exhaust core

[Eddiesanders250]

i tried searching for it, no luck... ive tried removing the spark arrestor, of course without re jetting doesnt run worth a chit.... have u guys experimented with this at all??

what pipe you talking about? Stock dont have core, stock uses baffles.

were the exhaust flows thats the core. The circle thing that goes from the front to the rear of the pipe.

[Eddiesanders250]

sry im talking about removing the baffle.....

Originally posted by Eddiesanders250
sry im talking about removing the baffle.....

So baffle or spark arestor and in what pipe?

[Eddiesanders250]

sry im not being too clear... i want to remove the baffle in tge stock pipe to increase airflow because it is so restrictive... and when you take that baffle out you have to change the jetting possibly airfilter..... i was wondering if anybody knew off the top of their head what jet to use??

[ghott]

They make an HRC Endcap for this specific purpose...it rids you of the peashooter baffle, and you have a nice shiny new endcap with a spark arrestor still there. I used on on mine for a couple months...got it off eBay for about $45. I'd say you have to bump the main jet a couple sizes...but it depends on what year R you are using...the 04/05 carbs are different from the 06/07 carbs.

I think your talking about the spark arestor. When you pull it out you dont really need a rejet cause it dont make it flow much more over stock. The amount of extra flow you gain is not going to really be felt other than it will rev faster and be slightly louder.

Drill a 1" hole in the steal wall in the muffler and it will be 100% better over stock and sound pritty good. The steal wall you can see after removing the sparky.

This is how the inside of stock mufflers are after you get past eht steal wall. I blocked all the pipes up but 1 and it felt nearly good as my white bros pipe but a lil loud, or more like alot loud.
http://i108.photobucket.com/albums/n26/getdrunk1990/4wheeler195.jpg

[fandl450r]

Originally posted by Dhumpalo
I think your talking about the spark arestor. When you pull it out you dont really need a rejet cause it dont make it flow much more over stock. The amount of extra flow you gain is not going to really be felt other than it will rev faster and be slightly louder.

Drill a 1" hole in the steal wall in the muffler and it will be 100% better over stock and sound pritty good. The steal wall you can see after removing the sparky.

This is how the inside of stock mufflers are after you get past eht steal wall. I blocked all the pipes up but 1 and it felt nearly good as my white bros pipe but a lil loud, or more like alot loud.

No Slow, I'm pretty sure he's referring to the baffle, which in stock pipes acts as a spark arrestor. If you do remove the baffle the Ghott said it might be a good idea to go up some main jet sizes, and maybe run with no lid.

Originally posted by fandl450r
run with no lid.

That meens pilot change. Get the main jet set right b4 removing the cover. Makes jetting much easier.

[ghott]

Originally posted by Dhumpalo
That meens pilot change. Get the main jet set right b4 removing the cover. Makes jetting much easier.

Not if he is running the 04/05 machine.

Lid off + HRC Style end cap on a 2004 or 2005 450R requires a 185 main jet, 2.5 turns out on A/F Mixture screw, and the STOCK pilot jet.

If he is using the 2006 or 2007 450R....its a different story.

In all honesty, we need more info from the topic poster.

Originally posted by ghott
Not if he is running the 04/05 machine.

Lid off + HRC Style end cap on a 2004 or 2005 450R requires a 185 main jet, 2.5 turns out on A/F Mixture screw, and the STOCK pilot jet.

If he is using the 2006 or 2007 450R....its a different story.

In all honesty, we need more info from the topic poster.


I was thinking he had a 400ex. oopsys

[fandl450r]

Originally posted by Dhumpalo
I was thinking he had a 400ex. oopsys

Hmm weird this thread is in the TRX450R forum.

And as Ghott said if he has the 04/05 the pilot doesn't need to be changed.

[Eddiesanders250]

lol no 400ex 06 450r..... what does hrc reccommend for jetting when you put their end cap on.. bump up a couple sizes in the main... what did you use as far as jetting?

[roundsy]

on my 06 i took the baffle out but left the spark arrester in, its a bit of a different sound, not loud but loud enough to hear yourself over the engine, I used an 05 crf needle on the third clip, 165 main, left the pilot at stock 42 and dropped to a 55 leak, its gotten colder here so im going to go up to a 168 and try that but it ran mint with the 165 in summer/fall...btw thats with no lid and a uni fiter as well