steveenduro

Jon - I made a note of the jet sizes when I stripped the carb down and can't find it! I'll open it up again, and check the reeds as I doubt whether they have been touched since new if the rest of the bike is anything to go by. Peter - The crank seals do worry me, but the bike runs clean and maintains gearbox oil, so I'm hoping it's not. My KTM motor is in bits now, and has noticeable play on the crank at the clutch side - so it's a case split job. So I'll stick with the small jobs for the time being on the txt and see if they resolve the problem. I will at some stage have to tear the bike down as the "growl" on shut-off when in gear needs to be addressed. Cheers Steve

I'm using 80:1 synthetic. Plug does look oily though - more than I would expect. Started today after about 6 or 7 kicks, choke on but throttle open! I may take the carb apart again even though it looks clean. Steve

The vinegar worked a treat! I put the solution in, started the bike (eventually), and run it until the fan came on. Drained the solution, and flushed with water. The scale that I could see just inside the top of the rad was virtually clear. So it's all back together, but still a pig to start. It's getting a good healthy kick (my right leg muscles are much bigger since I bought the bike). The carb had a good clean. I've tried all settings of the mixture screw. The flywheel to pick-up gap has been tried at 0.4mm and 0.7mm. (The videos say 0.7mm, but a recent post said 0.4mm)? I've tried conventional plug (BP5ES) and iridium plug. New air filter. Fresh gas. Changed plug cap. The plug gets wet, and there is a spark at the plug, though it still seems a little weak and does not always spark between the electrodes. What seems to work sometimes when hot is - couple of kicks no choke, couple of kicks with choke, the kick wiyhout choke and full throttle. It seems as though I have to flood it intentionally and clear it! I've also noticed that if I tip the bike over on it's side, the carb doesn't pee petrol out. Is this right? Every bike I've owned did, but the delorto may be quirky. I've checked float height and it's as spec (18.5mm to the tangs IIRC). I guess it has to be spark, or fuel. If I could find out which one, it would narrow the search. Is there a definitive way of checking ignition side - coil resistances etc. Steve

Hi Peter. Not going yet, but mostly back together. I couldn't get the barrel of without taking rad out - must be a knack to it! I did have a dykes ring, but replaced them all anyway whilst it was apart. Old base gasket was 0.8mm, so replaced with the same, and also the top o rings and exhaust seals. Found dirty water only in rad - no antifreeze, and lots of scaling. Tomorrow I plan to start it with a 50/50 mix water and white vinegar to clear scale, then refill with coolant. Unless I get a "OMG, don't put vinegar in it!" reply. I'll let you know how it pans out, but for now, as long as it runs it will have to do, as I need to do a mains/crank rebuild on my KTM 200. Took the flywheel of that tonight in about 5 seconds with my new cordless impact wrench, after hours of struggling with makeshift holding tools, locking back wheel etc etc. Should have bought one years ago! Suppose I may need it to do mains on the txt one day too, but don't want to think about it. Mind you that rough whine on shut off is suspicious, but definately sounds more clutch/gearbox than mains. Think I'll have a drop of rough whine myself now. Oh well, we enjoy tinkering really, don't we? Cheers Steve

Thanks Jon. I'll ease a touch off the rings with a file. Any ideas of the max. end gap spec. on these motors? My top ring was ok at 0.3 but mid and bottom were 0.5mm and 0.4mm. I'm changing them anyway, but it would be good to know for future. Steve

Thanks. Yes I have 2 regular rings plus a top L shaped "dyke" ring. I have received one dyke ring and a regular ring. These fit in the bore with a 0.2mm end gap. I guess that the clearance is enough? I'm getting hold of the 3rd ring and will re-assemble. Steve

Hi. Just ordered a set of rings for a 250 txt pro 2002. The ones on the bike have 2 "normal" rings plus a top ring with a lip. I've just looked at the parts list for a 2003 pro, and it just lists a pair of rings. Do I have a non standard piston/rings or is the top lipped ring not part of the piston ring assembly? I hope to receive the parts tomorrow and re-assemble, so any replies appreciated. Thanks Steve

Thanks for your help. Kicking technique is something I need to master, but I can't help thinking there is something else amiss. I too the barrel off tonight to have a look. All seems suprisingly good. The chamber is a bit sooty and wet, and there is more oil in there than I expected. Gear oil level seems a bit lower, could it be making it's way in? The barrel has very light marks but no real scores. I can't feel any play in small or big end bearings. I left the piston in place and removed the rings, and looked at end gap when placed 10mm from top of bore. They were: Top ring = 0.35mm Middle ring = 0.50mm Bottom ring = 0.40mm My take on them is that they need replacing, but are not as bad as to cause sig. loss of compression and starting problems, but would welcome your expert opinions. I don't suppose I should re-use existing base gasket and top o rings? (I think I know the answer to that)! To get the right base gasket is it good enough to mic. the thickness of existing gasket, where not squished, and place the same thickness in? BTW, if anyone is removing their radiator for the first time, remember to take of the top hose (with thermocouple) and the HT coil first. It took me a while to work that one out! Cheers Steve

Thanks Peter. The a worn clutch bush would seem sensible - I'll check it out. Are they prone to wear on these bikes? Carb has been thoroughly cleaned, and jets blown through. Float height is good. I've already cut back the HT lead. The spark from the lead will jump 1/2" to ground, but spark seems feeble at the plug. The cap resistance is ok at 5kohm. I think I'll do the top end anyway, just to have a look. Are the bikes still difficult to kick even when compression is low? I think zero maintenance was done on this bike previously, so I'll work through it bit by bit. I'm just hoping it stops short of splitting the crank! Steve

Hi. I've just bought a 2002 txt pro and I'm having problems starting. It is getting fuel and has a spark (though looks a little weak). It is difficult whether hot or cold, and there does not seem to be a pattern to it. Best so far seems to be a few kicks with choke on, then an open throttle kick with choke off. Normally takes 10-20 kicks either way. I've cleaned carb, changed air filter, checked grounds, stator gap. I'm about to strip top end and check rigs etc, but compression feels fine (too much if anything)! Any other suggestions appreciated. Also just drained coolant and it is a light brown, with a greasy feel. Is this just very old coolant of a sign of oil contamination. Gearbox oil looks fine. When throttling off, say downhill, I get a loud whirring, regardless of what gear I'm in. There is also a lot of clutch noise until the the clutch is pulled in, and the bike is placed in gear. I've ridden a 2003 bike, and it is much much quieter. Could it be gearbox related? The rear wheel spokes are seized on nipples, and most are loose, I guess I'm looking at a wheel rebuild? Many thanks Steve