[Ride_Red626]

I am going to be buying an HRC end cap and at the same time im going to be removing the air box lid. Just wondering what is a good "starting" jet. I live in Arizona and our elevation is about 1100 with temps well over 100 I did a search and other people's jetting is all over the place so I figured I would ask as I know some guys here are from AZ.

Thanks
Dave

 

[WhiteZee]

i would start with a 170 main jet.

 

[Ride_Red626]

That’s what I was thinking as well but got a little confused when I saw people were running all the way from 160-198 with the same mods...

But I will give it a go and see what happens.

Thanks
Dave

 

[Novanuttz]

I am running the same setup as you and I use the 180 here in Tucson 2600'and it runs well, I would go for the 185 in Phx.

 

[Ride_Red626]

How about at the dunes. That is mainly what I am looking for. I would prefer it to run a little rich in town (can fine tune it with the air screw) and run good at the dunes rather than be lean down there?

Dave

 

[Ride_Red626]

Well I installed an HRC end cap, removed my air box lid and bumped the main up to a 180 for now. As you know I am in the Phoenix area.
But anyway here is my dilemma...
I have not rode with the mods yet, but started it up and let it warm up for a few mins (maybe 5 or 6 minutes) then gave it a couple blips of the throttle to clean it self out and rode up and down the street. There seems to be a slight bog off of the bottom? Like I said I have not ran it yet just putted up and down my street. But did I go to big on the main jet?

Also with these mods and jetting will I be alright at the dunes, or will I need to re jet when I go down there. Our elevation in town is about 1100 or so, the dunes are right around 400, and I do some riding up north and the elevation is anywhere from 3000-8500. I ran it in bone stock form this past weekend at Mingus Mountain (about 8000 ft) and it ran pretty good, but actually felt lean at about 1/4-1/2 throttle? When I removed the baffle/stock end cap it was VERY VERY black and looked as though it had been running very rich...

My last question for now is does the HRC end cap make it sound like it is running in a garbage can? I cant exactly tell if it is popping on decel of RPM's or if that is what the end cap sounds like?

Thanks
Dave

 

[TRX450rlude]

Originally posted by Ride_Red626@Aug 3 2004, 08:40 PM
Well I installed an HRC end cap, removed my air box lid and bumped the main up to a 180 for now. As you know I am in the Phoenix area.
But anyway here is my dilemma...
I have not rode with the mods yet, but started it up and let it warm up for a few mins (maybe 5 or 6 minutes) then gave it a couple blips of the throttle to clean it self out and rode up and down the street. There seems to be a slight bog off of the bottom? Like I said I have not ran it yet just putted up and down my street. But did I go to big on the main jet?

Also with these mods and jetting will I be alright at the dunes, or will I need to re jet when I go down there. Our elevation in town is about 1100 or so, the dunes are right around 400, and I do some riding up north and the elevation is anywhere from 3000-8500. I ran it in bone stock form this past weekend at Mingus Mountain (about 8000 ft) and it ran pretty good, but actually felt lean at about 1/4-1/2 throttle? When I removed the baffle/stock end cap it was VERY VERY black and looked as though it had been running very rich...

My last question for now is does the HRC end cap make it sound like it is running in a garbage can?  I cant exactly tell if it is popping on decel of RPM's or if that is what the end cap sounds like? 

Thanks
Dave

If I were you I would use either the 185 or 190 main jet....If you want to take care of the bog from down low then you need a bigger pilot jet...I just learned to live with it........I had that same set up for a while...I ride in the sand in Oklahoma and the setup ran great for me....I ran a 185 but Im going up to a 190

 

[Red Rebel]

Ride Red626

It may just be me, but I think you may be running a little too rich. If I'm not mistaken, you said you were running just the HRC end cap and lid off, with a stock air filter. In my opinion you should be running around 168 to 170 tops at Phoenix elevation.
I ran my 450r with a 168 jet at glamis with the same setup you have now, back in april, and she ran great. No bogging, no hesitation, no flubbering, and no over heating. That worked good for me, but every bike is different. Elevation and ambient temperature all play a part in jetting.

Hopefully this will help you come up with a range of where you want to be jet wise.
We are all lucky fourstrokes are pretty forgiving when it comes to jetting.

Good luck!!!

 

[Ride_Red626]

Ya I would definitely be a little rich than lean with out temps. So with the HRC needle I should run it on the 3rd clip position, with a 190 MJ, air screw about 2 - 2 1/4 turns out and keep the stock pilot?

I will have to run it how it is right now and see what it runs like. Like I said I have yet to leave my street with these set ups, and jetting it in the garage is not the way to go but had a few questions. I will put the HRC needle in... if I can find one... and then I will let you know where I am at.

Thanks again guys
Dave

 

[GOTIS]

JUST A HEADS UP.. I RUN THE HRC KIT AND FULL SPARKS EXH. I HAVE A 190 MAIN ...3RD CLIP POS. THE BIKE RUNS FLAWLESS AT 4 PEAKS...GLAMIS....AS WELL AS PINETOP WHICH IS 6800FT....OH ALSO IM AT 2 1/2 TURNS OUT ON PIOLET......HOPE THIS HELPS

 

[Novanuttz]

Yes you can get the HRC needle but you have to get the needle along with the 185 main jet $30.00. OUCH .

 

[Ride_Red626]

Well I can't seem to find an HRC needle? Everyone keeps telling me that they don’t sell the needle separately. But does anyone know if I change the stock needle to the 3rd clip position will it run weird? Is the HRC needle that much different.

Thanks
Dave

 

[Ride_Red626]

Lol, well I may be looking into getting a full system now. I had a CHM on my CRF450 and it ripped. I will more than likely get the CHM for my TRX as well.

But I will go run it with the 180 and see what it feels like and ill report back if I have any questions.

Gotta love places like this so you can ask a question and get so many responses. :lol:

Thanks again guys
Dave

 

[Red Rebel]

(the cam doesn't change jetting significantly except for the air screw (idle to 1/8) ...

[/quote]
Now I maybe wrong and someone can correct me if so, but an engine is just an air pump. The more air in and out, the more hp. Cams definately changes the duration of the valves opening and closing, thus the air to fuel mixture has to change.

I agree, it is better to run too rich than too lean, but I still believe running a 190 main jet with just an HRC end cap and air lid off is too rich.

The only way to really find out is to jet it up til it sputters than back it down.
Then run it wide open, shut it off, and pull the plug. (not an easy task)

You'll just have to rely on the info you get from this thread.