Aftermarket Coil

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Vintageman
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Aftermarket Coil

Post by Vintageman »

For Suz twins, T350/T500 for example and with points what is a good aftermarket coil (singles or set)?
By good I mean maybe a little more output power (voltage) for plugs, Easy to install : it fits mechanically in place, and to be real fussy has the right connector ends (if not OK).


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Vintageman
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Re: Aftermarket Coil

Post by Vintageman »

does this fit the criteria?

http://www.hvccycle.net/suzuki-gt380-gt ... 410-31010/" onclick="window.open(this.href);return false;
Current Bikes
74 GT250 (T350 upgrade),
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77 Yamaha RD400 (Daytona Cyls),
pearljam724
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Re: Aftermarket Coil

Post by pearljam724 »

Measure the distance between the mounting holes on the coil. Find out what ohms the factory coils are. There are dozens of aftermarket coils on EBay. As long as distance between mounting holes and ohm rating is the same. They will be as good or better than the originals. I wouldn't install coils with a larger ohm rating on these bikes. You'll have to make your own electrical connector which is a piece of cake using your original connector on one end and spade connectors on the coil end. There are Asian coils listed all over eBay at 1/5th the cost that other people sell them for. I have them on my 750 and they work great. My bike fires quickly. There are 2 types of coils. Single tower and twin tower. If your bike has separate coils for each cylinder. You'll need single tower coils, obviously.
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jabcb
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Re: Aftermarket Coil

Post by jabcb »

I’ve used coils from Rex Caunt Racing on a few bikes. Took a look at eBay & there now several different alternatives.
Rex Caunt coils are cheap but they are in the UK, so shipping will take longer.

80mm mounting centers & ~4 ohm primary is correct for the T250/T350/T500 & early GT250.
So the coils in your link should be fine.

For best results, use either: resistor caps & non-resistor plugs, or non-resistor caps & resistor plugs.
Fine-wire plugs will also help a bit because they fire at lower voltages.

There is also some benefit from correctly wiring up the coil primary.
(It works when you reverse the primary wires but requires a bit more secondary voltage to fire the plugs.)
The coils in your link have proper color-coded primary wires, which makes this easy to figure out.
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

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Vintageman
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Re: Aftermarket Coil

Post by Vintageman »

jabcb wrote:There is also some benefit from correctly wiring up the coil primary.
Good point and probably would have forgot... I think if you have it backwards the electronic flow the wrong way at the plug making it wear faster (tab material wears) and little harder to get them to emit off tab versus electrode (the material surrounded by ceramic insulator). I am going to order a set and I'll you guys know how it goes. I am lazy and those look like they plop right in and OEM fit?
Current Bikes
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
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akendall1966
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Re: Aftermarket Coil

Post by akendall1966 »

Running these:
http://www.ignitech.cz/en/vyrobky/accessories/ic/ic.htm
Ignition coil IC-TCI-S (about half way down the page)

They are not handed like the OEM, so are a little tight on the tank on my T500-III, found best fit is to turn one around and route the HT lead back under the coil. Can't comment on if they produce higher voltage spark.
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tz375
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Re: Aftermarket Coil

Post by tz375 »

Here's a set of three of those coils on a GT750 bracket. I suspect that they may be the same coils that Rex Caunt and others are selling, but I had an order in for a multi channel programmable ignition so might as well buy coils at the same time.

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jabcb
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Re: Aftermarket Coil

Post by jabcb »

Info on how I installed the Rex Caunt coils on a GT750:
viewtopic.php?f=29&t=4824&start=1
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more

Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
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Re: Aftermarket Coil

Post by pearljam724 »

tz375 wrote:Here's a set of three of those coils on a GT750 bracket. I suspect that they may be the same coils that Rex Caunt and others are selling, but I had an order in for a multi channel programmable ignition so might as well buy coils at the same time.

Image
I agree, Richard. No ill will toward Rex Caunt. Rex Caunt claims to make their own coils having spoken to them. I have difficult time believing that. Other sellers sell the same exact coil at a much cheaper price. Appears that way to me. From my experience. They are exactly the same. Does yours have male spades attached on the other end ?
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tz375
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Re: Aftermarket Coil

Post by tz375 »

I meant no disrespect to Rex Caunt. He and hi staff are very helpful enthusiasts.

AT the other end of the coils there are two spade terminals marked + and - .
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Alan H
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Re: Aftermarket Coil

Post by Alan H »

Just fit genuine coils and non resistor plug caps, or just make sure all connections between battery/coils/points are clean and OK and genuine NGK plugs.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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