GT500 Very hard to start

[wvc]

I have a 76 GT500 I'm starting a restoration on. Before I start tearing it down, I wanted to get it running good to see if there were any issues that need addressed. I cleaned the carbs, new battery, new air cleaner, new plugs, and it runs good. But its VERY hard to start. Cold or Hot. Once running it runs great though. Set the plug against the head, and it looks like the spark is very very weak, if any at all.

The GT500 has the PEI electronic ignition. My guess is the stator coils that provide the voltage to the cdi, might be getting weak and don't provide enough voltage for easy starting, but once running the rotor is spinning fast enough to provide good voltage to keep it running. Any other thoughts or suggestions. I also just bought a used ignition coil off ebay to see if that helps at all.

Anyone know where to find GT500 ignition parts at a reasonable price? Suzuki still sells some of the stuff, but prices are outrageous, especially if you don't know exactly which part is bad.

[ericsattic]

I might get criticized for continually recommending Paul Miller, but he does have some hard to find stuff in great condition, and has lots of other parts not even listed for sale on eBay (just give him a phone call). Here is his web page and one part he has so you know who he is and how to contact him

http://millersvintage.com/" onclick="window.open(this.href);return false;

http://cgi.ebay.com/ebaymotors/Suzuki-G ... ccessories" onclick="window.open(this.href);return false;

[tz375]

The amount I know about GT500s could be written on the back of a small stamp, but I thought there were a couple of people offering replacement CDI including that UK TITAN site.

I'd start with a good (tested) coil and new plug caps and plugs and then clean up the kill switch contacts (the problem 99% of the time) and all the other electrical connections.

[wvc]

Thanks for the tips. I have a used coil on the way, and will try that first. The kill switch works properly when the bike's running, so I don't think thats it. I'll look into the UK Titan site, hadn't heard of anyone selling an aftermarket cdi before, but I did see the post where someone had a homemade CDI.

I've bought several things from Paul Miller already for the project, but I've noticed some of things he sells are just new suzuki parts marked up, which would probably be the case on GT500 stator coils, since suzuki still sells them new. I'm still leaning towards those stator coils being the problem, just wish I knew if there was a way to test them first before buying new ones.

[rbond]

I am the fellow with the home made CDI. I think your stator coils are going bad. Mine (original) lasted a year from when I bought the bike, replacements about a year and a half. Maybe it's me but that was too short. I may have not had something connect good enough and ruined the coils? Any way, replace all three coils, and this is very important, cover all the soldered connections with EPOXY. If you don't, the wires WILL vibrate off. I got very good at popping the flywheel off in less than five minutes till I learned that lesson. Also you can replace the ignition coil with one from Dyna S (DC6-1) for half the price of a new OEM and probably get a better spark. Good luck and let us know how you are coming along with the bike.

[oldjapanesebikes]

I've bought several things from Paul Miller already for the project, but I've noticed some of things he sells are just new suzuki parts marked up, which would probably be the case on GT500 stator coils, since suzuki still sells them new.

Yep - if you see a bar code in the ad, then its probably still available directly from Suzuki. What you do see are country variations - some parts might be available from Suzuki in Canada but not in the USA, and also the other way around.

I'm still leaning towards those stator coils being the problem, just wish I knew if there was a way to test them first before buying new ones.

Take a look at this link.

[wvc]

Thanks for that link. Lots of good info, and gives me all the measurements needed for testing the individual components. I think I've been to that site before in all my gt500 internet searches, but had forgotten about it. Bookmarked now. It also suggested trimming a 1/4" from the spark plug leads to get rid of the worn out area, to help with weak spark. Hadn't thought of that either, but I'll give it shot.

In theory the PEI ignition seems like a great idea....bike keeps running even with a dead battery. But it seems to have many weak spots. Anyone know if suzuki used this style on any other bikes?

[tz375]

If it's the stator, there are a couple of places that can rewind them or sell a replacement. I haven't checked Electrexworld in the UK, but they know their stuff and may have a replacement.

I had a Hitachi coil rewound by a guy out in Colorado and another done by a guy in Australia for TZ race bikes when the low speed coils went bad. It's not too expensive.

[dinogt]

Sometimes....often...the cylinders and the top cylinders and the coil plate and the crankcases are too rusty and the electricity does not go through so , the spark can't be in the spark plug...

[oldjapanesebikes]

Sometimes....often...the cylinders and the top cylinders and the coil plate and the crankcases are too rusty and the electricity does not go through so , the spark can't be in the spark plug...

Good point - checking the grounds is always a good first step.

[wvc]

Got 'er figured out. I bought a used ignition coil, and that of course didn't help anything.....but I've got a spare now. I ordered the 2 stator "primary" coils new from Suzuki. About $50 each. Tested the coils per the specs in the above webpage, and the Low speed coil (the big one) was only 100 ohms, and was supposed to be 185 ohms. The hi-speed coil was right on at 30 ohms. So I just changed out the bad low speed coil, and left the original hi-speed. Put it back together, and got a nice big FAT blue spark. I was happy. Put some gas to her, and she fires right up now, first kick everytime.

Thanks for all the help again guys. Now time to start tearing it down, and going thru all the pieces, and try to make her look like new again.