1978 Garelli Rally Sport - missing condenser

Just like the topic says. I'm attempting to swap out the condenser on my '78 Garelli Really Sport and when I popped off the magneto I noticed there is no condenser. The spot is empty, so the previous owner(s) or whoever worked on this area last just took the cables that connect from condenser to ignition ground and just capped them off with some rubber.

Now, I have put a lot of work into the bike so far - replaced the brake light resistor, cleaned and dialed in the carb, removed exhaust and cleaned the living hell out of it, etc.

It starts up perfectly, idles fantastically, mobs 30mph on flat ground.

I'm replacing the condenser because after riding for about 1 mile or 2, the engine gets hot and the bike shuts off. I've been reading around on countless forums and been in contact with Shaun from Myrons Mopeds in San Bernardino - a freaking moped guru if I do say so myself - and he has suggested swapping the old condenser out with a new one.

A cheap part and not too difficult to do. Problem is there was never a condenser in this thing.

So now I'm wondering what the hell is up with this? Anyone know if removing a condenser and then capping the ignition ground wires would be a solution or just the result of someone being lazy?

I want to get some insight on this before I start soldering the new one in and messing with the wires.

I threw some pics down with this post to give visual representation.

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Re: 1978 Garelli Rally Sport - missing condenser

Dirty30 Dillon /

I'm guessing you had/have an external condensor. Follow the wires to the HT coil, I'm sure you'll see it.

Re: 1978 Garelli Rally Sport - missing condenser

I do not see an external condenser. Or I'm not sure what it would look like.

There's a box surrounded by rubber with 2 green wires coming from it - would that be an external condensor? From what I've seen though, an external condenser would still look barrel shaped and then be attached to the frame.

The wiring is shoddy at best but has worked so far. Here's a few more photos.

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Re: 1978 Garelli Rally Sport - missing condenser

Looks like someone put an electrical capacitor inline. That would heat up and break down.

You can use any single wire condenser externally. Like for any car, and you can buy one from any auto parts store.

The wire needs to go to the positive on the coil (or spliced into the wire from the coil to the points.) And the body of the condenser needs to be grounded to the frame. Find one that has the little mounting bracket and attach that to the frame, that'll ground it.

Re: 1978 Garelli Rally Sport - missing condenser

Ok, so splice the external condenser in with the yellow wire going from points to coil or find out where the coils positive is?

How would I know where the positive of the coil is?

Also, if I do this, should I remove the inline capacitor to prevent further overheating, or will it be ok once I get the new condenser installed?

And if so, should I try to connect each corresponding cable in the junction box?

Not sure if you can see but the inline capacitor is attached to 2 blue cables (presumably rear light), a white ground and a green cable that goes to a box with shrink wrap over it which has another green cable going to the junction box.

Re: 1978 Garelli Rally Sport - missing condenser

Thats a 4 ohm white resistor not a capacitor. ^^^ Follow the black wire from the stator coils. Should go to high tension coil and then to an external condenser hidden somewhere. Here is what a stock set up looks like...

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Re: 1978 Garelli Rally Sport - missing condenser

And wtf is this??? That ain't factory...

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Re: 1978 Garelli Rally Sport - missing condenser

Live is right . That's a resistor , marked in Ohms . Ω

Capacitors are marked in Microfarads . µ

Re: 1978 Garelli Rally Sport - missing condenser

The two black wires circled come from your HT coil positive. One is going to the juntion block as you can see. The other travels into the main harness and on to your kill switch.

You need to trace back what ever wire is screwed into the adjacent terminal spot (red arrow). It should be a black wire going to the stator plate.

Any added funky stuff will be scabbed in with that.

garelliwire.jpg

Re: 1978 Garelli Rally Sport - missing condenser

i always suspect that crank seal under that stator plate, change it out so the bike dont run lean. Dont be lazy, read how to wire a external condenser.

Re: 1978 Garelli Rally Sport - missing condenser

live and P D - Thank you for the pictures and info

live- I am not sure what the box is that you circled, but yes, I can tell it's definitely not factory. One of those green wires from the unknown box goes into the same part of the junction box (screwed into the same hole) as the black cable that goes from the strator plate to the junction box and the other green cable is connected to where the resistor is - which intersects a white ground wire and the blue brake light cable.

Should I remove the resistor and the unknown box you circled in the picture?

cheetah - when you say that "any added funky stuff will be scabbed in with that." what do you mean? Do you mean that if I trace the wire back and install the external condenser will the "added funky stuff" be bypassed?

pat - I'm not being lazy but I appreciate the advice. Just trying to get a grasp on this mess lol

****Another thing I noticed is that the brake light is not wired normally like stock would be. I will include a picture in a bit here when I get a chance.

Re: 1978 Garelli Rally Sport - missing condenser

> Johnny Mueller Wrote:

> -------------------------------------------------------

> live and P D - Thank you for the pictures and info

>

> live- I am not sure what the box is that you circled, but yes, I can

> tell it's definitely not factory. One of those green wires from the

> unknown box goes into the same part of the junction box (screwed into

> the same hole) as the black cable that goes from the strator plate to

> the junction box and the other green cable is connected to where the

> resistor is - which intersects a white ground wire and the blue brake

> light cable.

That would be an aftermarket condenser. The resistor is normally found behind the brake light bulb in the tail light housing. The purpose of the resistor is to keep the motor running when the brake light burns out. The high tension coil has a ground of its own that gets redirected through the brake bulb when you pull a brake lever. When that happens it lights the brake bulb. If the bulb is burned out the motor will die without that resistor acting as the third ground point. Electricity take the path of least resistance. I will post a wiring diagram after work to better explain all that.

> Should I remove the resistor and the unknown box you circled in the

> picture?

>

> cheetah - when you say that "any added funky stuff will be scabbed in

> with that." what do you mean? Do you mean that if I trace the wire back

> and install the external condenser will the "added funky stuff" be

> bypassed?

>

> pat - I'm not being lazy but I appreciate the advice. Just trying to get

> a grasp on this mess lol

>

> ****Another thing I noticed is that the brake light is not wired

> normally like stock would be. I will include a picture in a bit here

> when I get a chance.

Re: 1978 Garelli Rally Sport - missing condenser

Long story short, electricity takes the path of least resistance. (1st) Closed brake light switch going to ground. (2nd) working brake light bulb to ground (3rd) resistor going to ground. Keep in mind we are talking about the ground path for the high voltage coil that makes the spark plug work.

Screenshot_2020-10-06-18-13-45.png

(edited)

Re: 1978 Garelli Rally Sport - missing condenser

The brake light switches are wired in "series" which means a straight line. Break or open either or both switches when you pull the lever and that ground point is broken. The next ground point is the route through the brake light bulb, which excites and there for illuminates. If the brake light bulb is burned out then the ground is found through the resistor. If you dont have the resistor then the motor will die if the brake light bulb is burned out while applying one or both brake levers.

Re: 1978 Garelli Rally Sport - missing condenser

When I say "scabbed in" I mean components that are soldered or wired into a factory harness that don't originally belong.

Yes I would get rid of both of those alien elements, the box thing and the ceramic resistor.

Then add in (scab) a automotive style condenser. This style is a self ground when mounted and the wire will then share the same terminal port as the black wire from the stator plate.

Once this is all done the bike should start but you then may have dying issues when you pull the brake levers. You will then have to start tracing the wires in your brakelight circuit to find the old problem that the PO was masking.

Re: 1978 Garelli Rally Sport - missing condenser

That factory bulletin Evil posted is the best

Re: 1978 Garelli Rally Sport - missing condenser

It looks to me like maybe the white resistor is wired correctly into the tail light wiring .

I'd insulate the connections , for sure . (edited)

Re: 1978 Garelli Rally Sport - missing condenser

Alright I finally have a chance to get back to you guys. Thanks for all the help.

Ok so here's a few images of the wiring from a different angle.

Looks like the in line capacitor (I'm assuming that's what it is) - aka shrink wrapped box with green cables - is going into the adjacent slot where the HT coil's positive goes in the junction box.

Meaning that in theory it would be wired correctly if it was an external condensor

So it seems to me someone attempted to use that as the condenser.

But there's something else weird going on here...

It looks like the resistor is wired straight to said capacitor (aka shrink wrapped box with green cables) as well as blue brake lines and then grounded by the white wire.

I will also post a few photos of the brake light.

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Re: 1978 Garelli Rally Sport - missing condenser

Jeezus. If that was my bike, I'd rip out that rats nest and start over.

Re: 1978 Garelli Rally Sport - missing condenser

Here's the brake light - dual bulb.

Looks like the grey ground wire is disconnected completely. Its folded back into the rubber on both ends. This would explain why the white ground wire is attached to blue brake wire - it is acting as a replacement to the original grey ground that should be attached to the brake light.

The green cable from capacitor (aka shrink wrapped box with green cables) in the previous photos is also attached to the white ground.

The green cable is grounded to the white because - unlike an external condenser with the mount acting as the ground - there is no built-in ground.

So just like previous suggestions all I need to do is disconnect the aftermarket capacitor (aka shrink wrapped box with green cables) completely and install the external condensor in the adjacent slot of the positive cable coming from the HT coil AND where the black cable goes to the strator.

Correct me if I'm wrong.

I'm still quite new to this and you guys are really shedding light on a solution. Thank you very much.

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Re: 1978 Garelli Rally Sport - missing condenser

> baird co Wrote:

> -------------------------------------------------------

> Jeezus. If that was my bike, I'd rip out that rats nest and start over.

You'd end up with about the same thing as is there now , but for a couple different components . Sure your condenser might look like a real condenser and your resistor might look like it's suppose to be there and both those might be in different spots , but ...

What the OP has is really not a rat's nest . It seems to be wired correctly , but for the crappy soldering .

The shrink wrapped condenser is even wired correctly , as the green/ black wire would be the ground .

I'd probably replace that , if it tested anything close to bad .

Re: 1978 Garelli Rally Sport - missing condenser

Jeezus. If that was my bike, I'd rip out that rats nest and start over.

Kind of what I was suggesting. Put the wiring back like it is supposed to be and get the proper OEM tail light mounted to the rear fender . The proper Tail Light housing and bulbs are still around just shop on Buy/sell.

That aftermarket POS tail light that you have now will not have the correct bulbs to offer the proper resistance to keep the bike running. That is most certainly why the PO built that horrific looking rats nest.

None of that mess needs to be there.

Build it right the first time and you will learn so much about what the manufacturer has intended to be a long lasting trouble free system.

Re: 1978 Garelli Rally Sport - missing condenser

I attached a new condenser, wired as instructed, and have removed the previous shrink wrapped capacitor.

I left the resistor in place (connected between both the bluetail light wire and the white ground ) as a quick test.

The bike starts and rides for a minute, can idle (poorly) but shuts off pretty quickly after some throttle.

I agree with you baird and cheetah - time to actually get this thing back to original specs.

I will try one more test without the resistor, but think I should find the correct light and throw the correct resistor. If it doesn't work with the orginal wiring then maybe I need to swap out the coil. Has new spark plug and new NGK boot.

Re: 1978 Garelli Rally Sport - missing condenser

First before starting to back up the wiring to stock. Snip that resistor where it joins the two blue wires at that solder. Then use a clean bit of wire and ground the two blues to the engine case and then see how it runs. Doing this will bypass allll the brake light circuit and give you a clean ground for your ignition. if the bike still runs the same then you can start to look at points gap timing and general fuel/carb delivery for the cause of rough operation

Re: 1978 Garelli Rally Sport - missing condenser

Moped Lar (OFMC) /

Exactly what I was thinking.

> baird co Wrote:

> -------------------------------------------------------

> Jeezus. If that was my bike, I'd rip out that rats nest and start over.

Re: 1978 Garelli Rally Sport - missing condenser

> Moped Lar (OFMC) Wrote:

> -------------------------------------------------------

> Exactly what I was thinking.

>

> > baird co Wrote:

>

> > -------------------------------------------------------

>

> > Jeezus. If that was my bike, I'd rip out that rats nest and start

> over.

Yup.

Re: 1978 Garelli Rally Sport - missing condenser

Here is the factory wiring diagram. It does not show the brake light switches or the resistor in the tail light housing. "T" stands for tail light. "G" stands for ground. "S" stands for stop (Brake) light. Put it all back to original.

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(edited)

Re: 1978 Garelli Rally Sport - missing condenser

Here is the work g diagram grom the owners manual. It shows the resistor at the tail light and both brake light switches wired in series...

Screenshot_2020-10-08-14-37-12.png

Re: 1978 Garelli Rally Sport - missing condenser

Are you digesting any of this info? Do you know your way around a multimeter? Put it all back like that diagram^^. (edited)

Re: 1978 Garelli Rally Sport - missing condenser

Thanks for the diagrams and explanation.

I will attempt to bypass the brake light today - been busy with family visiting the past few days - so I will post an update (with pics if need be) in a bit.

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