stork955

Gday, did you fit the seals the correct way around? The "sharp" lips point to the fluid. Also, if there are any scores, scratches or corrosion in the bore the cylinder needs replacement. Sometimes they can be polished out with fine (800-1000 grit) wet and dry on a stick in a drill if not too deep. Cheers, Stork

Gday, your fan should come on when the cooling system reaches around 90 degrees C. You can do a quick test by shorting the two wires from the thermo switch on the cylinder head together (the one that is in the way of the spark plug). This will make the fan run. If that's OK its probably all good, the fan will usually only run while the bike is sitting idling while waiting to go into a section etc. Your coolant level should be around 25 mm below the filler cap. Cheers, Stork

Gday all, I should have said that Jon, I knew that... of course the leakdown test by itself only tells you if there is a leak. Anyway - I was wondering are the Sherco mufflers repackable? (In that they come apart for cleaning and repacking) For the record I have had a few earlier (1999 - 2001) Sherco front and mid pipes in my cold parts cleaner tank for cleaning with no adverse results afterwards and it works well. For you other guys in Aus I use Hunters' Carbo Clean in a 25 litre plastic bucket. Also really good for cleaning your barrells and other engine and carb parts but nothing plastic. If you can get some it might be worth a try to make sure the inside bits of those pipes are really clean. At least then you have a known good point to work from. Cheers, Stork

Gday Neo, don't worry about the hunting while warming up - keep in mind that the engine is probably just off choke but not at operating temperature yet, so don't go looking for a cure for this as you will only upset some other aspect of its running. As for the pinging thing in 2 strokes it can be related to the squish clearance between the piston and the cylinder head. Obviously this is measured with the head off. There is a heap of info on the internet about this topic, google Squish band and this will be rewarded with a plethora of info. Another thing I thought of yesterday, which may have some bearing on your bikes, was a Gas Gas I did some work on for a guy in my local club. He was having some issues with it, primarily poor idle and slow running stuff and we cleaned the exhaust etc, reset his carb to standard and he freshened up the top end with rings. I noticed the base gasket had been displaced from under the pot (probably from new) and was leaking the smallest amount. This was not visible from the outside of course. A leak down test as Jon suggested will reveal this, but not show where it is occurring... Importantly this can happen mostly when sealers or grease are applied to the gasket - a lot of modern gaskets are impregnated with sealer so it is not required, neither is it required on normal paper gaskets. The gasket surface should be perfectly clean and flat, that is the most important thing. Anyway, that might be worth having a look for on your bikes. Cheers, Stork.

Gday, I prefer to use rubber grease on any brake stuff. I guess there's little chance of contaminating the seals but it "could" happen. Cheers, Stork

Gday, I run a DT Wiseco in my A, with no modification. It goes well. I'm a bit worried about the preload you have measured across the mains - ball brgs. will not tolerate any axial thrust at all, and there should be no preload on them at all either. Ive not yet seen any ball roller main with preload (and I've built the odd few engines over the years...) It might pay to recheck your measurements there as 1.5 mm is a lot, even if there was meant to be preload there. You should see if anything a small amount of freeplay, like a thou or so. HTH, Cheers, Stork

Gday, a 6 is too cold. If Scorpa recommend a N12YC the correct NGK replacement is a BP4ES. Much much hotter. You might get away with a 5 but not a 6. Iridium plugs will only lighten your wallet, especially if they are the wrong heat range. HTH Cheers, Stork

Gday, no help to you but good luck drilling out the ezy-out. You may have to get it spark-eroded out, which may be the best way to do the job anyway. For what its worth, I never use ezy-outs, as they are more trouble than they are worth. If a bolt breaks with a spanner on it, there is no way the ezy-out will move it. Once it's out you will need to see what method they used to seal the bleeder, most bikes use a taper on the end of the bleeder which you'll need to reproduce in the larger size if you go that way. The other method uses a ball bearing against a flat ended nipple into the fluid passageway. Much easier, only if the passage is in the centre of the hole. For future preventative measures give the bleeder a lick of rubber grease before fitting to stop future corrosion. Cheers, Stork

Gday all, I was just perusing the Elextrex website when I came across this gem - http://www.electrexworld.co.uk/beta-enduro-9051-0.html Perhaps an alternative for when your Techno stops... I assume the US Electrex site will have them there as well. Cheers, Stork

Gday, just to add fuel to the fire... The DT's have a different crank assy. so that may have some bearing (no pun intended). It does make some sense to shim the primary drive for alignment but I cant remember my A engine having anything there. Probably not much help... Cheers, Stork

Gday Dave, weird! Does it sound like its coming more from one side side or the other? I know its hard to tell sometimes but this may help isolate the noise. You can use a long screwdriver handle pressed into your ear and using the tip as a probe (like a doctors stethoscope) to help pinpoint it. HTH Cheers, Stork

Gday Neo, in cases like this I think it's really important to diagnose carefully and logically, looking at one area at a time. This is how many of the bikes I work on come to me - it takes a couple of hours to fix the "fixes" to get to the root issue... Like Jon said, what are the exact conditions you notice that lead to the fluctuating mixture issue? eg - hard starting, cutting out occasionally when idling or at very small throttle openings, misfiring at high load and rpm etc. The best way to diagnose mixture issues is to look at the plug as it is the window into the engine, there are many good plug reading charts on the net that you can download to use as a comparison for yours. Sometimes with 2-strokes its hard to determine if a lean or rich mixture is the problem -sometimes they can give a similar symptom. I also reckon it is best to start with good solid basics, like clean carb and filter set to "factory" specs, clean pipe (which you have now done - that makes a huge difference in itself to general performance) and good general engine condition which you also have by the sounds of things. Stick with it! Cheers, Stork

Gday, They are the same I think(?) don't quote me on that! According to the '04 parts cat. 250 and 270 are the same. Cheers, Stork.

Gday Andy, all your clutch adjustments are at the clutch lever. There is one which moves the lever in and out and one for the free travel part of the adjustment. 90:1 is a leaner oil mix (less oil = more fuel) so that could be the issue for you. My bike (270) runs beautifully with a clean pipe and all standard settings - the plug is literally a coffee colour - couldn't get better if I tried! Where was the needle before you reset it? Cheers, Stork

Gday, did you fit the seal in the correct direction? i.e. with the open side towards the coolant? Cheers, Stork

Gday Andy, 1. Change your gear oil to ATF (Automatic Transmission Fluid). Use Dexron 3. That will help the clutch but they still do it a bit. Mine sometimes sticks on the first start of the day but that's it. Perfect afterwards. Check also that you have some small amount of clearance between the piston in the master cylinder to pushrod from the lever. This is vital. Then recheck that the rest of the adjustment is OK for you (move the lever in or out until you are happy). The main thing is that the piston returns fully out from the m/cyl "at rest". 2. Fouled spark plugs are never a stator problem. Stator problems cause NO SPARK. Timing problems cause poor power or pinging and engine destruction. Never plug fouling, apart from with aluminium from the piston... (Check your timing as per your other post anyway). If your plug is fouling ( I assume it comes out black and oily looking) it is one of these things - A. Check you have the correct plug - Champion N7YCC , NGK BP7ES (This is what I use and is the correct replacement for the champion) It may pay to start with a new one anyway - they very rarely fail, (once for me in 30 years of doing this for a living) but it can happen. Check the gap 0.6mm and Lube the threads lightly with an Anti-seize grease. B.Check the oil/fuel mix you use (this can and will affect fuel mixture), it should be 1.5% full synthetic 2-stroke oil (70:1 ) Best off mixing up a fresh batch and replacing what is in it now. C. Check and clean your air filter and re-oil it. Make sure any excess oil is removed from the filter. Start the bike up (is it easy to start?) and see how it goes. If it fouls again, you can clean your plug off with Carb/throttle body cleaner and refit. Check the carb now, remove it and carefully check for cleanliness and "adjustment". Needle in the middle groove, and (I think) 150 main, 30 pilot. Check the float level, the tangs should be parallel to the base of the carb when lightly seated against the needle and seat. Idle air screw 1.5 turns out from lightly seated. Stick it back an and try again, you should be OK. It will also pay to clean the exhaust front to rear, there are many threads on this in the forums, have a look and you will find what you need to know. Good luck, Cheers, Stork

Gday, use a timing light and with the flywheel cover off there is a timing mark inside. Pretty easy really. It shouldn't have moved however unless someone has been playing. Cheers, Stork

Gday, According to my cross-reference GT 80's and YZ 80's from the same years are the same. Get the crank apart, it may not be as bad as you think. Cheers, Stork

G'day, if the plug is black its fouled, give it a clean with some carb or throttle body cleaner and stick it back in (or grab a new one) and go back through your carb again. Check the float level and look for any tiny specks of rubbish that might hold the needle and seat open. Clean airfilter? check it while you're there. Clean and fresh fuel? Old stuff can give you grief and the oil can settle out of it. Try all of that and see how it goes. HTH Cheers, Stork

Gday, It sounds rich. What colour is the spark plug? Cheers, Stork

Gday, its best to use a timing light to see what is going on, my Techno has timing marks on the flywheel and I would assume the Rev 3 has also. There are photos on the net somewhere that you can look at to see the basic alignment of the stator to the engine case. Cheers, Stork

Gday Neo, 215 seems a bit high - its probably due for a decoke. Save that till after you sort out whatever is going on now. Little bits of rubber in the carb bowl is generally rotten fuel hose. Definately an issue -it'll cause the float to stay open and flood the bike. Go down to your local chainsaw shop and get some 5mm chainsaw fuel hose for it. Take your big wallet though - its really expensive but worth it as it will not fail in 2 minutes like the stuff you get from repco. Cheers, Stork

Gday, keep in mind that the mixture screw only affects idle mixture... Check ignition timing, needle and main jet sizes/positions. Is the front pipe clean? HTH Cheers, Stork

Gday, you need a big press and a lathe with a dial gauge at least to align it when going back together. Better still a crank alignment jig. Easiest way is to get your local bike shop (any brand) to do the job for you. Or send it to me in Australia, I do them for free for trials riders. Cheers, Stork

Gday Neo, In no particular order - have you checked the floats are not punctured? Drop 'em into warm water and see if bubbles come out of it, - if OK put them in fuel and if they float just below the surface of the liquid they are knackered. Worth a try before fitting a totally new carb... Also, do a compression test -its better to diagnose properly than to feel around in the dark and hope you get it by accident... Clean exhaust system? Filter clean and oiled correctly? I like to blast carb cleaner (from a can) through the carb passage ways to really make sure they are clean. Jets too... Wear on the needle and/or in the needle jet? With a drill bit that just fits into the needle jet look for ovality. Any wear here means a new one and a needle (this will cause rich running off idle), blocked air vent hoses? Umm, cant think of anything else at the moment. - Oh - float level and needle and seat? No wear on the needle valve, adjust with the carb tilted sideways to around 45 degrees. This makes sure that the float level is correct, and no float weight error is included in the adjustment. Cheers, Stork