Mystery idle problem

I am having this odd idle problem. Only happens sometimes, seems to be getting more and more frequent. Generally, after blipping the throttle 10 times it will take off and run fine when going higher speeds. Come to a stop, starts doing this again, takes forever to take off again. Sometimes, it won’t move or change no matter how much gas I give it. Leaving me stranded.

1977 Garelli ssxl NOI. 70cc kit, new petcock, fuel filter, new 15mm bing carb, (it also did this with the old carb but not near as frequently), 78 jet.

I feel like it’s a fuel supply issue but I’m running out of ideas. Please help!!

Video link below with the issue

Re: Mystery idle problem

Josiah Radebaugh /

Have you checked for air leaks?

Re: Mystery idle problem

I have not yet. I don’t even know how todo that. That’s something I’ve been a little worried to tackle. How hard is it?

Re: Mystery idle problem

This should be in repair forum.

That sounds like an ignition problem.

Crank seals are 42 years old unless theyve been changed. It just does not sound or act like seals though.

Do you have a conventional 12 volt automotive timing light laying around?

Get one.

Park moped next to car and hook up timing light power leads to car battery. Hook up inductance lead to spark plug wire near plug on Garelli. Start Garelli and pull trigger on timing light. Watch light and see if it flashes intermittently while its running rough. You obviously got to do this while its acting up so plan ahead and have the timing light and car ready.

Let me know what you find.

Re: Mystery idle problem

Where did you get the intake from treats? Which one? Is it a 15mm intake?

Re: Mystery idle problem

Check your spark plug wire and cap and don't run a resistor plug or cap...also check the ground wire and points wire on coil ........

Re: Mystery idle problem

> live ɘvil Wrote:

> -------------------------------------------------------> > Watch light and

> see if it flashes intermittently while its running rough.

To be clear; you will be looking for the light to stop flashing intermittently as the motor stumbles @ idle.

Re: Mystery idle problem

Yeah its a Malossi Filter. Link below if you want to get one. It is NOT 15mm. I was having trouble finding a 15 mm that wasn't running into my front tire. So I got this one because it was high flow, short and 90 degrees. I had to retro fit where it connects with making a grommet for it by using High temp electrical tape. Not easy and it's not 100% correct yet. Still working on that. It's jank but it works. nice filter tho.

https://www.treatland.tv/malossi-PHBG-RED-air-filter-E8-p/malossi-phbg-e8-filter-046199.htm

Re: Mystery idle problem

I don't have a timing light. I plan to dive in deep again tomorrow night. If it get to try your method I will let you know how it goes. Thanks for the insight.

Re: Mystery idle problem

Have you ever messed with the wiring harness coming out of the engine case from magneto? Moved it or re routed it?

Re: Mystery idle problem

Dude you cannot use electrical tape as a shim.

Re: Mystery idle problem

> Daniel '' Wrote:

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

> Dude you cannot use electrical tape as a shim.

Sure he can . It'll work until it starts slipping out of place and then more trouble than it's worth .

Re: Mystery idle problem

I said it works. I did say how great it works, but does work... for now.

Re: Mystery idle problem

I had that with a loose muffler

Re: Mystery idle problem

> Aaron Turek Wrote:

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

> I said it works. I did say how great it works, but does work... for now.

Question:

How long has "now" been?.....

Since you did that?

Re: Mystery idle problem

.... since Saturday. It already slid out.. what’s a bro todo?! Buy a filter that actually fits?! That would be too easy.

Re: Mystery idle problem

chillywillie - ya know - I had buddy suggest the same thing. maybe if the back pressure isn't right then it will run all funny. I have another stock pipe laying around that i could try to see what it does. (edited)

Re: Mystery idle problem

bring that junk over to my house i'll get you set straight.

Re: Mystery idle problem

maybe tonight?? If it doesn't downpour

Re: Mystery idle problem

> Aaron Turek Wrote:

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

> .... since Saturday. It already slid out.. what’s a bro todo?! Buy a

> filter that actually fits?! That would be too easy.

On filter side of carb?? Not intake side?

That shouldnt make much difference except possibly loosing a filter.

Id definitely take the opportunity to go meet Graham. (edited)

Re: Mystery idle problem

After a month of headache - this thing is finally running right. I want to summarize what we did for anyone else that runs across this.

*Air leaks*

I took it to Grahams place where he very quickly diagnosed an air leak at the head gasket and at the base gasket. The base gasket was still baked on there from when i swapped the 70cc kit on. So we spent over an hour shaving it off with an exacto knife. We cut a new base Gasket and ordered a new head gasket. After installing those, it then didn't want to even start.

*carb work*

It took several weeks for it to dawn on me that now the Air to fuel ratio's were all out of wack now that there was no air coming in from the leaky gaskets. So after messing with it i could get it to start but it would not idle to save its life.. I changed the jetting up, raised the jet needle to the highest setting, I then even had to adjust the screw at the top of the carb where the throttle cable comes into the carb to raise it a touch more and boom. She finally runs. I couldn't believe how fine tune those adjustment to the carb were. holy balls.

Now I'm going to go ride til the head melts off.

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