[mleek0218]

1,300 original miles, until this month, the bike hasn't been ridden since 75'.

Here is the problem:
Bike starts right up and runs absolutely perfect for about 30 mins. Once it gets hot, (I'd say normal operating temp) it loses all bottom end. It will still run normal speeds if you are cruising, but pretty much zero throttle response, and very sluggish if at a stop.

So I've torqued the head, adjusted the valves, new plugs and rebuilt the carbs. I've also adjusted the points at 3 different positions, but still the same outcome.

I've searched the net, but haven't found anything useful. Does anyone have any suggestions!?

Thanks!
Michael

[email protected]

 

[epynt1050]

Given the symptoms and the time it has been unused, I would check all the following - condenser/capacitors, coils, points, advance/retard, burnt/stuck valve, dirt in carb float bowls, vent in tank filler cap. Some are temp related, others time related (ie 30 mins).

My guess would be the condenser or coils. Have you changed the spark plugs? If not, do this as first step. Make sure you fit the correct plugs (Champion N4 or exact equivalent). Also look at replacing plug leads (wire type) and plug caps. May not be the cause of problem but new items will make life easier for the rest of system.

 

[panda]

In addition to epynts words I would say next time it happens, stop teh bike and feel the compresion on 'BOTH' cylinders. The tappet gap may be too snmall, or a valve may be sticking where it rested for all those years.

 

[stewdog68]

if intake is very hot (fuel vapor lock) also check if choke is not closed.visually make sure its opening and closing all the way(both ways)