interesting starting shenanigans

[KitKat]

Hey all,

so i recently purchased a 78 gs 550 e with 9xxx original miles. The bike had been sitting for 10 years so i went through and cleaned a lot of the parts. After reassembling the bike, i went to try and start it.

The electric start would get the bike to fire, an occasionally idle for a couple seconds, then it would immediately die.

The kick start worked much better. However, it took a lot of kicks in between each start, but the bike eventually fired up and would idle for about 10 seconds then die again, all with the choke on. After going at the kick start for an hour or so, i decided to check the plugs, and they were NOT wet with gas. this confused me because the bike had been idleing before. Then when i put the plugs back in it would turn over but no firing with either the kick or electric start.


After waiting for a couple minutes, i tried the kick start again, no choke, and the bike fired, and for the first time, i got great response when i gave the gas bike and i was able to rev it and keep the bike alive for as long as i wanted. I let go of the gas slowly trying to see if the bike would idle, but it slowly went too low and died (probably just the idle adjustment screw needs tuning)

I got it to start and rev 3 times total for long periods (probably about a couple minutes each before i tried to see if the bike would idle by itself which it would for a while), and i was very happy with that progress.

But why is the bike so difficult to start? is my question, it takes numerous kicks, some without any firing whatsoever.... if this applies at all, the air filter is in terrible shape and i will be ordering a new one soon

Any input welcome.

Thanks!

 

[Steve]

Three things that are pretty much mandatory when resurrecting an old bike:

1. Adjust the valves.

2. Clean the carbs.

3. Check the points.

Any one of them will cause hard starting. Considering the bike has been sitting for 10 years, there is a good chance it's all three.

.

 

[GSX550]

For my bike, my starting troubles came down to poor spark. When I checked it was there, though admittedly not bright blue. Under combustion conditions it was not enough to start the bike. Eventually get it started and it would rev fine.

I checked a million things then put an Ohm meter across the spark plug leads. The coils secondary circuit (through the plug leads) was way over what it should be. It was out by a factor of 10 or more. I pulled the plug caps off and instead of being 5 k ohms, they were 250k ohms. Fixed that and the bike started first flick every time.

But on your bike I would also suspect the idle circuits being clogged. It doesn't take much to clog these if the bike wasn't prepped before being stored.

 

[Charlie G]

First off, congradulations on selling your old bike and the new find. I had been wondering if you had found a new bike yet. Misssed your post as to wiether you found one.
In addition to what has been said before, check that your air box is sealed up tight and your petcock is working. Keep us posted.

cg

 

[KitKat]

the petcock is fully functional and the airbox seal is fine, the airfilter will need replacing, i will get to work on checking / cleaning the points and adjusting the valves. i already went through the carburetors but i can do a thorougher job if needed

 

[BassCliff]

Hi,

CLICK HERE to see how to thoroughly clean your carbs.

Then CLICK HERE to review your "mega-welcome" complete with the maintenance lists that are pretty much mandatory when resurrecting these long-dormant GS motorcycles.


Thank you for your indulgence,

BassCliff

 

[KitKat]

is there any guide on your website Cliff, about checking and cleaning points? i couldn't seem to find it. Thanks!


edit: found it nevermind. Thanks!

 

[KitKat]

just wanted to update everyone, i checked the points and the gap was way off. after i reset the gaps to spec the bike fired up instantly and ran perfectly i was able to take it on a ride and am thoroughly happy. Thanks everyone for their input. Pictures and videos coming soon.

 

[Charlie G]

just wanted to update everyone, i checked the points and the gap was way off. After i reset the gaps to spec the bike fired up instantly and ran perfectly i was able to take it on a ride and am thoroughly happy. Thanks everyone for their input. Pictures and videos coming soon.

yahooooooo!