2002 XR400R: Difficult to start when hot.

run29point2

Member
Jul 2, 2002
9
0
Hi Gang:

I bought a new 2002 Honda XR400R about a month and a half ago. I have had some problems starting it cold with the choke open. But when I close the choke, it will start. Sometimes, it dies after idling a few seconds after starting it when it is cold.

The other day, I got 'her' started and rode for about an hour. Going downhill in 3rd gear, the engine stalled out. And then for the next hour or so, I could not start it no matter what I tried. After about an hour, when it cooled down it finally started.

I replaced the spark plug and upon inspection, the electrode was all black and sooty-and that's only after the first 30 miles in the life of the bike.

So, my main complaints are:
1). Difficult starting cold.
2). Flooded on occasion upon cold starting.
3). Will not start when stalling out when engine is warm from use.
4). Very black spark plug electrode early in engine break-in period.

I'm thinking that the pilot jet may be set for too rich an air/fuel mixture (difficult if not impossible to start when hot) as well as maybe the same being the case for the main jet(black spark plug). I'm thinking that likely, the pilot jetting is set too rich at the factory or upon dealer assembly since most of the problems seem to be with starting (mostly when engine is hot).

I would appreciate anyone's help, expertise, and feedback as to what the problem might be and how I or the dealer can correct it. The last thing I want to have happen is to be 20 miles from my car and my bike stalls out and won't start :-(

Thanks Gang!
 

JRork

Member
Sep 3, 2000
12
0
I also have a 2002 XR400 and struggled constantly with starting it and keeping it running.
This is what I did thanks to some great people on this board and others.

Switch the main jet to a 160
Switch the pilot to a 60
Remove the airbox lid
Remove the header pipe and look at where the flange that they weld onto the header pipe so that it may be bolted to the head. The weld bead is so large that is restricts the diameter to half size. Grind that down a bit. Not too much. I think I used a socket but I can't remember exactly which size but if you email me I can give you some other ideas.
I also modified the cap on the muffler also.

With this setup now, I follow the following routine.
When it hasn't started for a while
I put the chock on full, Turn up the idle screw know about a full turn, pull in the compression release, Thumb on the kill button, throttle wide open, kick the engine over 3 to 4 times.
Then let go of everything but leave the choke on.
Find TDC, bump it just past with the compression release and boot it. Starts usually first boot everytime, even when it has sat for months (it's so dusty that we haven't been riding).

Experimant with the choke as it's warming up. Once warm, turn down the idle and enjoy a ton more power and much easier starting.

When warm, and you kill it, just boot it, works slick as a whistle.

Let me know if what I said didn't make sense...FYI, 160-60 works great for sea level to about 2500 feet
 

justdeserts

Member
Aug 31, 2002
1
0
Starting from cold: lean the bike over to the right to flood the carbie. Full choke. Throttle closed. TDC and kick through.
From hot: Throttle closed, TDC and just kick through. If it doesn't fire after a couple of goes or if you've dropped the bike and it's flooded, then close the fuel tap, kick it over about a dozen times with throttle open (you can use the decompression lever) then close throttle and kick through from TDC - don't forget to reopen the fuel tap again after it starts! If all else fails take a break while it cools!
 

hug747

Member
May 14, 2001
46
0
Owned a 96 XR400R for five years and the only time I had trouble starting the bike was after I turned the idle screw to lower the idle. Occasionally, after a fall it gave me some problems, but just follow the procedure in your owners manual. If it wasn't for the weight I would have bought another one. You've bought a good dependable bike in my opinion, keep the oil changed and ride.
 
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