirk - Good source for aftermarket parts and accessories. Great customer service and quick shipping.

        Flanders Company - Source for vintage parts and accessories. I haven't used them but have heard good things.

        Friendly Yamaha - Great source for OEM and aftermarket parts. Great customer service and quick shipping.

        HVC Cycle - Great source for vintage RD parts. Great customer service and quick shipping.

        Parts N More - Great source for vintage RD parts. Low prices and quick shipping, considering they are in Canada.

        PowerSportsPro - Good source for OEM and aftermarket parts. Shipping can sometimes be slow.

        Reproduction Decals - Source for vintage motorcycle decals. I recently bought a set of RD350B sidecover decals from them. They are not exactly the same as the OEM decals, but are of good quality and are close enough for me.

        Sargent Cycle - Great source for seat modifications and recovering.

        Sirius Consolidated - Great source for vintage carb kits. Great customer service and quick shipping.

        Speed & Sport - Great source for New Old Stock Yamaha parts. Great customer service and quick shipping.

        Yamaha USA Parts Diagrams - Great source for parts diagrams for all Yamaha bikes back to the mid '60's. They have also included technical service bulletins and service data for most of the older models.


This page was last updated on December 30, 2013

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