What did you do to your WR today?

[rholbrook]

Well I tried to put my 07 on the charger so it'd start but it still just clicked... I think it's a relay or something cause I can hear the starter trying to turn. Any helps appricated and I've got another thread going, trying to sell it and the starting issue is a black eye

Bad battery. Mine was the same way. Replaced it last fall and it fire right up now.

[ofgofg]

I changed oil in both bikes today. Oil from dirt bike was black and thin! From supermoto it was dark honey colored still. Dirt bike sounds slightly better although still some mechanical clatter. Supermoto sounds like a new bike!

[redswr]

waited and waited for the guy to call me back on it so i finally went rock bottom $3,000 on it and he said "yeah i was just about to call you" ? there went plastics for my 99

[Shred Jesse]

waited and waited for the guy to call me back on it so i finally went rock bottom $3,000 on it and he said "yeah i was just about to call you" ? there went plastics for my 99

Where are full plastic kits for the WR400's????

[redswr]

Where are full plastic kits for the WR400's????

i'm getting everything on the UFO website and i talked to a guy there and he said type "kit" into the order where it says code and it give 15% off... it's $281 but thats with mud guard, chain guard and chain glide too, if you go yz fender it's $40 cheaper http://www.ufoplasticusa.com/part.php?brand=6&model=67&year=1999 . everything but the headlight but i'm getting this one http://www.bikebandit.com/trail-tech-x2-motorcycle-headlight

[Shred Jesse]

Noice! Everything I would need for my bike would run me $156.37. Might not be a bad idea to have lieing aorund incase I ever want to sell the thing. Pristine plastics go a LONG way!

[Shred Jesse]

Oh yeah, and I rode my bike around Sunday. Everything was pretty good, except I am not so stoked on the FMF powercore 4 compared to the white brothers exhaust I had. While I am definitely not going back, I lost all my overrev, I feel a lot more sluggish on the top end, and I'm having to use hot start way more often in situations where I normally wouldn't.

All signs of the bike running lean I suppose though huh...

Oh, and the exhaust being relatively quieter sucks because I can't quite hear the engine as well anymore.

[davidl9999]

Oh yeah, and I rode my bike around Sunday. Everything was pretty good, except I am not so stoked on the FMF powercore 4 compared to the white brothers exhaust I had. While I am definitely not going back, I lost all my overrev, I feel a lot more sluggish on the top end, and I'm having to use hot start way more often in situations where I normally wouldn't.

All signs of the bike running lean I suppose though huh...

Oh, and the exhaust being relatively quieter sucks because I can't quite hear the engine as well anymore.

No. That sounds rich. Retuning is a must-do any time the intake or exhaust flow changes. Drop a size on the MJ and see how that works for you. Fwiw, a quiet bike is a plus when it comes to keeping trails open.

[Markjb85]

Oh yeah, and I rode my bike around Sunday. Everything was pretty good, except I am not so stoked on the FMF powercore 4 compared to the white brothers exhaust I had. While I am definitely not going back, I lost all my overrev, I feel a lot more sluggish on the top end, and I'm having to use hot start way more often in situations where I normally wouldn't.

All signs of the bike running lean I suppose though huh...

Oh, and the exhaust being relatively quieter sucks because I can't quite hear the engine as well anymore.

definately think you should change your jetting, i went from an old white brothers to a powercore 4 on my Wr400 and it was heaps better.

[Shred Jesse]

No. That sounds rich. Retuning is a must-do any time the intake or exhaust flow changes. Drop a size on the MJ and see how that works for you. Fwiw, a quiet bike is a plus when it comes to keeping trails open.

Correct me if I am wrong but...

Needing hot start more often (after riding) is a sign the bike is running warmer... which is generally a side affect of running too lean.

Loss of power on the top end in conjunction with that relates to that as well right?

I'm going to buy a JD jetting kit and take my bike to the dyno tuning day coming up here in Portland. $50 a run, and then I'll really know what's going on!

[davidl9999]

Hate to do it, but yeah, that's wrong.

A hot start is the opposite of a choke. When you pull the hot start, you add air and that leans the A/F mixture. If the bike was already too lean, then pulling the hot start would make it even harder to start. A little more: as the bike warms up it needs a lower a/f ratio (e.g. why you don't need the choke to add fuel after a few seconds from a cold start). It's often the case then that a "was running a minute ago" 4T that is restarted is hot enough that the a/f ratio when starting on the pilot circuit is too rich for that engine temperature. Adding a shot of air with the hot start leans the mix and makes it possible to start these beasts.

While being too lean will also make the bike run under-powered, very often the bike runs better and better with great overrev the leaner it gets until you go a jet too lean and it "falls off the cliff" in power. One of the reasons the 2T folks get concerned about being too lean even though the bike seems to be running super well - you can already be "too lean" (and have high EGT and poor oiling) before you start to have power problems. Too rich is often a "burbly" WOT and sluggish mid. Having to pull the hot start was the big clue for me here.

+1 on the JD kit. I like the feel of their needle and the instructions are invaluable.

Edited April 19, 2011 by davidl9999
can't believe I didn't finish a sentence. That's what I get for doing this whilst working late... :D

[redswr]

i got the throttle tube and grips i ordered for the 99 in... couldn't get the throttle apart though so i'm gonna have to cut it apart, damn philips ?

[Shred Jesse]

Hate to do it, but yeah, that's wrong.

A hot start is the opposite of a choke. When you pull the hot start, you add air and that leans the A/F mixture. If the bike was already too lean, then pulling the hot start would make it even harder to start. A little more: as the bike warms up it needs a lower a/f ratio (e.g. why you don't need the choke to add fuel after a few seconds from a cold start). It's often the case then that a "was running a minute ago" 4T that is restarted is hot enough that the a/f ratio when starting on the pilot circuit is too rich for that engine temperature. Adding a shot of air with the hot start leans the mix and makes it possible to start these beasts.

This much I knew, and knowing my bike and the situations that required hot start I was thinking too lean, however...

While being too lean will also make the bike run under-powered, very often the bike runs better and better with great overrev the leaner it gets until you go a jet too lean and it "falls off the cliff" in power. One of the reasons the 2T folks get concerned about being too lean even though the bike seems to be running super well - you can already be "too lean" before you start to have power problems. Too rich is often a "burbly" WOT and sluggish mid. Having to pull the hot start

This makes excellent sense! I will definitely give it a go and see where I wind up. after rejetting.

I'm also going to find a rear tire to run on the dyno day coming up here in Portland, after I do the JD jet kit. Then I'll REALLY know what's going on!

[Twenty36_1]

Finished my 07's complete overhaul, new look. It was time for a new bike but with the costs of a new one versus the used market, not to mention this bike was already so customized for me, suspension, ergos, etc. So I decided to throw a bunch of money at this bike and make it new....

List goes;

new valves, springs, seals and exhaust guides

piston JE 13.5-1

camchain

rear camchain guide

Jardine exhaust

balancer shaft and bearings

impeller shaft and seals, bearings

new needle jet emulsion tube in carb

Trail Tech stator and reg

Trail Tech X2 headlight- no pic yet, coming soon

various new chassis bearings

chain and sprockets

brake pads

tires

handguards

plastics

graphics

Had head flow ported, and went with YZ intake and WR exhaust cam this time to retain the estart.

Rebuilt forks and shock, SKF fork seals ? and a general greasing, and polishing of everything.

That's all I can remember right now anyways....

Now I just have to wait for it to warm up out as she's being a bitch to start ?

A couple shots of the motor during rebuild

The head

Did you need to use the YFZ resistor kit? I want to remove the headlight and replace it with a YZ numberplate, but I am curious if the resistor kit was needed or not. Thanks in advance.

[Shred Jesse]

Did you need to use the YFZ resistor kit? I want to remove the headlight and replace it with a YZ numberplate, but I am curious if the resistor kit was needed or not. Thanks in advance.

I'm curious about this somewhat, as I removed my headlight, but do you really need a resistor kit to balance that out? After all, there is a switch to turn the headlight on or of...

[davidl9999]

Yes. I sent a PM to Twenty36_1 about that last night.

On the bikes that don't have the switches (pretty sure that's '01 and up, maybe newer than that), the regulator has to drop more current than it can handle (long term) and overheats; eventually it fails. Plenty of folks just pull the light and install a number plate, but the proper way to do the mod is to install the 35W YZF resistor (about 3 ohms) to protect the regulator.

The $45 kit: http://atv.off-road.com/atv/project/project663.html

An earlier post on this: https://www.thumpertalk.com/forum/showthread.php?t=802757

[byggd]

Oh, and the exhaust being relatively quieter sucks because I can't quite hear the engine as well anymore.

Powercore4 quiet? You must have been running 8 or 10 plates in that e-series for the PC4 to seem quiet. My son had a PC4 on his YZ450F and it was HELL loud compared to my q-series. On road "loud pipes save lives" but off road "quiet pipes save trails"!

[Shred Jesse]

Powercore4 quiet? You must have been running 8 or 10 plates in that e-series for the PC4 to seem quiet. My son had a PC4 on his YZ450F and it was HELL loud compared to my q-series. On road "loud pipes save lives" but off road "quiet pipes save trails"!

I ran only two plates.

The Powercore 4 is loud off of idle, but it doesn't get a ton louder as you go up in rpm.

[byggd]

I ran only two plates.

The Powercore 4 is loud off of idle, but it doesn't get a ton louder as you go up in rpm.

Are you running a spark arrester and or a quiet core insert?

[Shred Jesse]

Are you running a spark arrester and or a quiet core insert?

Spark arrested: yes.

I didn't receive a quiet core with mine... unless it was already installed. if that's the case, yes I am running a quiet core!