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I am helping a friend wire his '75 T160 project and I am trying to establish at which earthing point the starter +ve earth cable from the battery terminates and how long the cable is if possible. Also is it fixed to the main downtube (oil tube) to anchor the cable. If anyone has any photos of the way the harness is run and attached I would be most grateful as the bike did not have any wiring attached as a guide.
Many thanks,
Mike

The +ve starter cable attached to an extended inlet head/rocker cover bolt on early T160s.

http://www.classicbike.biz/Triumph/Parts/Trident/1975T160PartsManual.pdf
pdf p.20 Item 48 (21-2341)


According to the T160 manual, under the nut of the top right-hand engine plate bolt and where I have it on my T160 (although Stuart is likely to say it goes on the left-hand side).

http://www.classicbike.biz/Triumph/Repair/Trident/1975Triumph-T160.pdf
Section B1, pdf p.39 & 40.







The standard T160 isn't OIF so doesn't have an "oil tube". Securing the cable in the "lower" (engine plate) position on either side is probably unnecessary, just apply common sense.

Thanks LAB for the excellent information which was much appreciated and sorry about the oif info, I was getting confused with another project. I didn't think it went to the head/rocker box area as it must get pretty hot there and would over time affect the insulation.

Very interesting question.
On a T160 I recently rewired the old battery cables were corroded and the insulation brittle and cracked in places.
So I decided to replace with new ones.
A friend of mine in California recommended a set from www.motoelectric.com --they do battery cables mainly for Hinckley Triumphs but do offer a set for the T160.
So I bought a set and found that the positive cable (from battery positive to earth--sorry Stuart!) was too short.
It was 12" compared with 19" of the original.
The original was bolted to the top right hand bolt of the primary chaincase and the new 12" cable was too short to reach there.
So I looked at a couple of other T160s that I have which are readily accessible and found that on those the earth cable was bolted to the top bolt of the drive side engine mounting plate to frame (at the back) --sorry Les!. The 12" cable was OK for this run.
Now the old 19" cable looked very original to me so I guess either it had been replaced (wrongly) many years ago or the state of the build shop in 1975 was such that more than one location for the earthing point was used.
HTH.

No need for an apology. I was merely quoting what it states in the 'factory' manual (which, as we know, was only published some years later) although modern equivalent batteries can be taller than the original with the terminals reversed which can alter the length of cable required but then I make up my own starter cables the length I want.

(That motoelectric.com domain appears to be for sale as I keep getting directed to ad. pages)

Also, it seems there had been problems with the original LH rocker box 'earth' mounting position and extended bolt.

Hi Mike,


Ime of original T160's, they had the thick +ve earth cable attached in at least three different places, afaict roughly corresponding to whether a given bike's 'early', 'middle' or 'late'.

Les is correct about 'early' and 'middle' (bearing in mind the workshop manual wasn't compiled 'til the early 1980's is probably why John (Nelson) put that location in). To cheer Les up, on 'late' T160's, it could be fastened to either of the top nuts on the left-hand (drive-side) engine plate; this actually makes the most sense and the shortest route, as the +ve battery terminal is under the side cover at the front.

However, where exactly you attach the +ve cable is gloriously irrelevant ... the starter earths through its mounting on the engine ...

As you're rewiring the bike, few other ime:-

. The aforementioned standard position of the battery terminals - at the front of the battery, just behind the coils - makes it more difficult to fit the sidepanel. Much easier to work with the battery terminals towards the rear of the carrier (but still keep +ve under the sidepanel and -ve on the oil tank side) or use a Motobatt with four terminals and use the rear ones.

. Beware sizing new cables based on the old ones. Original ones were 37 strands of one of two sizes; either is very inflexible compared to modern cable, the smaller size is too small for Amps sometimes drawn by the standard starter. I use http://www.vehicle-wiring-products.eu/product.php/1030/battery-starter-cable, selecting "196/0.40 25mm sq. 9.8mm O/D, 170 Amps" in the dropdown under "Size:".

. I use these terminals, "6mm hole" at the battery, solenoid and starter, "8mm hole" or "10mm hole" depending whether you're attaching to 3/8" or 5/16" o.d. engine plate bolt; depending on the starter, one of the terminals might need opening out to 7 mm.

. If required, VWP will make battery-to-solenoid, solenoid-to-starter and engine/frame-to-battery cables to order.

. Standard harness has one or two thin Red wires attached to a ring terminal for battery +ve. If you and your friend haven't seen the relevant NVT Service Bulletin, either tape the terminal and wire/s clear of the battery terminal or only attach one wire with a 'main-size' (35A tubular, 15A blade) fuse in it. Another Red wires terminal is attached to one of the head bolts/studs through a rocker-box and, if the thick cable becomes loose or disconnected, using the starter will complete the circuit through the Red wires between head and battery +ve connections ... or at least will attempt to complete ...

. If your friend hasn't done it already, take the starter apart and give it a basic service - wipe off grease and carbon, small amount of new grease on the actual bearings, check brushes, etc.

. If your friend's bike still has the steel sidepanel and timing-side coil cover (attached to the front edge of the oil tank), he knows the only replacements come from T160's being broken, and simply various upper and lower limbs in exchange won't be enough? Because one coil cover fell off and got run over on the A30 near Heathrow years ago (oil tank screw threads stripped by over-enthusiastic dpo ), I've long used L.P. Williams Legend grp oil tank covers. However, I'm contemplating using LPW grp sidepanels too. Btw, the standard T160 sidepanel securing screw does work, as long as the sidepanel thread isn't worn/stripped and the correct part-numbered squashy grommet is in the frame hole.


This suggests your friend has bought an off-the-shelf harness already? If so, pity; lack of a decent one in 1982 persuaded me to do my first rewire and I've yet to see anything that's changed my mind.

Nevertheless, ime best routing for an original harness was along the left-hand (drive) side of the main frame top tube, around the left-hand side of the steering head and in through the headlamp's central hole; the wires to the console between speedo. 'n' tacho. branched off between frame and headlamp. My first T160 came with the harness routed on the right-hand (timing) side and the White/Yellow wire between kill switch and coils (later Rita e.i.) failed in less than two years where the harness flexed around the steering head. Otoh, my second T160 came to me at five years old with the harness routed as I've advised and White/Yellow wire still intact.

Hth.

Regards,

You are right, Les, the motoelectric site looks as if it is dead.
I bought the cable set for the T160 from them in June of this year.
They have obviously gone down since then.
Apologies if I misled anyone.

Sounds as if the battery positive would be best connected directly to the engine as this is where the starter motor "earths".
This was presumably the reasoning behind my "original" cable being bolted to the top right primary chaincase bolt.
Not too happy about earthing via the frame---shades of no red wire to the rear light---so maybe I should put another link in from the top engine mounting plate bolt to the chaincase.
Certainly wouldn't hurt and maybe it would be an improvement---two possible paths to earth (sorry, Stuart--to the battery positive terminal!).

Hi Richard,


If it's "bolted to the top right primary chaincase bolt", it's bolted to the engine (just under the sidepanel and battery carrier)? Fwiw, that's where it's been attached on both my T160's for over thirty years, and both Lucas starters function perfectly. :bigt

Hth.

Regards,

Stuart, in another conversation I think you mentioned using flag terminals on the big starter cables. Am I correct?

Hi Steven,


Originals had some flag terminals (not all of them). I have new cables made by VWP and they don't offer flag terminals when making cables.

Hth.

Regards,