Frustrated with WR400F

Put in a exhaust from Hot Cams...valve clearances are correct:

.15-.20 intake

.20 exhaust (per Hot Cam instructions)

compression good

spark gap/spark tested and good

Carb taken and cleaned at local shop...only cleaned jet area...neglected to clean top half...I took it back to get it done right. Remote fuel/air mixture put in.

Easier to push down starter lever...yet many, many kicks to start. Doesn't hold idle well, little response and then abrupt when does respond from idle adjustment screw.

Not sure if exhaust cam decreases compression to point of making tough to start. I kept on original cable and mechanism for tension and at stop...thus no unintended additional decompression.


Take off carb, go through well.

Take to shop to trouble shoot

Save the shop $ and put towards an Eddlebrook? carb.

In the process put another exhaust pipe on...other than the White Brother's e exhaust which is making me deaf.

Also put a seat on it that doesn't feel like it is made of hard plastic Leggo's.

Bike is otherwise in very good condition...

Still has me thinking of just selling and buying a good condition, electric start, basic, old school, non radiator, easy valve/plug maintenance, less frequent oil changing, more road worthy...dare I say XR650L :worthy:

Thanks for any insight:worthy:

You said spark tested and good, but change to a new one to be sure.

Should´nt need more than 2 top 3 kicks to get it started.

I have both hot cams in my's always easy to start...+1 on changing the plug...when my wr gets hard to start, that usually fixes it right up.

First, double check the cam timing...just to be sure.

Check all the jets, but esp the pilot jet. Many folks clean 'em...William1, who knows his stuff, suggests just replacing the pilot jet. I haven't had issue, so haven't had to try cleaning vs replaceement.

Have you tried various combinations of choke on when hot/cold, hot start open when cold/hot? That may give you some clue on which way to go with jetting...

What are you running for jets? I didn't have to rejet when I went to hot cams, but others have.

When you put in the remote fuel screw, are you sure you put the o-ring and washer back in?

Also, as yours is a 400 with a first gen FCR, 2 other things to check: All of the vacuum hoses for the hot start for cracks and leaks (in fact, I would just replace them); make sure the slide is in correctly (it can go in both ways...the "flapper door" goes toward the head; and look for cracks in the slide and "flapper door" that could act as vacuum leaks.

You didn't say if the bike started and ran fine before installing the Hot Cams. If so, then suspect the cam timing or valve settings. If not, take Birdy's advice and go through everything. Should start easy - don't even think about the 650L, you'll be sorry.

I bought a 1999 WR400F last month. I love this bike! Not sure of any mods. I twist the throttle once to prime, kick once usually barks, then choke and kick again. Usually starts on second kick when cold. Starts on the first kick when warm. The overflow floods and leaks if I leave the gas on. It wouldn't start when flooded with the baffles. I removed the baffles and it started first or second kick.

Why on earth would you take your precious bike back to a dealer that didn't take perfect care of you the first time??

If you can change a tire without losing a finger, you can clean a carb.

Change the pilot jet!

Why on earth would you take your precious bike back to a dealer that didn't take perfect care of you the first time??

If you can change a tire without losing a finger, you can clean a carb.

Change the pilot jet!

uhhhohhh, I'm in trouble! I almost did lose a finger changing a tire.

Any update on this problem????

Follow up to old thread . . . I replaced petcock, fuel filter, carb hoses, and the shop cleaned carb and replaced a couple jets. No leaks and it purrs with the baffles in, so I can ride quietly in the neighbors woods.

Hotcams have auto decompression, you dont need manual compression release!!!! the cable could be hanging up, the exhaust valve would stay open!( NO, COMPRESSION!!!)

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