A3 70cc Even Bogging to death once reaching hot temps.

Conor Stratton /

Really looking for some direction here,

Silver Bullet I kitted with a 70cc A35, side bleed pipe, vm 18 carb.

What’s happening is the bike runs absolutely perfect and then about 10 minutes in (once the engine is at max heat) it bogs evenly and quickly to dead. Won’t start again until it has cooled.

It has been checked a million times for air leaks in the usual suspect areas, all good.

It started with a 70 jet in the kit and was too lean. Went to 85, too rich, back to 80 too rich, back to 75 and I think it’s good there. Weird thing is that whether the plug was reading rich or lean, it made no impact on the issue. As in it didn’t take more or less time running the bike before it died the same way / had the same problem.

I had lost my air filter (Fell off on a ride not sure where) but had rejetted since, I just got replacement airfilter so that’ll be one thing to test.

I’m not sure that I soft seized, I was told I probably didn’t, but I’m at a loss here with ideas and things to check for.

One thing I’m thinking is that if the engine head wasn’t torqued enough, the expansion of the gasket between head and cylinder could be air leaky from the heat once the engine is fully hot. But idk if that’s sound or not.

Appreciate any advice here.

Re: A3 70cc Even Bogging to death once reaching hot temps.

Replace the condenser , externally mounted .

Re: A3 70cc Even Bogging to death once reaching hot temps.

when it dies...immediately check for spark.

Re: A3 70cc Even Bogging to death once reaching hot temps.

Conor Stratton /

Are you thinking if it loses spark then it could be timing? Just looking for what to do next if that’s the case, thanks!

Re: A3 70cc Even Bogging to death once reaching hot temps.

Conor Stratton /

Will check on that thanks!

Re: A3 70cc Even Bogging to death once reaching hot temps.

> Conor Stratton Wrote:

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

> Are you thinking if it loses spark then it could be timing? Just looking

> for what to do next if that’s the case, thanks!

Just replace the condenser . Condenser has nothing to do with timing , only making spark .

Re: A3 70cc Even Bogging to death once reaching hot temps.

♣Slew Foot♣ /

Crack in float.

Re: A3 70cc Even Bogging to death once reaching hot temps.

Conor Stratton /

Was looking at it today and noticed it’s missing that screw there, any chance that could be causing it to fail or probably not? Just wondering before I order the new one. Attached pic below.

1F03D8E1-E4D0-4297-A3DE-62A977D51894.jpeg

Re: A3 70cc Even Bogging to death once reaching hot temps.

open it up and pull that screw outta there, or find the bits. might be helpful to tighten all the others in there and check for damage. look up how to take a flywheel off, flywheel puller, do I need a flywheel puller, how to set points, and how to service points and flywheel crankcase seal. then report back with pictures.

Re: A3 70cc Even Bogging to death once reaching hot temps.

Pushrod Fifty /

That looks like the condenser mounting screwhole? If the condenser is loose, it wont make electrical contact to ground. I would replace with a new external one.

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