Using decomp while kick starting?

[Billy]

just pick up a old 2002 wr250f and am new to dirt bikes.

Was wondering if kick starting from TDC with out using the manual decomp lever will do anything bad to the engine?

[Rich]

Nope...is fine...

[Old frt]

Reminds me of old pommy bikes with advance/ retard.
Won't hurt the the bike but plays havoc with knees and ankles.

[Billy]

cheers Rich.

I didnt think it would but have never had to deal with it before now.

Reminds me of old pommy bikes with advance/ retard.
Won't hurt the the bike but plays havoc with knees and ankles.

I find it easier to not use it, starts up first time (unless fuel is left on over night)

[Rich]

I used to use the manual de comp on my XR600 just to get a little fuel in the cylinder, then TDC and a big kick...

I actually removed the auto decomp, its for girls, and is just weight that's not needed...

[Rick76]

A Google search says to use the below method. Worked faultlesly for me on WR400F. When I sold it the guy who bought it said he owned one several years before, but he had trouble starting to take it for a test ride as he was just kicking the sh*t out of it with no real method. I showed him this method and it started first pop. The 250 may be easier to start anyway.


[These are the supplemental instructions for starting Yamaha YZ/WR 250, 400 and 426 4-stroke singles.]
The decompression lever should be used only while rotating the engine just past top-dead-center on the compression stroke. Do not use the compression release during actual kick starting.

Starting a cold engine

1. Shift the transmission into neutral.
2. Turn the fuel petcock to "ON" (or "RES") and fully open (i.e. pull out) the black starter knob (choke).
3. Leave the throttle closed for starting. In temperatures below 41 degrees F. (5 degrees C.) only, first twist the throttle three or four times to pump some fuel into the intake tract; then close the throttle for starting.
4. Slowly depress the kick start lever until you begin to feel resistance. Continue depressing the kick lever slowly until there is maximum resistance, which indicates the piston is at TDC (top-dead-center) on the compression stroke.
5. Pull the decompression lever to the handlebar and hold it.
6. Slowly depress the kickstart lever about 1.5 to 2" (40-50mm) more. This puts the piston just slightly past top-dead-center.
7. Release the decompression lever, then allow the kick starter to return to the uppermost position.
8. With the throttle completely closed and the decompression lever released, start the engine by kicking the kick starter forcefully with a firm stroke.
   Do not open the throttle while kicking the kick starter.
   Otherwise, the kick starter my kick back.
9. Run the engine at idle or slightly higher until it warms up; this usually takes about one or two minutes. Do not warm up the engine for extended periods.
10. The engine is warmed up when it responds normally to throttle with the starter knob (choke) turned off (pushed in).

---

Starting a hot engine

1. Shift the transmission into neutral if you can. Starting in gear with the clutch adds drag and makes it harder to kick the engine over.
2. Turn the fuel petcock to "ON" (or "RES") and fully open (i.e. pull out) the red "hot start" knob. Do not use the starter knob (choke)!.
3. Leave the throttle closed for starting.
4. Slowly depress the kick start lever until you begin to feel resistance. Continue depressing the kick lever slowly until there is maximum resistance, which indicates the piston is at TDC (top-dead-center) on the compression stroke.
5. Pull the decompression lever to the handlebar and hold it.
6. Slowly depress the kickstart lever about 1.5 to 2" (40-50mm) more. This puts the piston just slightly past top-dead-center.
7. Release the decompression lever, then allow the kick starter to return to the uppermost position.
8. With the throttle completely closed and the decompression lever released, start the engine by kicking the kick starter forcefully with a firm stroke. If it doesn't start, repeat this step until it does. It will start, don't dispair (unless you're out of fuel)...
   Do not open the throttle while kicking the kick starter.
   Otherwise, the kick starter my kick back.

[Billy]

yeah I searched a few forums but couldn't find out if it was bad when not using it.

I follow the steps above except for the decompression lever steps. As long as it doesn't cause any long term damage to the engine I won't worry about it.

[agrid]

My Ducati single doesn't have a decomp lever, I have to put my full weight on it for about 20 seconds before it will ease past top dead centre, I bring the kick start back up and kick the bejeezus out of it. Any hesitation results in great pain. It can smell fear and trepidation.

[tinytoolmans274]

i actually used to like the manual decomp on my 02 yz250f . if you come into a corner or something and stall the bike (lock up the back wheel) and you get to the decomp lever quick enough while your still sliding it will fire up again . done it to many times to remember

[Veefore]

My Ducati single doesn't have a decomp lever, I have to put my full weight on it for about 20 seconds before it will ease past top dead centre, I bring the kick start back up and kick the bejeezus out of it. Any hesitation results in great pain. It can smell fear and trepidation.

Wack it in gear and wheel it backwards until you feel the compression build up and the bike resists being pushed backwards. This puts you on the right side of the compression stroke (just past TDC) then stick it in neutral and kick away.