Engine Conks Out. Overheating?

[Anonymous]

I just picked up a 1978 GS400 twin, I think it may be an "E" model (by the way, where do I check for that?)
It runs great, starts right away and idles perfectly. However, it seems to overheat under various riding conditions, in traffic, on the highway, just riding around. The engine seems to run very hot and then it starts to run rough and dies. Sometimes it needs to sit for a while before it will start again.
The one thing I'm most concerned about is that the previous owner's mechanic had replaced the ignition unit (was it a CDI?) with a Honda points system. Not sure why, and not really sure what the details are about it. I have the work order from the shop that shows it was replaced by a Honda points systems and that's it. Could this be causing the problem? It runs great most of the time.

Also, anyone know where I can get a shop manual for my 1983 Katana 750?

 

[SqDancerLynn1]

I would check the ign timing, If the timing is incorrect it could cause it to overheat You should also check the spark plugs and make sure it is not running to lean which could also cause it to overheat definately NOT good
you could end up seizing the engine if the problem is not fixed. It sound like it is already trying to seize when it gets hot. 78 GS would have had points installed originally. Keep checking on ebay for shop manuel

 

[Anonymous]

There is no E model GS400 for '78 only a C or an XC. XC is kick start only, C is electric and kick. Both bikes look alike other than color. I believe the E models came later and meant the bike had mag wheels.
Axel

 

[Anonymous]

If it is overheating, when it stops running, is the engine not turning over with the starter until it cools. An air cooled engine could seem to be running hot, because they are air cooled. It may be that the engine is fine, but some component is failing with the normal increase of heat that occurs.

I'd check the aforementioned items for sure, but if it runs with this set-up, it's probably not the set-up per se, but something that is failing due to heat.

But I guess my question is: Does it actually seize the engine when this happens. If yes, then don't ride it until you get to the bottom of it or you'll be tearing more apart than you care to.

Roger