rewire - what size/spec of wire

[Ewan 500 K1]

Hi Folks, just got my engine back togeather today and its now ready to go back in the fram so that I can start to do a full new wiring loom for the cafe racer. This will be my first attempt at doing a full rewires, anyone got any idea what size / spec of wires I should be using for the various circuits ?

[LesterPiglet]

Something a step up from the installed fuses. This will give you an idea.

http://www.vehicle-wiring-products.eu/VWP-onlinestore/cable/standardcable.php

[Bryanj]

If given a choice you need a lot of small strands rather than a few thick ones as this gives flexibility

[Lobo]

Further blurb / possible help here...

http://www.autoelectricsupplies.co.uk/product/66/category/11

[matthewmosse]

The standard wire or 'high preformance / thinwall' stuff will I think do most of the wiring - I followed the guidelines in vwp catalouge (see link in above post) I re wired my 550k3 using the 'high preformance/ thinwall' stuff, I think I'd give the standard stuff a go next time as it wasn't that nice to crimp onto and I think the stock honda looms are better, also the std jap connectors insulation is a better fit on the basic speck wire. The thinwall stuff might be worth using if trying to have a skinny loom for cosmtic reasons.

[Ewan 500 K1]

thanks for those hints and tips, this form is just invaluable for grtting pointed in the right direction. Spent all day looking at the wiring and working out what I need to get ... what a state the old loom was in. So what I found was :

Headlight and charging circuits: cable OD = 2.5mm, core wires OD = 1.5mm..... which means the cross sectional area is 1.8mm sqaure , ie near enough 2mm. The core was made of 50 single strands of between 0.1 & 0.2 mm diameter

All the other wiring: cable OD = 2.3mm, core wires OD = 1mm.. ...which means it has a cross sectional area of 0.8mm sqaure, ie near enough 1mm

So plan is to order dome standard PVC sheathed 2mm wire for charging and headlight circuit and 1mm wire for the rest

[Lobo]

Blimey Ewan.... been doing your homework!  From this point on I suspect you've just installed yourself as resident guru on motorcycle wiring!
Good luck with the loom, be sure to treat yourself to quality bullets / crimping tool (ie not the cheapo stuff from Halfords etc)
Lobo

[Ewan 500 K1]

Blimey Ewan.... been doing your homework!  From this point on I suspect you've just installed yourself as resident guru on motorcycle wiring!
Good luck with the loom, be sure to treat yourself to quality bullets / crimping tool (ie not the cheapo stuff from Halfords etc)
Lobo

.. another excuse for a day in the shed ignoring all other responsibilities. Got a load of bullets a while ago but they dont seem to be ideal as the existing male bullets on various components dont sit in the female sides of the new ones all that snuggly.

[matthewmosse]

I often find the male bullets on old components appear a bit loose on new female fittings, I just give the offending female fitting a gentle squeeze with some pliers which proves to do the job. I use vwp sourced jap bullet connectors with seperate insulation btw. I prefer to solder the connections once made as I have a cheaper type crimping tool - my autosparks loom made with lucas bullet connectors - properly crimped with the bees knees tool costing £80 for the tool still has lost a number of connectors over the years but my slodered connectors have lasted better.

[mickwinf]

Hondas of this age used a slightly smaller bullet than other jap bikes so don't fit very well. Most new ones are the bigger size so I replace both male and female together.

[Ewan 500 K1]

Hondas of this age used a slightly smaller bullet than other jap bikes so don't fit very well. Most new ones are the bigger size so I replace both male and female together.

looks ,like I'll need to go with that then Mick, cheers. Least I'll get a handle on crimping by the end of it all

[Lobo]

Dunno how spec you want to be; but (eg) my '72 K2 & '77 400F both use 3.5mm bullet connectors. These are bloody hard to get, I've only ever managed to source them from the 'states.  eg

http://www.ebay.com/itm/5-Male-Bullet-Barrel-Terminal-3-5mm-20-18AWG-Insulated-MB352018IN-/250988766833?pt=Car_Audio_Video&vxp=mtr&hash=item3a7018a671

Plenty of (UK) places stock the 3.9 or even 4mm bullets, and as you might guess..they don't mate too well with your elderly jap loom. Mick's suggestion spot on if not needing OEM.

Gotta say, I bit the bullet (ha!) and spent £30 on 'the business' crimping ratchet tool - worth every penny & a sheer joy to use: such a buzz to get beautifull crimped OEM type connections, versus (my soldering) which often melts the cables & ends up looking very DIY. (One problem of soldering is it tends to harden the wire, making it more susceptible to failing from vibration. Furthermore, any overheats (poor connections) can melt the solder & cause the connection to fail - tho' unlikely I guess in our 'bikes)

If you want to 'see' said crimping tool its in my previous posting's wire catalogue link, in the tooling section, or here ...

http://www.autoelectricsupplies.co.uk/product/746/category/87

Enjoy!
Cheers, Lobo

[Ewan 500 K1]

Dunno how spec you want to be; but (eg) my '72 K2 & '77 400F both use 3.5mm bullet connectors. These are bloody hard to get, I've only ever managed to source them from the 'states.  eg

http://www.ebay.com/itm/5-Male-Bullet-Barrel-Terminal-3-5mm-20-18AWG-Insulated-MB352018IN-/250988766833?pt=Car_Audio_Video&vxp=mtr&hash=item3a7018a671

Plenty of (UK) places stock the 3.9 or even 4mm bullets, and as you might guess..they don't mate too well with your elderly jap loom. Mick's suggestion spot on if not needing OEM.

Gotta say, I bit the bullet (ha!) and spent £30 on 'the business' crimping ratchet tool - worth every penny & a sheer joy to use: such a buzz to get beautifull crimped OEM type connections, versus (my soldering) which often melts the cables & ends up looking very DIY. (One problem of soldering is it tends to harden the wire, making it more susceptible to failing from vibration. Furthermore, any overheats (poor connections) can melt the solder & cause the connection to fail - tho' unlikely I guess in our 'bikes)

If you want to 'see' said crimping tool its in my previous posting's wire catalogue link, in the tooling section, or here ...

http://www.autoelectricsupplies.co.uk/product/746/category/87

Enjoy!
Cheers, Lobo

Hey Lobo, being a cheapskate I went for the £9 crimper from VWP , seems to do the job oki doki. Looks like I'm heading for replacing everything with 3.9mm bullets , not arse aboout OEM really ... half the loom looks as if its off a 550 anyway it's got a wee diode in the nutral switch circuit (see diagram). The wore from the diode terminates in the headlight shell.. damned if I know wht it joined onto. ( i I labe all the wire end when I took it to bits, well err no actshully . The bike also has a 550 front end .. bit of a mongrel really.

  Anyone know who sells the best quality 3.9mm bullets .. ?

[ka-ja]

Hi,
     If its anything like the 400/4 , one of the wires goes to the clutch lever switch, the circuit makes sure you cannot start the motor in gear without pulling in the clutch-----Ken

[Ewan 500 K1]

Hi,
     If its anything like the 400/4 , one of the wires goes to the clutch lever switch, the circuit makes sure you cannot start the motor in gear without pulling in the clutch-----Ken

ha, that could be it .... reduntant wire from 550/4 loom as the 500 doesnt care whether the clutch is in or out ... as far as I remember !  In fact that must be it Ken.. looking at the 550 circuit diagram in the clymer manual ... the wire for the clutch switch is green and red like the one that comes from the diode to the headlamp shell in my handrawn diagram ... funny thing is the circuit diagram doesnt show a diode. Picture of the diode attached.