I agree with jfc about the black. Looking at that blue wire, it looks like your meter is reading in 2K which is kilo-ohms (1000 ohms). I know it seems like it should be 2 kilo ohms but meters are like that (that means a range of 1000-2000 ohms max). So you have to multiply that reading by 1000. So .037 would be 37 ohms.
If the spark is weak after you are certain all the grounds are clean it sounds like you need to test the stator. It tells you how in the link I posted.
Possibly the stator. If you watch the 92/93 Gas Gas model video on youtube by Jim Snell he discusses that this is a common problem and the coil on the stator may need rewound. They have a tech page on how to test for it.
"Easy Start", I did see that mentioned in another post. I wasn't sure what you all called it in the UK. In the US we call starting fluid or some old timers call it ether.
Have you starting fluid?I know it's not recommended for bikes but when I have a really stubborn bike I will use it sparingly. Pull the plug, squirt some in the hole, quickly re-install the plug and kick (if it is a carb issue shooting it through the airbox won't always work). Generally if it fires with starting fluid it tells you it is not a spark issue. If it starts and dies once the fluid burns off it's either a fuel or really low compression issue. If it doesn't start at all it is usually spark related. These are just generalizations but it is a good diagnostic tool to help narrow down possibilities when you are stuck on a bike.
Also to inspect the reeds, pull the reed block and make sure the reeds are laying flat to the reed cage, check that there are no cracks or holes in the reed petals. If they are raised up or have a crack or hole they must be replaced.
I can't get that video to work, but try this. Put one plug in the bike, put one in the cap to check for spark and kick it. That way you are kicking under compression with a plug in it and the engine is spinning normal speed, not faster as they do with the plug out and no compression. This will tell you what your spark is really doing when you kick.
Trust me, you will be very happy the first time you hear it fire up after all the fiddling you've been doing. It's a great feeling. If you don't smile or laugh out loud even, I would be very surprised .
It will definitely be worth it once you get it all done! You will look back at all this and laugh about it. I have had a few doozie rebuilds over the years but now they are just fond memories of working on a nice bike.
You could try penetrating oil on any other bolts or fittings. Let it sit a few hours or overnight. I am guessing this bike was either stored outside or in a shed for all these rust/corrosion problems
This is like he end of a soap opera episode or a Daz commercial, cue Eastenders drum beat....'and on that bombshell'
More please.
Haha. I feel kind of bad he is having so many problems. I also bought a Contact 250 last week (mine is a 92, his looks like a 93 with that shiny frame). So I have been interested in things he does to his bike, but it seems every time he posts it's about a new part that is broken or messed up. I hope to read soon he got it started and it runs great. I suspect the clutch plates will be stuck after sitting that long though.
Look on the bright side, you are learning a lot of things not to do in the future when working on old motorcycles .
Just kidding, seriously I'm sorry you are having so many issues. If for some reason your kicker repair doesn't hold and you really want to her it run before you put any money in new parts, try to catch it in gear/bump start it. Find a big hill, put it in 3rd or 4th, push and jump on and pop the clutch. The downfall is if it doesn't start you have to push it back up haha.
I am picking up almost the same bike tomorrow, cool.
It sounds like you need to give the carb a proper cleaning. When bikes sit the old fuel gums up and plugs up jets and inlets in the carb. I bet once you do that it will start right up. A fresh plug is always a good idea as well after a bike has been sitting. Even after cleaning the old plug, it's usually best in my opinion to replace it.
Thanks. I am sure I will have plenty of questions once I get it back here and start going over it. I'm actually not picking it up until Sunday. I used to work as a motorcycle mechanic so I am not worried about that aspect, but I know riding a trials is a different world than the mx and trail bikes I am used. I've been watching as many basic riding videos as I can, even tight turning looks hard haha.
I was just hoping someone had one back in the day and could share some info is what I meant by interest, sorry about that .
I have always been interested in trials and figured I could start with this one playing around in the yard, etc., and hopefully next year move up to something much more modern.
But talking again with Jim Snell he said he "thinks" the bike weighs around 90kg and has a 2.8L tank.He said Gas Gas didn't digitize manuals and specs about bikes of this era. He shared some really great info I'll happily share with anyone interested, but it doesn't seem this older bike has much interest here.
Here is a good video about 92/93 bikes for anyone bored:
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My 90's Gas Gas Contact250 Project..
in Gas Gas
Posted · Edited by coop650
I agree with jfc about the black. Looking at that blue wire, it looks like your meter is reading in 2K which is kilo-ohms (1000 ohms). I know it seems like it should be 2 kilo ohms but meters are like that (that means a range of 1000-2000 ohms max). So you have to multiply that reading by 1000. So .037 would be 37 ohms.