Layne Posted October 7, 2023 Report Share Posted October 7, 2023 I bought a new 1992 Gas Gas GT25 Contact with the hydraulic clutch back in 1993. I still have that bike and I have been fixing it up to sell. After all the work I did I found out it has no spark. I put a new plug in it and disconnected the kill switch, still no spark. There is a picture below of my coil and electrical components without the gas tank on. I'm not sure where the black kill switch wire goes to. It goes from the handlebar to a green clip type plastic box. This box plugs into a second half of another box. See the attached picture. I'm kind of lost with these wires. I'm not sure where it continues to go from there. I removed the coil and replaced the coil spark plug boot and I think I am getting somewhere. I bought a digital multi meter to trace down continuity circuits. This wiring stuff is very confusing to me. What do I look for next? Help Please. Quote Link to comment Share on other sites More sharing options...
lineaway Posted October 7, 2023 Report Share Posted October 7, 2023 The cdi box on those would go bad. Very common. So what country are you in? Quote Link to comment Share on other sites More sharing options...
reggie Posted October 7, 2023 Report Share Posted October 7, 2023 The CDI box for this bike is p/n M04016000 there is a black wire that comes out of the CDI that is supposed to be connected to a chassis ground. I do not see your CDI box in this picture. to the best of my memory the CDI box is approx. 70mm long x 15mm x 15mm there are 2 x 3 wire connectors going to it, one on each end. Good luck. 1 Quote Link to comment Share on other sites More sharing options...
Tr1AL Posted October 7, 2023 Report Share Posted October 7, 2023 @LayneThere are wiring diagrams on www.thehellteam.com site under Tech support GASGAS INFO - thehellteam. Quote Link to comment Share on other sites More sharing options...
lemur Posted October 7, 2023 Report Share Posted October 7, 2023 Is easy: The silver box is the regulator and the red box is the rectifier, both of those relate to powering your fan which required DC voltage. The fan will also have a thermostat switch so the fan only turns on when it gets hot. Your ignition parts consist of an alternator which produces AC energy to power everything plus a sensor to know where the piston is, both those items are inside the engine casings, attached to the CDI black box that initiates an electric charge to the ignition coil which intensifies the voltage from the CDI box so that it can make the plug spark 🤓 Good start would be clean and reconnect all the connections to everything including the ground wire which you can ohm meter test, then try for spark again. If it comes to meter testing I would always start at the source of the power which is the alternator output, service manuals will tell you how. The coils and ignition wires can be ohm meter tested but the CDI box would need to be swapped out with a known good one to know for sure if you need a new CDI box. Quote Link to comment Share on other sites More sharing options...
Layne Posted October 8, 2023 Author Report Share Posted October 8, 2023 (edited) 8 hours ago, lemur said: Is easy: The silver box is the regulator and the red box is the rectifier, both of those relate to powering your fan which required DC voltage. The fan will also have a thermostat switch so the fan only turns on when it gets hot. Your ignition parts consist of an alternator which produces AC energy to power everything plus a sensor to know where the piston is, both those items are inside the engine casings, attached to the CDI black box that initiates an electric charge to the ignition coil which intensifies the voltage from the CDI box so that it can make the plug spark 🤓 Good start would be clean and reconnect all the connections to everything including the ground wire which you can ohm meter test, then try for spark again. If it comes to meter testing I would always start at the source of the power which is the alternator output, service manuals will tell you how. The coils and ignition wires can be ohm meter tested but the CDI box would need to be swapped out with a known good one to know for sure if you need a new CDI box. It looks like this Motoplat Ignition Module 406 is what I need. This is what was on my bike behind the regulator and rectifier and it looks like this is what was used before they started using the CDI at Gas Gas. See the wiring diagram for my bike below. I looked all over the internet tonight and couldn't find this motoplat modul anywhere. Where on this earth can I find this Module? Anybody know? Edited October 8, 2023 by Layne Quote Link to comment Share on other sites More sharing options...
lemur Posted October 8, 2023 Report Share Posted October 8, 2023 Motorcycle scrap yard that has small displacement euro bikes would be the best source for replacement. You can find an example wiring diagram for the internals of the CDI module if you google up "motoplat CDI wiring diagram" images. Quote Link to comment Share on other sites More sharing options...
lineaway Posted October 8, 2023 Report Share Posted October 8, 2023 Probably Rising Sun, but Jim Snell passed away last week. Not sure if anyone is taking over his business. Quote Link to comment Share on other sites More sharing options...
majesty Posted October 8, 2023 Report Share Posted October 8, 2023 1 hour ago, lineaway said: Probably Rising Sun, but Jim Snell passed away last week. Not sure if anyone is taking over his business. That's very sad news........ Quote Link to comment Share on other sites More sharing options...
Layne Posted October 9, 2023 Author Report Share Posted October 9, 2023 11 hours ago, lineaway said: Probably Rising Sun, but Jim Snell passed away last week. Not sure if anyone is taking over his business. wow that's a shock that Jim from Rising sun passed away, God Bless Quote Link to comment Share on other sites More sharing options...
Layne Posted November 9, 2023 Author Report Share Posted November 9, 2023 On 10/7/2023 at 8:22 AM, lineaway said: The cdi box on those would go bad. Very common. So what country are you in? U.S.A. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.