climberevan

Now that it's finally running, I put some premix in it and rode it! I played around in the vacant lots nearby, which fortuitously have lots of little to medium sized rocks littering them. I managed to make it up and over one from a direction I've not tried before, after about 5 tries.... No broken parts or body, though, so it's a success! Man, this thing is fun.

Further update: I received the good used coil from lineaway (thanks!), and installed it. The bike started first kick as expected, and ran fine....for about 30 minutes. ARRGGH! Suspecting fuel, I pulled the carb & cleaned the passages, but it would only crank intermittently and would only run at high revs... The real clue came when I reached down and touched the tank and was rewarded with a nasty shock. Aha! I turns out that the spark plug boot was so tightly smashed against the back side of the cooling fan that it had worn through and was allowing the spark to jump to ground there, instead of in the plug! When the boot is off of the plug you can't see the tiny hole because it's no longer stretched. I had noticed it before, but thought it didn't matter--my bad! The radiator looks good and appears to be mounted correctly, but there is just not enough space behind the fan for the boot to go on the plug without pressing hard on the fan. I put in a jumper (spare car coil extension wire) which has a much lower-profile plug connector, and everything seems to be working beautifully. It's a kluge, but I can't see how else to get it to work. I can't say at this point whether the original coil was killed by the shorting wire, or whether it's actually just fine and I could have just replaced the plug. I'm not going to take it apart again to find out right now--too much riding to do!

Well, I drained and changed the fuel to fresh-from-the-pump 91 octane (I'm at 5000'), mixed 80:1 with Maxima. Nope. I changed the plug, again. Nope. I gapped the plug to .3mm, which I'd read somewhere would help. Nope. I removed and tested the coil, which seemed to be within the range: .7 ohms primary, 8.8 kohms secondary. I haven't found a GG spec, but this seems normal. Then I thought to myself: the KTM 200 runs like a banshee and is roughly the same size motor, so perhaps it can be an organ donor. It's down for a clutch replacement anyway, so it's half-disassembled and sitting right beside the GG. I swapped in the coil from the KTM and... IT'S ALIVE! First kick, super smooth. I tried it several times to be sure. So, I guess coils DO fail. Anyone have a coil I can buy? THANKS everyone. What a relief!

Thanks to a very helpful and generous fellow trials-er, I had the opportunity to swap in a known-good CDI. Still no starting. It will fire once or twice, then dies, just like before. I'm really starting to suspect the fuel delivery, but I took the carb off and attached it to a vacuum to confirm that it's delivering fuel, and it is. This thing is driving me CRAZY. What's next? Stator? How do I test it?

Compression test results: 130 psi throttle closed, 140 throttle open. Stabilizes after 4-5 kicks. So...I guess we can rule that out.

I put in my local favorite area...

Thanks guys! The kickstarter definitely does rotate the engine in the correct direction (confirmed by rotating it in gear with the rear wheel). Plug out, it keeps turning for bit after the lever is released. It does feel like it has a missing tooth or something and seems to skip a bit about every 20th kick, but I just figured it was catching strangely. I thought about the back-pressure thing as well, especially after it started with no exhaust. I am able to blow freely through all 3 sections of the exhaust, though, so that can't be it. While it was running it was quite powerful--I was actually pretty surprised by how strongly it pulled in 4th and 5th up to speeds that were beyond what I wanted. I'm going to do a compression test today to rule that out.

Yes, the blue marks didn't inspire confidence. I did some more dis-assembly today and found no faults with the piston, stator wiring, exhaust (not blocked), etc. While the header was off I kicked it and it started and ran like a banshee, but I killed it immediately since I wasn't sure if it was OK to run without the header. I then re-assembled everything and...nothing. I took off the exhaust and tried again, but no dice. Now it seems to fire a little, and backfires sometimes when I've been kicking for a while, but the most it's done is a couple of fires. I moved the stator in its slots to retard it as much as possible (which corresponds to about 13-15 deg BTDC), but it changes nothing. The guy at Lewisport didn't have any suggestions, but he seemed confident that it wasn't the CDI ("They almost never fail."). He said that 20 degrees of advance was WAY too much, though. He thought it should be about 4. I, however, am really starting to think this is it. It's not cheap, nor returnable, so I don't want to buy one if there's any other explanation. Arrgh.

I removed the reeds and they look fine, with a decent seal. Even if they aren't perfect, the bike should still run. Whilst spinning the crank with my drill I noticed the timing does change. At lower RPMs it was less advanced, perhaps 10deg, then moved up to the 20deg mark and stayed there. The blue marks were on it when I acquired it, and as you can see it's on them. Should I just move the stator to retard it and see what happens? Let's put the woodruff key question to bed:

Awesome, thanks for continuing to help, everyone! I employed the dial indicator method of TDC location and determined that my original mark was a bit off. Using my more accurately determined mark I find the plug firing point to be more like 20 degrees BTDC. Turning the engine with a drill results in a good looking, blue spark every time. I also cleaned the grounds and made sure everything was tight. I can't understand why I'd need to replace the woodruff key if it's perfectly fine, but I can do it just in case. The engine is not at all hard to turn with the plug out. I can easily turn it with my hand on the flywheel. It's just that when the plug is in the compression is a bit more substantial than I'm used to on my KTM 200, I guess. So, at this point it appears that the ignition is in fact doing what it's supposed to be doing, so I suspect the fuel delivery system. The reeds look fine, and I took the carb off and cleaned it again, verifying that there was fuel in the float bowl. What else could be preventing this thing from starting? I'm at a loss.

Thanks for the replies guys. In my first post I wrote: "I removed the flywheel and checked to see if it had spun on the shaft--nope, and the Woodruff key is in place. Stator is on its marks and looks fine." So, any suggestions other than the already-ruled-out Woodruff key? Does anyone know what the proper timing should be? It seems lots of 2T are around 17 deg BTDC, but I can't find the spec for this one.

Thanks for the quick reply. I hadn't thought to use a drill to turn it over... The flywheel feels very solid, btw. I finally got the timing light to work, but I had to put in a jumper of bare wire from the plug wire to the plug and clamp the pickup around it. I've tried to attach a photo. The longer mark on the case is TDC , as best as I could find it using a screwdriver through the plug hole. The smaller mark, well before TDC, is where the crank mark hits when sparking. Using a protractor I find it to be ~23 deg BTDC. I can't seem to find the spec for it, but that seems like a lot... Should I adjust the stator in its slots to bring it closer to TDC? Thanks!

Hi all, I'm new to the site, and to trials. I just bought an '02 TXT 280 (regular, not Pro). It appeared to be in good used condition, and well maintained (clean oil, clean filter, lubed pivots, etc). It started first kick whilst I was checking it out. Fast forward 2 weeks, and a lot of driveway and several more adventurous rides. I rode it on some trails/rocks for about 2 hours, and it seemed to be running OK, but was kind of hard to get started after stops on that ride--it really required a firm kick. The next day I pulled it out to ride again and it didn't want to start. I leaned the bars against the shed and started kicking away, and eventually it sputtered a bit and seemed to be running poorly, but running. The problem is that it was running IN REVERSE. I put it in gear and it took off backwards! I then shut it off, and kicked it like a mainac some more and it eventually started up and ran again, also IN REVERSE. So I shut it off and tried to bump start it to force it to run forward, but it wouldn't start. I have been unable to start it since. Things I've checked: Entire fuel system removed, totally disassembled and cleaned (blown out too), then re-assembled with fresh 80:1 fuel I removed the flywheel and checked to see if it had spun on the shaft--nope, and Woodruff key is in place. Stator is on its marks and looks fine. I checked the rest of the ignition stuff as best I could, and replaced the spark plug. The coil resistance checks out, and the stator puts out about 35V AC while kicking it over. It makes a spark, but it looks really weak. I compared it side-to-side (with the GG's plug) to my KTM 200, and it looks a lot stronger on the Katoom. It appears this year has a type of CDI that takes only 2 wires from the stator and does not have a pulser coil at all--I guess it senses voltage spikes and sparks it based on that. At this point I think it must be ignition as fuel is definitely being delivered. Ignition parts don't seem to be inexpensive for these, so just throwing parts at it is not an option. Ideas? Huge thanks in advance--I really want to play with my new toy. Evan in NV