[ann]

Hi I have an old bike that runs off a points system, old school stuff. I'm curious if a blown fuse that connects into the ignition switch would prevent my bike from starting, or getting a spark to the spark plug. I know these old bikes can run off of just the points and magneto, just wondering if a blown fuse might be why it isn't starting.

 

[Unkle Krusty]

Remove the plug and check for a spark. If none, replace the fuse and try again. Does the bike have a battery?

UK

 

[SemiFast]

Soooo ...... what bike is it?

Might help in getting you good information if the guys/gals know what bike we're talking about.
Also more info about the fuse.

 

[slumlord]

https://bikez.com/motorcycles/kawasaki_kh100-b7_1976.php

According to the avatar, this one.

 

[ann]

Fuse is a 15A, it has a battery, 6V, 76 Kawasaki KH100. No spark from the plug with the fuse intact either, I'm thinking it's a timing problem with the points.

 

[hogcowboy]

Fuse is a 15A, it has a battery, 6V, 76 Kawasaki KH100. No spark from the plug with the fuse intact either, I'm thinking it's a timing problem with the points.

Okay, back up some. Was this bike running or are you trying to get it running for the first time since you acquired it? As in restoring a bike that was parked long ago.

I'm just wondering if you might be better off converting to 12v but probably need to get it running with 6v first anyway. Yes, timing could be off but you should still get spark somewhere along the line if I'm not mistaken.

Just curious, have you ever given it a shot of starter fluid or carb cleaner when you try to start it? It certain sounds like it's an electrical issue but was just wondering here.

 

[Unkle Krusty]

You need to start at the battery. Should have at least 6.25 volts. Keep checking for volts downstream, at the fuse, after the fuse, at the ignition switch, after the ignition switch, all the way to the points. Do not forget the kill switch.
Something I do not know about your bike: Does it need a battery to run, or is it a true magneto which does not need a battery. I am assuming it needs the battery.
Did it run for you previously as HC has asked?

UK

 

[ann]

The bike was running it was starting up really well. But After a few times kicking it over it decided not to start again. I used a tester on the ignition coil and I was getting good spark directly out of the ignition coil cap that goes over the spark plug, but no spark out of the plug directly. On the bike wiring schematic it needs a battery, but I've been told it can run purely off the magneto points- I'm just so new to all this I'm not sure. I just didn't know if a blown fuse might be the reason I'm not getting spark out of the spark plug?

 

[ann]

I'm a little discouraged because I had started my bike, it was running good and then all of a sudden a bunch of things happened, my battery died, fuel stopped going to the carb, the fuse blew and I stopped getting any spark out of the plug and I wasn't getting that usual clanky noise when I was kicking it over.

 

[cmonSTART]

Welcome to vintage bikes! Really, welcome - that's a nice bike you have!

Work on one problem at a time - you will get through it!

Personally one of the first things I would do is to clean and adjust and/or replace the points. They need routine cleaning and adjustment and are often the cause of lost spark issues. It's not difficult once you have done it a couple times, and a shop manual is very helpful getting you through it the first time.

 

[ann]

Thanks, I really like it. I've replaced the points once already as well as the condenser, do you think it might be a problem with the big internal coils around the points? That magnetism just isn't happening?

 

[cmonSTART]

It could be. Kawasaki likely has a test procedure for it as well as the coil - you'll need an ohmmeter most likely.

Another idea is to go through the system and check all of the electrical connections and grounds associated with the ignition system - similar to what Krusty suggested.

 

[Unkle Krusty]

Also try another plug, in case the one you are using has fouled. If it is an NGK, I am guessing it is about a number 8. Try a 7 for testing purposes.

UK

 

[ann]

I will try it out. I think I may have found something else- If my flywheel key was broken would that cause an offset with timing? I can still put the key in the hole, and throw the flywheel on top, I"m just curious if it's loose inside that hole would that cause timing to be off?

 

[cmonSTART]

Absolutely! I used to work on a lot of forestry equipment and that was a major issue we would run into on chainsaws from time to time. It will definitely cause a problem.

You'll have to replace the key - just resetting the flywheel will not be enough. There's enough "jerking" when the engine runs to move the flywheel again within a few seconds of running.

Good find!