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' 70 brake switch wire secured to chainguard ? #528715
02/17/14 11:58 am
02/17/14 11:58 am
Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
KC in S.B. Offline OP

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KC in S.B.  Offline OP

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Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
Powered up the system on the rewired '70 TR6C yesterday, and aside from a spark notch on the rear fender from a hot battery wire... crazy... no SMOKE! So far, I think I have a good layout and stuff will work. A few details need to be worked out though:
How are the wires back to the chain guard brake light switch secured to the Guard? It seems like running them down the frame tube, and just having them attached to the switch is not enough support for very long with the swing arm moving up and down constantly. Is there some OEM way to clamp them on the guard?
Also, I have a simple Radio shack toggle switch to power the headlight circuit at the moment. The OEM switch would be the Black flip lever I think, right? It seems like that is over kill in that small headlight shell, but I guess that would be correct on a TR6C?
What fuse rating do you fellows recommend? The temporary 25A did blow when I was arc welding the rear fender.... wink , but I expect most actual issues would be less intense. My smallest wires are 16 gage. And if I remember correctly, you are protecting the wires by blowing before they melt. You would have to calculate the draw through the devices for each wire used, and pick a fuse to protect the weakest link..... shocked. That's WAY too much trouble, so I'm asking for ideas.

Last edited by KC in S.B.; 02/17/14 11:59 am.

Down to 1 BSA, 2 Triumphs, 1 '56 Chevy
Oops,.. add 1 Sporty
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Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #528768
02/17/14 5:30 pm
02/17/14 5:30 pm
Joined: Nov 2005
Posts: 7,520
Back on the mainland!
JubeePrince Offline

Born To Run
JubeePrince  Offline

Born To Run

Joined: Nov 2005
Posts: 7,520
Back on the mainland!
I use a modern 20A blade fuse on my bike, KC...

I've blown one of them also when my original alternator stator broke up on me. It seems to be sufficient, because it blew before any fires started! shocked

Lots of people that re-wire use separate fuses for ignition system, lighting system, etc...but that's probably another thread for another day.

Cheers,

Steve


'77 T140J
"Vintage Bike". What's in your garage?

"The paying customer is always right."

Fitting round pegs into square holes since 1961...
Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #528769
02/17/14 5:30 pm
02/17/14 5:30 pm
Joined: May 2010
Posts: 2,597
Illinois, USA
TR6Ray Online content

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TR6Ray  Online Content

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Posts: 2,597
Illinois, USA
KC, I don't know about your '70 model, but here is a pre-teardown picture of my '64 TR6 which I believe was original. It had the aluminum (zinc?) tie-wraps on the frame tube as shown.

[Linked Image]

For my main fuse, I am using a 15A blade fuse. I have four sub-circuits, all of which feed through that 15A main fuse. These each are fused as follows:
  • Hi/Lo headlight circuit has a 5A blade fuse
  • Horn and stop lamp circuit has a 7.5A blade fuse
  • Boyer ignition cirucuit has a 5A blade fuse
  • Pilot, gage lamps, tail lamp circuit has a 5A blade fuse

Again, all these circuits go through the 15A main fuse. I think that is the common fuse rating for these bikes. John Healy and Stuart and others have recommended that in the past.

Ray


'64 TR6R Plus some Twins from other countries (U.S., Germany, Japan)
Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #528772
02/17/14 5:50 pm
02/17/14 5:50 pm
Joined: May 2004
Posts: 234
Left Coast
S
skidog Offline
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skidog  Offline
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S

Joined: May 2004
Posts: 234
Left Coast
That photo is the way my 72 t100r is wired.

Dave


Last edited by skidog; 02/17/14 5:51 pm.

1967 TR6R
1972 T100R
Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #528791
02/17/14 7:21 pm
02/17/14 7:21 pm
Joined: Oct 2006
Posts: 2,904
Elburn, Ill. USA
I
Irish Swede Offline
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I

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Elburn, Ill. USA
That is the way my original '70 TR6R and '72 T100R are also wired.

Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #528830
02/17/14 10:37 pm
02/17/14 10:37 pm
Joined: Oct 2006
Posts: 786
in my house
K
KADUTZ Offline
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KADUTZ  Offline
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K

Joined: Oct 2006
Posts: 786
in my house
Wires to brake switch are run as in above picture.

If you are using a stock fuse holder either a Littlefuse UK35 or SFE20.

Headlamp switch you want is a Lucas 35710. There are other switches that look like that one but are internally different. They can be used in place of the 35710 but they are wired differently.


K


1970 T120RT
1978 T140V
Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #528845
02/18/14 12:27 am
02/18/14 12:27 am
Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
KC in S.B. Offline OP

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KC in S.B.  Offline OP

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Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
Thanks for the replies ALL! I guess my brake switch wires are OK as they are then! I will move to a lower rated fuse also.


Down to 1 BSA, 2 Triumphs, 1 '56 Chevy
Oops,.. add 1 Sporty
Re: ' 70 brake switch wire secured to chainguard ? [Re: KADUTZ] #529562
02/21/14 8:47 pm
02/21/14 8:47 pm
Joined: Jun 2002
Posts: 10,261
Scotland
S
Stuart Offline
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Stuart  Offline
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Posts: 10,261
Scotland
Hi KC,

Originally Posted by KC in S.B.
I have a simple Radio shack toggle switch to power the headlight circuit at the moment. The OEM switch would be the Black flip lever I think, right?

Originally Posted by KADUTZ
Headlamp switch you want is a Lucas 35710.

31788 is also ok, works the same as a 35710.

Originally Posted by KC in S.B.
What fuse rating do you fellows recommend? The temporary 25A

Originally Posted by KADUTZ
If you are using a stock fuse holder either a Littlefuse UK35 or SFE20.

The original tubular glass fuse with metal end caps was rated at 35A. However, bear in mind that's a 'blow' rating peculiar to British versions of that type of fuse (hence - I suspect - "UK35" wink ). Every other fuse (and US versions of that fuse) are rated 'continuous', which is half the 'blow' rating. So 17.5A is the 'continuous' rating of the standard fuse; if you're using blade fuses, 15A or 20A are the nearest you'll get, ime try a 15A but carry a 20A as a spare for a while? grin

Hth.

Regards,

Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #529585
02/21/14 11:44 pm
02/21/14 11:44 pm
Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
KC in S.B. Offline OP

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KC in S.B.  Offline OP

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Posts: 4,391
Santa Barbara, California
Thanks Stuart,....... As it turns out, I ended up using a blade type fuse holder because it secured in the space better than the tubular glass fuse inline holder. I have a 20A in it at the moment. I was trying to find an accurate ammeter to test the load with engine off, but my available equipment is lacking for this job, the Fluke is only good for 10A max.. 15A blades sound a bit small, but I'll try'em and if they blow with no wire smoke, I can go up to the 20A. My wiring is 14 gage and greater.


Down to 1 BSA, 2 Triumphs, 1 '56 Chevy
Oops,.. add 1 Sporty
Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #529641
02/22/14 8:38 am
02/22/14 8:38 am
Joined: Jun 2002
Posts: 10,261
Scotland
S
Stuart Offline
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Stuart  Offline
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Posts: 10,261
Scotland
Hi KC,

Originally Posted by KC in S.B.
15A blades sound a bit small,

Fwiw, I use 'em on my T160's without any problems. smile

Hth.

Regards,

Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #529995
02/24/14 12:01 am
02/24/14 12:01 am
Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
KC in S.B. Offline OP

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KC in S.B.  Offline OP

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Posts: 4,391
Santa Barbara, California
FWIW, I spent some time fooling with the ammeter checks today. Did this with the bike on the table, full charged battery, Scorpion AGM. My intent was to see what individual devices draw, just out of curiosity. Then, key off, headlight switch/brake and tail light/Boyer enabled........ Key ON, 9Amps initial. Blow the horn, adds 2amps, for a total of 11.3 amp. Decided a 15 amp blade fuse would be a good choice! Also, 11.3 amp X 12 volt = 135 Watt. My Sparx 3 Ph stator is "susposed" to give 220Watt, so hope to be able to ride with the Headlite on and not worry about the battery going down,....... for once!


Down to 1 BSA, 2 Triumphs, 1 '56 Chevy
Oops,.. add 1 Sporty
Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #530031
02/24/14 8:30 am
02/24/14 8:30 am
Joined: Jun 2002
Posts: 10,261
Scotland
S
Stuart Offline
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Stuart  Offline
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Joined: Jun 2002
Posts: 10,261
Scotland
Hi KC,

Originally Posted by KC in S.B.
key off, headlight switch/brake and tail light/Boyer enabled........ Key ON, 9Amps initial.

Hmmm ... at a nominal 12V:-

. "Boyer" (i.e. ignition coils) should draw about 3.5A;

. "headlight" will draw either 5A (60W main), just over 4.5A (55W dip), 3.75A (45W main) or just under 3.3A (40W dip);

. brake light (21W? 1.75A) shouldn't be on normally;

. "tail light" will draw just under 0.5A (if 5W);

. don't forget the speedo. 'n' tacho. bulbs - 0.25A each(?);

. however, when working out the fuse rating needed, as well as allowing for blowing the horn, don't forget to allow for the brake lamp filament being on and any indicators flashing.

Originally Posted by KC in S.B.
Also, 11.3 amp X 12 volt = 135 Watt. My Sparx 3 Ph stator is "susposed" to give 220Watt

Uh-uh, you're falling for Sparx's dodgy 'marketing'. mad

. Electrical Watts are calculated by multiplying Volts and Amps together.

. The Sparx high-output 3-phase is a pattern copy of the Lucas RM24 high-output 3-phase.

. Lucas rated their version for 14.5A @ 5,000 rpm and 180W - i.e. Lucas used 12.4V in their calculation.

. If you look at Sparx's own "Alternator test results", you'll see they claim 14.88A @ 5,000 rpm, but this is magically transformed into 208.32W; i.e. Sparx use 14V in their calculation.

So, in comparing your "135 Watt" with "My Sparx 3 Ph stator is "susposed" to give 220Watt":-

. you're comparing apples and oranges; frown

. 14V is about where the Sparx rect./reg. will allow the Volts to rise to;

. I use Lucas RM24's regulated by twin 'matched' Zeners; 14V is about where they allow the Volts to rise to too. grin

Btw, in case you're wondering what Sparx's "Std Alt Amps" are, no one knows. shocked As you can see from this Lucas British 3-phase launch ad., they aren't figures from a Lucas high-output 3-phase alternator. Also in case your wondering, no, Lucas could not have used this ad. when the alternators produced less, Britain's Advertising Standards Authority would've dumped from a very great height on both Lucas and the publishers of the magazines and newspapers.

Originally Posted by KC in S.B.
so hope to be able to ride with the Headlite on and not worry about the battery going down

The above notwithstanding, if your Sparx alternator produces what the Sparx figures say it should, ime of the Lucas version, you and the bike'll be :bigt

Hth.

Regards,

Re: ' 70 brake switch wire secured to chainguard ? [Re: KC in S.B.] #530044
02/24/14 10:06 am
02/24/14 10:06 am
Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
KC in S.B. Offline OP

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KC in S.B.  Offline OP

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Joined: Aug 2001
Posts: 4,391
Santa Barbara, California
Well, I certainly won't be at 5,000RPM for very long, that's for sure! All considered though, my 12V x 11.3 A = 135W is still a reasonably conservative figure. I just won't blow the horn alot !! ;-)


Down to 1 BSA, 2 Triumphs, 1 '56 Chevy
Oops,.. add 1 Sporty

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