GT500 low speed coil

All to do with wiring, charging or just trying to figure out whats gone wrong.

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karl pa
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Suzuki 2-Strokes: GT
Location: southeast pa

GT500 low speed coil

Post by karl pa »

I lost my low speed coil again,this is my 3rd coil in 8 years.all 3 show around 120 ohms,they should be around 185 ohms,everything else in the magneto tests ok. Just wondering if this is normal, or is mine shorting them out sooner then others.I did put around 15,000 miles on in that time.
76 GT185
77 GT250
77 GT380
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73 GT550
73 GT750
74 GT750
71 T250 scrambler
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Lorenzo
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Country: Italia
Suzuki 2-Strokes: RG500 CR500 GS1000G

Re: GT500 low speed coil

Post by Lorenzo »

Karl I am not an expert on the GT500 so take my words as an input.

The continuity value for the low speed coil, should be 214 homs, not 185 (value apt to the hi speed one);

I would also check that there is a path with the capacitor on the igniter (CDI), by measuring - best with an analogic meter - that there is a little continuity, at first, soon followed by a switch to infinity, between the B/R (from the low speed coil) and the W/bl wire (to the low tension side of the ignition coil), with negative probe to the former and positive one, to the latter.
karl pa
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Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: GT500 low speed coil

Post by karl pa »

Thanks for the input, but if I am correct the low speed coil (large exciter coil) between green wire and ground is 185 ohms, high speed coil (small exciter coil) between green wire and B/R wire is 29 ohms, both coils in series between B/R wire and ground is 214 ohms.
When I installed this low speed coil, it had a value of 184 ohms, I also replaced the high speed coil, it had a value of 29 ohms. It lasted about 3 years until I couldn't start with kick starter, started right up by push start. when I checked green wire to ground I only had 120 ohms, high speed is still 29 ohms.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
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Lorenzo
Around the block
Posts: 88
Joined: Sun Nov 18, 2012 7:18 am
Country: Italia
Suzuki 2-Strokes: RG500 CR500 GS1000G

Re: GT500 low speed coil

Post by Lorenzo »

Do not want to argue and, we probably saying the same thing...

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karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: GT500 low speed coil

Post by karl pa »

I received my new primary B coil (32142-15320). Shows 185 ohms exactly. See how long this one lasts.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
gyrocfi
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Re: GT500 low speed coil

Post by gyrocfi »

I am very careful when soldering the coil in. I also use dental floss to tie the wires and coil up then coat it with epoxy. I think it helps with viberation and heat isolation. I hope this doesn't jinx me cause mine continues on after tons of miles. If the bike gets hard to start and Ive checked the plugs I will figure its the coil.
77' RD400 Stock
77' RD400 work in progess
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karl pa
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Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: GT500 low speed coil

Post by karl pa »

Installed my low speed coil today,starts right up with kickstarter. Also used your tip on dental floss and epoxy. thanks
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
karl pa
To the on ramp
Posts: 490
Joined: Sat Sep 05, 2015 3:14 pm
Country: us
Suzuki 2-Strokes: GT
Location: southeast pa

Re: GT500 low speed coil

Post by karl pa »

I lost my forth low speed coil, this one didn't have many miles on it. The CDI unit tested ok, but I decided to replace it.
This time I replaced the low and high speed coils and the CDI unit with Rexs speed shop parts, everything tested good, and after installing them the bike fired right up with the kickstart. Hopefully this solves my issues.
The parts from Rexs are advertised to be an upgrade from original, and the price is less than half what Suzuki wants.
76 GT185
77 GT250
77 GT380
76 GT500
73 GT550
73 GT750
74 GT750
71 T250 scrambler
75 T500 cafe
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