77 GT 750B plug caps resistence ?

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T350guy
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77 GT 750B plug caps resistence ?

Post by T350guy »

Today I washed the bike after a ride down a very muddy road.
When I started the bike it ran only on the LH & RH cylinders, the center was shorting out.
I decided to check the Ohms on the caps ( steel casing type ) and they were..9..11 and 12.
I know some Suzuki 4 wheelers ran 10 Ohm's caps but is this normal for an old Suzuki to run high Ohms Caps on a point system?.
I Installed 5 ohm caps I had as spares.

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Re: 77 GT 750B plug caps resistence ?

Post by GT750Battleship »

:up: Hi,Ian I'm sure the caps are around 5 ohm,checked mine a little while ago,when I suspected a dud coil ! I'm sure I got 5 ohm at the cap as a reading !!!
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Re: 77 GT 750B plug caps resistence ?

Post by T350guy »

Thanks as I wasn't really sure on what Suzuki caps were on the older bikes.
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Re: 77 GT 750B plug caps resistence ?

Post by oldjapanesebikes »

That would be 5K ohm eh ? Not just 5 ohm. A long time ago I wrote a bit about caps, plugs and leads at this link:

http://www.oldjapanesebikes.com/gt750/g ... _and_Leads" onclick="window.open(this.href);return false;

8)
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T350guy
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Re: 77 GT 750B plug caps resistence ?

Post by T350guy »

You are right Ian..5k it should have been..Guess it's an old habit but almost everyone in the shops just call them 5 ohms..
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Re: 77 GT 750B plug caps resistence ?

Post by Suzsmokeyallan »

As an exercise in seeing why caps die I've opened some caps and serviced them, so they can be taken apart. I posted the thread below a while back about this. The cap itself wont fail unless its fractured, its the parts inside that get corroded or the resistor that goes out of value.

viewtopic.php?f=29&t=5094&p=110045&hili ... ps#p110045" onclick="window.open(this.href);return false;
Two strokes, its just that simple.

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Re: 77 GT 750B plug caps resistence ?

Post by T350guy »

Allan I took mine apart in trying to save the original steel cover style caps. The resistors are shot BUT even after inserting a stainless insert I cannot get a reading now on any of them. Must be something to do with the spring at the bottom that touches the screw end for the HT wire.

Haven't tossed them..will have another look at a later date.
I do believe it must be corrosion down there but they seemed to be a little hard to remove..
A winter project

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Re: 77 GT 750B plug caps resistence ?

Post by Suzsmokeyallan »

Yup you've got more continuity issues there, I had about 12 caps and I resurrected six of the best for two bikes. In the pile of resistors two were out of tolerance so those parts can fail.
You should use a piece of brass rod to replace the resistors, and make sure the springs are clean and in good shape where they contact it.
Two strokes, its just that simple.

69 Suz U70
69 Suz T500
72 Suz GT750 cafe
74 Suz TS250
74 Suz GTXVR project
75 Suz RE5
75 Suz GT750
76 Suz TS400
76 Suz GT750
81 Suz GSX1100
86 Suz RG500x2
88 Hon CR500
93 Hon CBR900RR
98 Suz GSF1200x3
15 Kaw Ninja H2
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