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Discussion Starter · #1 ·
What is the original part number of the ignition switch for said motorcycle and please recommend a suitable replacement. My Triumph Replacement Parts Catalogue doesn't show the ignition switch.
 

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Discussion Starter · #2 ·
I'm hearing from Classic British Spares that the part number is:

O.E.M Part number is 30552, 066395, 39565, 99-7055, 39784, 54531899

I think I need to do more research prior to posting. Thanks.
 

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Discussion Starter · #4 ·
The manual isn't clear on this but is there a threaded collar surrounding the ignition switch that secures it to the side panel? ...meaning that the collar must be first removed prior to removing the side panel itself.
 

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Hi,

original part number of the ignition switch
recommend a suitable replacement.
O.E.M Part number is 30552, 066395, 39565, 99-7055, 39784, 54531899
Several wrinkles to be aware of here:-

. The picture of the ignition switch on page 90 isn't correct - it's of the switch used '66-'71 and '73-'78.

. The 5-figure number shown on page 91 - "39565" - is a Lucas number and NLA. But the switch is exactly the same as the "39784" number in the string you got from CBS, these were fitted to the T160 and '79-on twins.

. Be aware that what CBS - and the vast majority of other dealers - sell is pattern Wassell, that - in a bare-faced abuse of the English language - Wassell are allowed to call "Genuine Lucas". :rofl There are also non-Wassell patterns.

. I don't know how good Wassell versions of this switch are but Wassell quality control is generally an oxymoron. As for other pattern versions, in 1982, I replaced one with an original Lucas on the T160 I bought second-hand (the T160 I bought brand-new still has its original switch). With great care, you can dismantle original Lucas switches by prising the brown 'circuit board' out of the metal case, cleaning the internals, filling the case with petroleum jelly and reassembling. :thumb

. Whether you fix the original or fit a new one, drill a small hole in the terminals end of the switch, at what'll be the lowest point when the switch is fitted - lets out any water that gets in, rather than it swilling around corroding the internals.

is there a threaded collar surrounding the ignition switch that secures it to the side panel?
#21 "Nut" in the parts book.

Consider replacing this nut with one as fitted to '79-on twins (part numbers in the books here), then you can fit the accompanying cover. :thumb

At the other end, the electric-start Norton Commando also used this switch, and Norton made a more-waterproof cover for the terminals end of the switch - Norton part number 06-5723.

Hth.

Regards,
 

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Discussion Starter · #6 · (Edited)
Well, this morning in testing the original ignition switch there's barely any continuity at four of the detents (even though it's supposed to be a 4-position switch). One of the detents I can't even feel although I lubed the key with lubriplate a several days ago. This was all tested against the new Lucas 4-position switch and the results are incomparable: the Lucas tests correctly, the way it should, in all four positions. The new switch shows 4 groups of terminals on the backside labeled 1 thru 4:

1 = hot lead from the battery (brown and blue wires)
2 = ignition (white wires)
3 = lights (brown and green wires)
4 = who knows and it seems unused afaik

Testing the new Lucas switch, here are the results

pos'n 1 no continuity between the hot lead and terminals 2 and 3. This is the "off" position (key at 1200 hrs)

pos'n 2 continuity between the hot lead and terminal 3, the lights (key turned to the left at 1100 hrs)

pos'n 3 continuity between the hot lead and terminal 2, the ignition (key turned to 1300 hrs)

pos'n 4 continuity between the hot lead and terminals 2 and 3, the ignition plus lights (key turned to 1400 hrs)


None of the above occurs with the original switch, and when the key is turned the needle on my Simpson 260 barely moves, indicating poor contact and continuity between the internals of the original switch.
 

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Hi,

4 = who knows and it seems unused
The same switch was/is fitted to T160's and '79-on twins; on these models, the Blue wire supplying the headlamp on/off switch is connected here rather than the headlamp on/off switch being supplied by a Brown/Green wire.

pos'n 4 continuity between the hot lead and terminals 2 and 3, the ignition plus lights (key turned to 1400 hrs)
And terminal 4. So, with the Blue wire connected to terminal 4, you'll also have "the ignition plus lights". :thumb

poor contact and continuity between the internals of the original switch.
Your mission - should you decide to accept it - is to get that switch working.

Take it apart carefully (inside (to catch small parts making a bid for freedom) a large (so you can get hands and tools inside), clear (so you can see what you're doing) plastic bag).

This post will self-destruct in five seconds ... :)

Hth.

Regards,
 
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