CRF 450X Question...

[The Cardinal]

It's our first year running a single and we've been pulling the engine apart a lot on the dyno stand trying to work out the kinks of fuel injection. Now it when it does manage to start it sounds like the timing is way off, but we've checked that multiple times and it's fine. I fear that we may have gotton some spark plug wires crossed in our hasty re-assembly and was wondering if anybody know the firing order of this engine off the top of thier head.

Any help is much appreciated.
Thanks in advance.

[The Cardinal]

It's our first year running a single and we've been pulling the engine apart a lot on the dyno stand trying to work out the kinks of fuel injection. Now it when it does manage to start it sounds like the timing is way off, but we've checked that multiple times and it's fine. I fear that we may have gotton some spark plug wires crossed in our hasty re-assembly and was wondering if anybody know the firing order of this engine off the top of thier head.

Any help is much appreciated.
Thanks in advance.

[Mbirt]

This is a tough one, but I've got it.

It fires when its one piston approaches TDC every other rotation of the crankshaft.

When you time it, make sure you're looking at the outer dot down at the crank end. It's more difficult to see than the one further inboard toward your allen key.

[Ockham]

The sarcasm meter, Cap'n! We're oof the scale!

[Adambomb]

#1 should go to the spark plug, #2 to the flamethrower exhaust, #3 to the driver's seat for non-visual over-rev indication, and #4 in parallel with #1 for super-mega-wasted spark. http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[kracer]

Interesting question.
Sarcasm aside, I've heard, when starting out, try to master fuel injection only first, and run the stock ignition components.
Standard spark w/ EFI.

[Andrew_UTA]

The firing order for the CRF450X is 1-1-1-1-1. http://fsae.com/groupee_common/emoticons/icon_biggrin.gif

[Kirk Feldkamp]

I realize this is a joke post, but I'm sure someone in the future will see it and not get it. For that person in the future...

Once you get it running, keep it running, and be ready with a timing light. There should be some timing marks described in the manual that you can check your advance against.

What ECU are you using? Some systems deal with varying cranking RPM better than others. Big singles have a reputation for having relatively inconsistent cranking speeds because things slow down so much at the top of the compression stroke. Also, your trigger tooth counts and consistency can make a big difference. If you added a cam sensor, make sure it's solidly attached and doesn't move!

[Mbirt]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by kracer:
I've heard, when starting out, try to master fuel injection only first, and run the stock ignition components.
Standard spark w/ EFI. </div></BLOCKQUOTE>In all honesty, this is an excellent way to go. Why not run the stock carburetor? My experience tells me that, with a carb ahead of the restrictor and a necessarily small plenum volume (or lack thereof) for startability, a CRF450X will make a maximum of 25-32 hp at redline. An intake design which deals pulse-by-pulse restrictor choke is crucial. This will likely require fuel injection... but not programmable ignition.

Does nailing down a perfect ignition map get you an extra horse or two and better throttle response? Sure. But that's nothing like the 20 hp the intake and requisite fueling system can bring.

[Jaaps]

Hey, way off topic. But does anyone know where I could possibly get a solidworks model of WR450X. Sorry if this isn't the place to ask these things, but I've ran out of places to look and can't find anything. If anyone have a model can you email it to me... jakob.badenhorst@connect.qut.edu.au

Cheers everyone
Jakob

[kracer]

Jakob,

it is best to keep questions to a single thread.

[vikram.]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Mbirt:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by kracer:
I've heard, when starting out, try to master fuel injection only first, and run the stock ignition components.
Standard spark w/ EFI. </div></BLOCKQUOTE>In all honesty, this is an excellent way to go. Why not run the stock carburetor? My experience tells me that, with a carb ahead of the restrictor and a necessarily small plenum volume (or lack thereof) for startability, a CRF450X will make a maximum of 25-32 hp at redline. An intake design which deals pulse-by-pulse restrictor choke is crucial. This will likely require fuel injection... but not programmable ignition.

Does nailing down a perfect ignition map get you an extra horse or two and better throttle response? Sure. But that's nothing like the 20 hp the intake and requisite fueling system can bring. </div></BLOCKQUOTE>
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