The CB400 Rectifier/Regulator Question

compiled & edited by Kristian #562
Please read the Disclaimer before attempting any work in this FAQ. 

Following Chris Ratay’s comment on the Honda CB400 Regulator in a 2002 Sprockets and HsN’s comment on the capacity I did a little follow-up:

Q. Is Chris’s Comment Valid?

Why? Well, the wiring, VR size etc may all look OK from the outside, inside the VR may not be up to the 280W output of the F650 alternator.

Erin & Chris Ratay's Original Comment

"FYI: We confirmed we can use a regulator from a Honda CB400 -- it is exactly the same shape, with mounting holes in exactly the same places, and 6 wires.  Price for BMW part here is probably around $125, the Honda part is US$55.  The only diff is the color of wiring - 4 wires are the same: 3 yellow, 1 red-white; for use on BMW, need to swap positions of the brown (earth) and green wires - Honda uses green for earth."

As far as I am aware Chris & Erin did not actually USE the CB400 regulator, it just looks very similar.

Electrex USA shows the RR71 with a G7 Stator (F650 1997-2001 G7 $151.00 RR71 $134.00.)

Table 3 below also shows the 3 Hondas that are on Electrex site with a G7 Stator.

These are the: VT500C Shadow ('83-86), VT500 FT Ascot('83-84) and VLX600/VT600 Shadow ('88-2001), along with some other bikes, but the RR's are different, unfortunately (RR65, RR25, RR25*). This is also clear on Table 3.

This site has the Wiring of the CB400 Reg.

• http://www.twizzlecustoms.com/mailorder/hi-level/ign.htm
• CB400(4)        
• CB250/400N

This site has General info on CB400 incl. Alt/Reg Problems

• http://www.umgweb.com/member1/hcb40501.htm

This site gives a CB400 Regulator Model Number 715536

• http://www.gear4bikes.com/acatalog/Honda_Regulator_Rectifiers.html

Inputting the number 715536 at this site, this regulator is also on these bikes:

• http://www.daves-spares.co.uk/RegRec.htm

All Honda – Table 1

Searching on 715536 in General throws up this with another list of Regulators tying in with Electrexusa’s naming system, but has no RR71, which is what Electrex say is for the F650.

• http://www.bbbikeshop.co.uk/acatalog/Browse___Best___Buy_Honda_Reg_Rec_s_147.html
• http://www.electrexusa.com/electrex_regulators_BMW03.html  RR71 $134.00!

Interestingly the Search also turned up this site which gives another number 615-218* but says “SMALL MODIFICATION NEEDED”. Perhaps the RR71 has that small modification from the RR18 (Was it RR18?)

• http://www.sudco.com/electrex_bmw.html

Looking at this page for Hondas on the SAME site

• http://www.sudco.com/electrex_honda.html the 615-218 fits a plethora of Bikes, similar to the above list.

All Honda Table 2

• No other Bikes from the list of bikes below, apart from the HONDA, has the same Regulator as the BMW.
• BMW, Cagiva, Ducati, Honda, KTM, Kawasaki, Norton, Laverda, Muz, Suzuki, Triumph, Yamaha
• Interestingly, the CB500 also has “SMALL MODIFICATION NEEDED”

 Repeating the same exercise for the Generator (Stator) yields these results:

• BMW 650 has a 615-007

Various  - Table 3

From Both Tables 2 & 3 it would seem that there is no Single Bike with the same RR and Stator.

This is the location of the Wiring Diagram for the CB Series Bikes between 350-550cc:
 

• http://smokeriders.com/Technical/wiring_diagrams/Honda/CB_CL/CB350F_CB400.jpg
• http://smokeriders.com/Technical/wiring_diagrams/Honda/CB_CL/CB500.jpg
• http://smokeriders.com/Technical/wiring_diagrams/Honda/CB_CL/CB550.jpg
• 

So to answer HsN’s question, all we have to do is find the biggest charging system of one of those bikes in Table 1 or 2 and if it is greater than the Classic, it’s a goer. (i.e. it'll work)

I did TRY a few searches on CB400 Alternator, but so far have only found out this one:

• The CX500 80´ has power of alternator 170W according the manual. (This is less than the Classic’s 280W).
• Is it worth asking the Board to get out their Clymer's/Hanes for the Bikes in Tables 1 & 2?
• Haakon #626 Came up with this Table: It shows the 1982-83 CB400 Alternator to only put out 150 watts, clearly too low for the Funduro (Classic 280 W).

Alternative VR Sources:

Moving on then I found that funnily enough these guys in Greece actually make a Regulator for the F650, for 80 Euros.

• http://www.sxelectronics.gr/sx25e.htm

SXelectronics use the same regulator on the:

• Suzuki BANDIT 250/400 SX7 80 and the
• Suzuki LS 650 SAVAGE SX7 80

Don't forget Electrexusa have one that works:

• Electrex USA uses the RR71

However none of the Hondas, including the CB400 Four, use the SZ7 Model, so you have to ask if that CB400 really is one you can use?

Misc. VR sites:

• http://www.tympanium.com/app.html
• http://my.execpc.com/~milwcycl/ele1.htm
• http://www.newtronic.co.uk/pages/electronic_ignition.html
• http://www.honda4fun.com/modelli/cb400.html

Conclusion:

We do NOT think the CB400 VR will work, but the research brought about other Alternatives and MAYBE another Jap Bike with a VR that does work. We have yet to find it.

Cheers,

k