Old BARFer, New Dirt Rider, Qs About 2007 CRF 450X

PASTAPWR

PASTAPWR

Well-known member
Well, it has been a long time since I have been on BARF. Still riding and recently decided to get into the dirty action. Started off by picking up a 2003 CRF 150F for my son and a 2007 CRF 405X for me.

Bought his 150 in Nevada, re-jetted it for CA and it is running pretty darn good now. Prior to jetting he could barely start it. Now it fires on his second kick.

Now to my 450X. Previous owner had it jetted by Peninsula Honda. Bike was very hard to start. Took about 24 twists of the throttle to prime the carb for a kick start. What about e-start you say? Well the Shorai battery is likely a gonner so I am kicking for now.

So over the last few days I have begun work on the carb. Took it out, did a quick clean and put a fresh main jet 162, as that is what Honda Peninusula had put in and the airbox and exhaust have not been modded. I also put in a JD red needle at the 4th clip position and the 2008 updated accelerator pump diaphragm and rod. Bike fires pretty easily now.

Got a bit freaked out by excessively hot exhaust. Glowing head pipe that started toasting the stock skid plate. Now I know that this bike needs some airflow, but I don't feel like it was idling all that long. Not any longer than it would while trying to adjust the fueling.

Looking for any information. Already been reading Thumper Talk and CRFs Only for information. But thought some locals might be able to help as jetting is related to elevation.

Thanks in advance. Looking forward to doing some Dirty BARFing with my kid as soon as I am sure I have this machine running right.
 
byke

byke

Well-known member
Was thinking that too, except that he was able to fix it with jetting..?

Dave, common problem is the intake valves get tight and make the bike hard to start. You'd be the first guy in history that had success twisting the throttle 24 times on an fcr to start a crf450x. Normally, you need to keep your hand off the throttle. We often tell people to literally move their hand off the throttle tube and rest it on the master or something.

Important question here: when you say that it starts pretty easy now, is that a cold bike? If not, don't count your chickens just yet.

Don't worry about the glowing header, just don't let it sit and idle so long that-that happens. Let it idle for 30-60 seconds and then start putting around until it's warm.

Best to sort out the jetting by symptoms, especially when you get into aftermarket jet kits and different taper needles.
 
PASTAPWR

PASTAPWR

Well-known member
byke said:
Was thinking that too, except that he was able to fix it with jetting..?

Dave, common problem is the intake valves get tight and make the bike hard to start. You'd be the first guy in history that had success twisting the throttle 24 times on an fcr to start a crf450x. Normally, you need to keep your hand off the throttle. We often tell people to literally move their hand off the throttle tube and rest it on the master or something.

Important question here: when you say that it starts pretty easy now, is that a cold bike? If not, don't count your chickens just yet.

Don't worry about the glowing header, just don't let it sit and idle so long that-that happens. Let it idle for 30-60 seconds and then start putting around until it's warm.

Best to sort out the jetting by symptoms, especially when you get into aftermarket jet kits and different taper needles.
Click to expand...

Thanks for the input on the hot exhaust.

Yeah, after 24 twists of the wrist she fired on second or third kick. As the old owner had some what neglected the carb, and the massive amount of throttle input to start, my first inclination was clogged jets. So I started with a carb clean up. I could barely see through the 162 main jet that was in it. So I put a fresh 162 in the main and cleaned the slow jet. The only reason I did not go to a 165 main as recommended by the JD Jet Kit was that the airbox and exhaust are not opened up, so I decided to stay a bit leaner and follow the jetting the mechanics at Peninsula Honda had put in for the original owner.

The previous owner had some work done on the carb. The accelerator pump linkage is not like anything in the manuals or photos and the accelerator pump cover looks like it could be a Quick Shot.

Easier to start cold. No choke only 3 twists of the throttle and fired after just a few kicks. I will fire it up again tonight and take it for a spin to see how she is running.

I will be check the valves, but am also considering a better cleaning of the carb and TPS setting, then go from there.
 
byke

byke

Well-known member
Super weird. Once your bike is jetted correctly, you'd never get it started that way. That's exactly what you'd do if you never wanted it to start.

You might consider buying a few new pilots. If it has some tarnish inside, spraying it doesn't work and your 42 becomes a 38. I have some solid core 30 gauge wire I run through the little holes and even that isn't perfect sometimes.

Generally speaking, you should never mess with the TPS. If you're ever unsure about it, just disconnect it, because it doesn't seem to actually do anything. I'm not sure if a poorly adjusted TPS is worse than a disconnected TPS, so I'd disconnect it for troubleshooting.

If it starts without the choke, even with priming, I'd guess the pilot is two sizes too big. It would probably idle a little worse when warm and a quick test would be to screw the fuel screw in all the way while it's running, assuming you have an externally adjustable fuel screw. If it doesn't die when screwing it all the way in, then the pilot is too big.
 
budman

budman

General Menace
Staff member
Good to see you back Dave.
I still have my Laguna T2 avatar you made me.
Throw it out now and again.
 
budman

budman

General Menace
Staff member
:laughing

Somewhat wiser I would believe.
Holding on to our youth has some value for sure.
 
PASTAPWR

PASTAPWR

Well-known member
Quick update.

Came home from work and started her up.
My truck showed ambient temp to be 51F
My garage door panels showed garage temp as 67F

She started on second kick with choke and no throttle. Had to kill choke very quickly.

She ran up and down the street pretty well, but still seems to be running hot.

I do have external fuel screw and did some idle/fuel adjustments. She started to stumble as I turned fuel in, then again as I turned the fuel screw in. I set it 1/2 way between the two. Will get an exact number this weekend. Throttle rolls on smooth, but has some bog during blipping. Still some fine tuning to do on the carb, but I think at this point it is close.

Also on agenda for weekend is to flush and replace the coolant.

Have already done oil, trans, plug, and air filter. Wheel bearings, swing arm bearings and head bearings all pass the wiggle test, so will not worry about those right now.
 
byke

byke

Well-known member
Sounds like you're getting it. And don't sweat bog on the stand, just make sure it doesn't bog when riding.
 
Butch

Butch

poseur
Staff member
Wool, let’s go riding. Though some drying might be good. Joining us for StonyBARF?
 
PASTAPWR

PASTAPWR

Well-known member
Butch said:
Wool, let’s go riding. Though some drying might be good. Joining us for StonyBARF?
Click to expand...

Just read through the thread and Storyford 9 thread. This looks very interesting. Will look at the dates and how it lines up with school schedule for my son. It for sure sounds like a great time.
 
PASTAPWR

PASTAPWR

Well-known member
280SQUAGGLER said:
Dude where you been ???? Good to see you again !!!! Shoot me a call or stop by sometime
Click to expand...

Hey!!! I have been working and raising kids. For the last 2 years I have been obsessed with better health. All my time has been spent in the gym and researching nutrition.

My kids are getting older and my son loves active sports so we have been snowboarding the last few seasons and just picked up some used Honda dirt bikes to begin enjoying some dirty BARFing.

I'll have to stop by your shop. Glad to see thing seem to be going well for you.
 
PASTAPWR

PASTAPWR

Well-known member
Update on the 450X.

She fired right up with choke, no throttle, on third kick today. Garage was 60F or lower at the time.

Valves are in spec and on the loose end. 0.010 IN (both), 0.005 EX (both). Adjusted decomp clearance while I was in there.

Finished all fluid changes since I bought her used.

Fresh oil, trans, air filter, brake fluid (front and rear), coolant.

She is running cooler now, well it may also be cooler today, but the pipe although it did get hot, did not get hot as far from the head as before.

She pulls pretty hard through all gears and can easily power wheelie in second gear. I am happy at this point and just waiting for a bit of dry weather so we can get out to Metcalf.

Thanks to all that weighed in with advice.
 
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