The Charging Mod Illustrated

[Crass]

Having just done the charging mod described in the archive here https://oldskoolsuzuki.info/archives/tag/charging-system  I thought it might be helpful to others if I described how I did it with a few pictures.  I know some people find electrics daunting and a picture can be worth a thousand words.  First of all, however, just to make clear that all credit for the mod goes to jonny1bump who posted it all up in the first place, all I'm doing is showing how I carried out his work on my bike.

So first of all you need to find the connector block under the rider seat shown here arrowed in green -

This has one red and one orange wire into it out of the loom and two reddish cloth covered wires out of it to the alternator.  You need to cut the orange wire on the right - give yourself at least about an inch and a half of wire still coming out of the connector block, so you'll need to open up the loom a bit.  DO NOT CUT THE RED WIRE, leave it alone.

Now you need to splice in two new lengths of wire onto the cut ends.  I used orange 3mm 30A rated thin wall insulation, as the closest match to the original.  You don't want to be using thinner wire than the original - thinner wire = greater resistance = voltage drop and this is the problem you are trying to cure.  You can crimp the wire on, personally I prefer a soldered splice, then seal the splice with heatshrink insulation  On the other end you need to crimp on female spade connectors, which to match the terminals on your relay will most likely be 6.3mm.  Use double crimped ones which grip the bare wire and the insulation.  Again, as well as a crimp I like to put a bit of solder on my crimped end.  I also slipped insulators on the wire to cover the blades to make everything 100% weathertight.

Now you need to make up two more lengths of wire, same type as before but this time a black length and a red length.  On one end of the black wire you want a double-crimped 6.4mm round battery terminal, on the other end a 6.3mm female spade with insulator.  The red wire is slightly more involved as this mod bypasses the 30A circuit breaker in the original wiring, thus potentially leaving the positive feed to the trigger circuit unfused - but we're going to sort that.  You want a 30A rated waterproof inline mini blade type fuseholder, which looks like this -

The 30A rating is so that the integral wire tails it comes with will be the same rating and diameter as the rest of the wiring you are installing - again because you don't want to introduce thinner wire into the circuit.  But you want a 10A fuse in it, don't put a 30A in it, that's way too high for this circuit alone.  On one end of one of the wire tails fit a 6.3mm female spade with insulator.  Extend the other tail by splicing on extra red wire and sealing the joint with heatshrink insulation.  The female spade will attach to the relay and the end of the red wire will attach to the positive terminal of the battery, so measure things out and, before attaching a double-crimped 6.4mm round battery terminal, thread it through the terminal insulator on the battery cable, as this is easier than trying to fit it through with the terminal attached.  When you've done that attach the terminal.  The new terminals sit on top of the existing battery lead terminals.

The relay I fixed to the undertray next to the fusebox as you can see.  Drilled through the undertray and used a stainless nut and bolt to secure the relay bracket.  I also put a bit of foam between the bracket and the undertray to provide a bit of damping but this might be overkill, as the plastic undertray is flexible anyway.  I put another little bit of foam between the relay and the fusebox cover, so that is held firm and damped.

You can see in the photo below how I've routed the wires, so you can follow this and cut to the required length before starting.  I used the groove in the undertray as a duct for them to pass underneath the fusebox, which secures them neatly.  The inline fuseholder is positioned between the relay connection and before the red wiring passes underneath the fusebox, so it's in a logical position close to the fusebox.  The loom was resealed with self-amalgamating tape leaving the orange wires passing through.  The red and black wires are cable tied to the battery wires, then cable tied along their length to the loom or frame.  You don't want unsecured wires flapping about, they get fatigued over the years, work harden and then you get annoying internal cracks.  A tidy bike is a reliable bike .

So the wires go as follows - orange from the ignition switch side of the loom (i.e. from the right hand side as you're looking at the connector block in the first photo) goes to one of the coil terminals on the relay; black wire connects to battery negative and the other coil terminal on the relay; the other orange wire, from the alternator side of the loom (i.e. from the left hand side as you're looking at the connector block in the first photo) goes to one of the switch terminals on the relay; red wire connects to battery positive and the other switch terminal on the relay.

I think the pictures below should illustrate this all clearly.

Other ways of doing all this are available, this is just my take on the job.

Edited December 5, 2018 by Crass

[Swiss Toni]

Needs to be stickied, methinks!

[wsn03]

Brilliant, i can follow this (im electrically useless). Should be stickied, only found out about it by accident 

[wraith]

Good man 

[Dezza]

Interesting - would this mod reduce the likelihood that an older bike fitted with one of these new fangled lithium batteries becomes engulfed in a ball of flames?

[Crass]

On 11/8/2018 at 1:49 PM, wsn03 said:

Brilliant, i can follow this (im electrically useless). Should be stickied, only found out about it by accident 

If you ask one of those nice mod peeps they might do it.  Glad it helped you.

[wsn03]

Anyone know the names of the relevant mods?

[Captain Chaos]

stickied it for you all to enjoy on a daily basis

[wsn03]

Thanks Captain !!

[B12Mick]

The pictures really help to understand the mod - nice one 

[yyt]

Before I'll have my say, I would like to make sure this is what you made:

 

 

 

                                                                            * pic deleted because containing inaccurate info *

 

 

 

 

Edited November 18, 2018 by Captain Chaos

[jonny1bump]

I connected the wire that you have marked to B straight to battery so direct feed with true voltage to take out any wirring corrosion. You could do as you said or method I used with inline fuse if your worried about protecting the wire.

This wire is basically telling alternator to wake up and work and is comparing the two voltages so imperative the alternator receives true reading to prevent it ramping up the output voltage.

Edited November 18, 2018 by jonny1bump

[jonny1bump]

Found my original drawing from way back.

Edited November 15, 2018 by jonny1bump

[Askamaskinservice]

14 minutes ago, jonny1bump said:

Found my original drawing from way back.

Perfect an OLDSKOOL drawing.

[jonny1bump]

The days before cad or my version.

Cardboard aided design.

[Askamaskinservice]

BINKY style

[jonny1bump]

Totally.

[Crass]

On 11/15/2018 at 11:22 AM, yyt said:

Before I'll have my say, I would like to make sure this is what you made:

No, that's not my understanding of what I've made.  In particular the mention of low and high current circuits on your diagram.  The only circuit you are altering is the trigger circuit, you are not cutting into the feed from the alternator to charge the battery.  As jonny1bump says, B is wrong, you're just feeding full battery voltage TO THE TRIGGER CIRCUIT when the relay is energised.  No mention of inserting a fuse in this wire in the original writeup, so I didn't, but to be fair there should be one as you have bypassed the existing fusebox.  Plenty of wire and space to put in an inline fuse to be safe, though.  Trying to work out from the wiring diagram what the correct rating for this would be.  It's only trigger voltage so 10A?

Edited November 17, 2018 by Crass

[jonny1bump]

You can put your blue B wire straight to battery thats what i did. If you worried you can use inline fuse.

But what I mean about B wire is your blue wire to B in your diagram not the black wire. 

It's better to put that wire directly to battery, this wire feeds IG the trigger wire via the relay. The original untouched black line feeding battery is wire from alternator putting power into said battery. This wire can corrode and melt.

My diagram is the hand written one not the above picture which is misleading.

 Don't over think it all we doing is feeding the trigger wire directly from battery via a relay which is now been switched on from ignition wire.

The voltage drop on this wire is pretty horrific through ignition switch which will not affect relay operation but causes total chaos with alternator control circuit ramping up voltage as it thinks battery is low.

I remember riding to Italy from UK in one hit got there battery was totally gone and swollen was new. Was bump starting it then, with luggage not fun, at that moment was determined to sort this.

Mines not like that now as I decided to make my own loom from scratch with complete different type of fuse box so all my circuits run completely independent of each other. No voltage drop now and running a tiny lithium battery with high compression. Have to admit battery is old now and starting to take a bit of waking up like an old engine with old thick oil. Most odd to see. 

Edited November 18, 2018 by jonny1bump

[jonny1bump]

Just noticed on original article there is note not to use cheap relays that is good point whoever added this and deffinatly worth considering.

Edited November 17, 2018 by jonny1bump

[Crass]

Yeah, personally I think an inline fuse in the wire from the battery direct to the trigger is overkill.  The way I interpret the actual wiring diagram in the manual is that the trigger feed does NOT go through the fusebox, way I see it is it goes from battery positive through the 30A circuit breaker to the ignition switch.  This mod bypasses the breaker, which a lot of people remove from the bikes anyway.  So I guess if you really wanted to be belt and braces you could put a 30A inline fuse in the wire from battery positive to the trigger circuit connection to replace this that you've bypassed.  Only way it would ever come into play as I see it is if you got a massive short circuit somewhere in the trigger circuit.

Edited November 17, 2018 by Crass

[jonny1bump]

You know I completely forgot about the circuit breaker I binned that in 1993.

The trigger wire is direct from ignition but ignition is fused well upstream if I remember correctly. Perhaps it was only the breaker Will have check workshop manual and refresh memory as ive done it completely different with my own loom. Don't think you would need such big fuse on the actual trigger wire itself as it's turning alternator on and monitoring. Need to keep eye on the red charging wire they like to melt at connector joints.

Edited November 18, 2018 by jonny1bump

[jonny1bump]

Crass your right it's all fed from breaker including main charging wire, hence high rating. Perhaps then for those who removed breaker we advise breaker be replaced with 30 amp in line fuse.

Edited November 18, 2018 by jonny1bump

[Buzuki]

 Also want to experiment with Suzuki alternator connection on my oilcooled 750 project where by me alternator internaly will be slightly modified and conected  in more conventional way , one more warning red light(12V/3W) will be added on the front small control board , that modified internal connection need three new small diode (1N5408) to be instaled , in these configuration any standard solid state voltage regulator can be used not only original Suzuki ,

any suggestion ? 

[Crass]

8 hours ago, Buzuki said:

 Also want to experiment with Suzuki alternator connection on my oilcooled 750 project where by me alternator internaly will be slightly modified and conected  in more conventional way , one more warning red light(12V/3W) will be added on the front small control board , that modified internal connection need three new small diode (1N5408) to be instaled , in these configuration any standard solid state voltage regulator can be used not only original Suzuki ,

any suggestion ? 

Maybe start a new thread on this one as it could get messy all mixed in with discussion of the original mod and leave people trying to follow one or the other subject a bit confused when referring to it in future?