reviving an 88 KDX 200 a few quick queries

[ctbur2]

hey guys excellent to see a great resource for kdx's. i have gleaned a great deal of know how searching around these forums. I have an 88 kdx 200 that i am in the process of rebuilding as a weekend bush bike and have been screwing around wiring up lights and fixing up little bits and pieces that have annoyed me for years in the past couple of days. just a few quick questions that i cannot find solutions to myself.

1. The kickstarter has a unique problem in that it dosent seem to "catch" when kick starting it from cold. If i push it down very slowly it will turn the engine but if i kick it fast it just goes down with no resistance. I am Guessing that this is some sort of problem with the gear mechanism on the kickstarter if anyone has any knowledge of this problem help would be greatly appreciated

2. i am running the lights directly from the magneto, i have already wired up al the lights, switches etc. but have not connected to the engine. There are 2 spare wires coming from the magneto GREEN and YELLOW as i cant test these without reassembling the bike and starting it does anyone know which is the wire intended for lighting system.

3. The bike was stripped of all electronics (bar CDI etc). so i am starting from scratch, do i need a VR for the lights?? i am un fased if they vary in brightness but dont want to constantly blow globes.

4. my carb leaks excessive fuel when fuel is on, off and when bike is running. any ideas what may cause this??

 

[glad2ride]

1. kickstart return spring worn or soft? worn idle or spur gear(s)?

2. sorry

3. Is this an AUS version with the battery on the right side? USA models are different, so you may want to mention which version you have, as this is a USA site with mostly USA model experience people.

4. float level off? float valve worn (rubber tip damaged over time, not sealing properly)?

 

[tgregg]

4. Or dirt in the float needle and seat.Try cleaning before buying new.

 

[ctbur2]

yeah my bike is an AUS model, not sure whether it ever had a battery to be honest. all electrics were stripped when i got it. i will check out float level etc on the weekend, im guessing any kickstarter work will mean cracking the case which i really dont want to do.
thanks for the replys guys, keep em coming
cheers
chris

 

[sr5bidder]

ctbur2

you will only have to pull the clutch inner and outer cover for kickstart issues not split the cases

 

[ctbur2]

If your KDX kickstarter is difficult to use, slipping past the ratchet mechanism and slamming into the footpeg instead of spinning the motor over, it's because your oil is too thick. KDX kickstarters are sensitive to gearbox oil weight for some reason, and you will notice that the problem is worst when the oil is cold and thickest. I have found that 20W-50 causes this problem on my bike.
You can either put up with it, gingerly finding engagement before swinging, or switch to a lighter viscosity oil. Automatic Tranmission Fluid of the Ford (or "F") type is also ideal for two-stroke gearboxes as it's designed to cope with severe forces generated by gear sets and wet clutches. It works well for me. See this thread.
Whatever you do, don't choose an automotive oil that contains friction modifiers. These will cause the clutch to slip and burn out. Many premium car oils contain friction modifiers these days. Be careful.

what do you guys think of this??? im going to try and see what happens. seems to fit my problems as i can start it when hot but not cold,

cheers
chris

 

[glad2ride]

Somehow, I doubt it.

sr5bidder, no two piece covers on 1988 and older. :-)

 

[ctbur2]

pulled apart the carb today, and all jets seem clear, i am unsure of how to check float but i should also mention that the bike, once its running does run very well. i noticed the main gasket is fairly old and crusty i think that this might be causing the leak. ill take the clutch cover off soon and check out the kickstarting mech, is there any particular damage i should be looking for? i was not too convinced about the above solution but the easiest option always seems the best at the time.
chris

 

[ctbur2]

in the process of taking the clutch cover off, but have one rounded out screw on the kips cover:( has set me back a little, but will try drilling it out and unscrewing tomorrow

 

[glad2ride]

Do you have a hand impact driver with screwdriver bit??

 

[ctbur2]

no i didnt unfortunately but i got away with drilling it out ;) i have now removed the clutch cover and spring seems to be ok on the kickstart mech, i noticed the kickstart shaft wobbles around alot but i think this might be normal. anyway ill pull off the clutch tomorrow and see what i can find back there

 

[glad2ride]

The spring provides pressure on two gears, as best I remember. If it is soft, it wouldn't provide adequate pressure. The two gears' teeth may also be worn. I don't think taking the clutch off will help.

 

[ctbur2]

pulled the clutch off today and found that the ratchet and gear teeth on kickstarter mech were a little worn but not too bad i reassembled and noticed the problem, that for some reason the drive gear sits loose when installed rather than pushing against the spring loaded ratchet, creating distance between the teeth which is what is causing the problem. now all i need to do is find a solution

 

[reepicheep]

If the 88 is like the 95 and up...

There shouldn't be much play with the clutch inner cover on. If it has play, it sounds like that cover is not supporting the shaft. I don't remember what kind of bearing is in there... but it sounds like it is shot.

For the engagement mechanism, there can be a few issues. That spring that pushes the gear faces together can have lost it's spring.

The gear ratchet faces can have raised metal ramps. The gears are like metal ramps with steps, so they slide when rotating one way but engage when rotating the other. When they ride up the ramp they can raise a metal lip at the top, which keeps the steps from fully engaging when you try and spin it the other direction. So if you pop them apart, put the engagement faces of each side on sand paper on a flat surface, you can polish them back flush again. You will see when it is all flat again, as the sandpaper polishes the surface. This alone makes a huge difference.

Finally, there is an index mark in the shaft and the lever arm that engages in the case... if you don't line them up, it appears to work OK, but the kickstart lever return spring doesn't have the right leverage, and the whole arm can be floppy.