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Hello,

I recently bought a 1983 GS450e that is having trouble starting. Basically, I have to push start it every time I want to ride it. Once I get it going it has idle issues until it is warm. If it's cold and running, I give it gas and the engine will race up to around 4000 rpms and slowly creep down to a normal idle. After it is warm it runs great. I cleaned the carbs three different times, and replaced the plugs, wires and battery. One other notable thing is that the left (driver side) spark plug is getting a little fouled with oil and the left exhaust is dark.

Any ideas on how I can make this start more reliably???


Thanks,

Marty
 

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Usually an idle issue such as yours is tracable to a lean pilot circuit and, as it gets better when the engine warms, this tends to confirm it. The rpms hanging also tends to confirm a lean situation but not 4000 rpm so I would look elswhere for that particular fault.

As your bike is fairly old other things may be causing the difficult start...has it got points? and are they set correctly. Check if there is any arcing at the points this indicates a condensor is on the way out.

If it doesn't have points then other areas to suspect are caps cables and coils in that order.

As it is difficuolt to start the battery may not be getting any or much charge. To check this run the engine and, using a multi meter set to 20 VDC, check across the battery terminals.

You should read about 13.5 to 15 VDC at around three to five thou rpm.

If you are using an electric start it may be taking all of the current and leaving very little for the ignition. Try a plug out test...you need a nice fat blue to white spark anything less is suspect.

You will probably have to check all wiring for shorts, chaffing, loose/corroded connections, and faulty switches...can of WD40 is good for squirting into these.

What is the state of the air filter...I know that many reckon that, on CV carbs especially, less air means less fuel. While this is OK in theory in practice it rarely comes out that way...even normal slide carbs will pull less fuel at idle if the air filter is clogged but you still get a rich setup...albeit caused by the cable pulling the slide up as apposed to vacuum doing it.

Finally what is the state of the exhaust...if it is clogged up then it will be difficult to start....mufflers can deteriorate to the point where rust collect in quantity and prevents the motor from running until at normal idle speed.

All too often it is carburation that is blamed for a poor running engine when there are other problems.

Having said that I would start at the carbs and make little adjustments. The hanging idle may simply be stiff cable, inccorect routing ,or stiff carb linkage

Good luck
 
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