[scooter man]

1980 cx500 cafe racer, this has happened a few times, when ridden about 1/2 mile the bike stalls, then there is no response from the start button for about 30 seconds, then it kicks back in and starts. had this bike 2 weeks, I don't have a clue where to look, could it be the ignition switch? any ideas?

 

[reclinedrelic]

Does the bike still have the stock wiring harness? When the bike stalls and the start button is unresponsive are the headlight and the instrument light (oil pressure and neutral lights) still illuminated? Check that the main fuse is OK. Check that the harness plug is properly installed into the socket on the key switch.

 

[scooter man]

no has no neutral or oil pressure lights, has aftermarket speedo, yes the headlight and speedo lights are still on.I had it running on the center stand today and in never stalled, The harness is in properly.

 

[Sidecar Bob]

Ah, the joys of owning someone else's "project". I can't help feeling that your problem may be related to something in the electrical system that the Previous Owner changed and not knowing what they changed makes it very difficult to figure out what is causing this problem. It is even hard to tell where to start looking.
Does the bike still have the original type fuses or did the PO replace them with some sort of self resetting circuit breakers? (that would explain it coming back to life after sitting for a while).

Maybe you could remove the seat, side covers (if it has them) and tank and take some pics that show the wiring & electrical system. Pics that show the headlight (original or changed?) and any wiring in or behind it might help us figure out how far any modifications to the electrical system have gone too.

BTW: This would be a very good time to add your bike's original model and model year and your location to your profile as I asked you to do in the first 2 threads you started. There are some significant differences between the models and years and the climate where you live could affect things like this.

 

[scooter man]

rode it yesterday, let it warm up in the garage for 10 min. never stalled at all, it was 40 degrees out, buy the way does the fan run all the time or only when it gets hot? I thought I read where is was driven off the water pump.

 

[CXPHREAK]

The stock 500 fan runs on the front of the cam - so yes, it runs all the time that the engine is running.

 

[scooter man]

thanks for the answer, what would be the lowest temp. that it would be safe to start a cold engine? when I put the chokes on it revs quite high, it has murrays carbs on it and I don't see anyway to adjust the fast idle.

 

[CXPHREAK]

Those chokes aren't actually chokes in the traditional sense but they are still cold start enrichening devices - they just work a little differently.

Unlike a choke the bike can't be ridden with them in use.

I have them on some bikes.

I generally use one to start and close it almost immediately while opening the other - which is also closed after a couple of seconds and the bike is left to idle while I put on my helmet etc..

There is no way to adjust the fast idle.

Lowest temps to start? I couldn't tell you. Temps don't get low enough here for it to be a consideration.