For the purpose of continuity to this thread below is a PM I received from Tman and instead of keeping it quite I would prefer to reply here so as to create a source of reference. Or some shit like that

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Ticketyman wrote: Adrian, I took this puppy out for a run today after checking oil pump etc.
I found that the clutch was mildly slipping in 3rd, 4th, and 5th but the more I road it the better it got. I don't think it's been ridden bugger all in the last 6 months. It had a full rebuild 3000klms ago and was serviced 8 months ago and has only put about 50klms on the clock since.
This is going to be a road going bike but was wondering what simple things I can do to this baby to get it running stronger whilst maintaining reliability? I removed the restrictive baffle from the exhaust today but I realise this want make much difference. What's your advice.
Tman.
In regards to the clutch. The clutch springs are not very strong from the factory and it is possible that gearbox oil that is being run at present is too good. Gearbox oil for 2 strokes these days are based upon the needs of current model bikes such as MX bikes and race reps like the Aprilia's. These bikes of course are designed for a much higher HP output and as such have much heavier clutch springs that can disperse the slippery stuff from the clutch plates. The KH however is just a humble 2 stroke pack horse and is quite happy with the most humble of oils. Remember its age and the parameters of oil quality at its age of design - the worst oil you can find at Kmart is probably better than the best of its day. Sooooo you will need to try a different oil in the box. Simple and cheap really since they only hold 600ml. Try some Advance SX because it is quite possible that when it was serviced they added a specific lightweight gearbox oil - SX does the same stuff or any other mineral based motorcycle oil. Thats the simple option.

I run ATF in the engines I have but that's because I have made modifications to the clutch. ATF has a much lower viscosity and can give a smidgeon more power because of less drag within the gearbox. To modify the clutch there are a few options. Add another friction plate to the clutch pack - this pretensions the springs and takes up the wear they will have most definitely have suffered plus the wear to the clutch plates themselves. Or you can purchase a heavy-duty Barnett clutch pack for around $160 and fit that. Modifiying the clutch can be done with the engine in and can be done in under an hour. Try changing the oil first though.
More power but still reliable? This is a contradiction of terms but there are still a few things you can look at doing to ensure its running at its optimum before looking for more power.
1. De-coke the exhaust. Simple and effective for any 2 stroke. Now there is a few different ways you can achieve this - Google and you'll see! The method I prefer is to use an electric heat gun - I have a Ryobi from Bunnings about $60 and is stated to reach 600c. Remove the exhaust pipe and IN AN OPEN SPACE direct the heat gun towards the inner edge of the header pipe. The carbon and oil buildup there will start to glow after a short period of time, once it does then direct the airflow of the heat gun directly down the exhaust pipe. What you have done is start the carbon and crap burning by keeping the hot airflow going down the exhaust pipe you are sustaining the burn and accelerating the burn. If done correctly - and this takes about 20 mins on one of these original pipes

- you will see a glowing red ring travel down the pipe. Be warned though that this does create an absolute shitload of smoke and fumes that neither you nor your neighbours should ingest. So make sure they are out and the washing isn't on the line ( I learnt that the hard way from the missus ) and try to do this on a windy day to help dissipate the cloud of smoke. An alternative to this is to use an Oxy Accet torch if you have one and set the carbon / oil alight and then turn off the Accet pumping straight oxygen down the pipe. Its much quicker but nevertheless creates 5 times more smoke 5 times more quickly. That Baffle you took out is nothing more than a rolled up piece of glass fibre that is no doubt dripping in unburnt oil. Wave the heat gun at this and watch the oil catch alight - once again smoke warning. The Glass will not burn but the oil will - place it on a fireproof surface of course. once your done it will be brand new. Put it back in. This is in the essence of keeping the bike original - very few are these days and it may add to resale value in the future as funny as it may seem. The baffle adds nor detracts anything to the engines performance.
2. Make sure its carburating properly. 3 things to check here. Air filter is clean, airbox is sealed and the plenum chamber in which the carburettor sits is sealed so as the only air the carburettor is receiving comes through the air filter. On some of these engines there is a rubber grommet that sits at the very front RH side of the carburettor housing that allows screwdriver access to remove the carburettor clamp. Often this is missing and this can cause the carburation to run lean as it is jetted for use with restriction through the air filter. Check that this is in place. I will grab an engine and photograph it later for you if you cant see what I mean. Your carburettor is a VM19 and has only one adjustment ( aside from it being clean ) and that is the idle mix screw - 1.5 turns out. This can vary with age and the unknown history of previous users. Adjust it from all the way in until it both idles smoothly and revs cleanly from closed to open throttle. You may find a variation from the 1.5 turns out of 1/2 a turn in or out. This adjustment is for off the line, first1/4 turn of the throttle. Useful info here
http://www.iwt.com.au/mikunicarb.htm3. Gearing. If the bike is only going to be used for Urban use then drop a cog on the front to give it a little more pep off the line. standard is 14. go to a 13. While your there check that the chain is in good nick and the rear sprocket also. The driveline of any bike saps HP so ensure that its the best it can be. Standard gearing is 14 front 36 rear 428chain ( dont bother with o'ring). Replace the lot and you'll get change from $100. check also that the rear wheel is running true and not placing a sideways strain on the chain by measuring the distance between the swingarm pivot and the rear axle both sides should be equal. You only have 9HP at the rear wheel from the factory so you cant really afford to lose any.
4. Wheel bearings. Check them to see they are serviceable and add some fresh grease. A set of wheel bearings from a Kawasaki dealer is around $80 - cheaper if you take the lot down to your local bearing wholesaler and get them to size them up. Once again only 9HP don't forsake any.
5. Check that the rear brake is adjusted correctly and is not dragging. Lubricate all moving parts - including the sprimgs - to ensure that the shoes are releasing clearly and cleanly from the hub. Shoe and hub shouldn't be considered moving parts

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These bikes when in fine fettle should be able to be wheeled around by hand like a mid 80's BMX bike - a little heavy but still within the ease of a 12YO boy. If you know what I mean. Nothing should be causing friction or drag against movement.
6. Spark plug. Give it a new one and by a spare one while your at it to bung under the seat.
Thats the Simple diy stuff in it's original form.
More oomph again? Then its engine out and on the bench for some mods. Can be completed "simply" but your definition of simple may vary from mine
My typin finger hurts now
