main jet question

[brandonracing01]

I have a 05 trx 450r with a full yosh pipe sys. Just put in a hrc kit do i need to run a bigger main jet then the 185 they give you. If anyone has a full pipe sys with the hrc kit please tell me what your running so it will help me out. I do also have a k&n filter to but thats about it!

[ricks450]

Remember this always, start off rich, Work your way down . Put a jet in there that will make the motor run rough. Work your way down from there. No two motors make the same power. Start with a big jet like a 195 or 190 . work your way down in 5 degree inc. 195 190 185 180, The first jet that starts making the motor run good and responding good you know your good . Richer is always better than lean. It can cost a lot of $ to be to lean.

[brandonracing01]

thanks for your comment but i do know that you always want to be richer than leaner i just want to know what people are runing with the hrc kit and a full pipe sys please let me know 185 is with hrc kit so run 195 or 190 or keep it the same?

[ghott]

Each pipe will be different.

At one time, I ran the HRC Kit with a 185 main.
I added a HMF Full Exhaust, and I had to drop my main to a 180.
Then I took off my HMF pipe and added a DASA pipe and had to go to a 190 main.

Use your butt dyno and see what feels best to you.

[ricks450]

It is not good to be way to rich. If you start off rich work your way down to a jet, that the bike starts reponding to. And your A/F screw on the carb is making a differance when you turn in and out. That's where you want to be. This is what happens to a motor running to rich. It will glaze your cylinder causing your rings not to seat. It will knife edge your rings, besides carbin build up. You can replace your rings, hone your cylinder, and clean carbin and put motor back together. If your to lean plan on replacing your top end. Your piston can get so hot it will swell up and seize in your cylinder . I would hate to happen. Are you runing stock carb?

[ricks450]

Originally posted by ricks450
It is not good to be way to rich. If you start off rich work your way down to a jet, that the bike starts reponding to. And your A/F screw on the carb is making a differance when you turn in and out. That's where you want to be. This is what happens to a motor running to rich. It will glaze your cylinder causing your rings not to seat. It will knife edge your rings, besides carbin build up. You can replace your rings, hone your cylinder, and clean carbin and put motor back together. If your to lean plan on replacing your top end. Your piston can get so hot it will swell up and seize in your cylinder . I would hate to happen. Are you runing stock carb? I ran a hotcam stage2, full duncan exhaust, 11.5 to1 piston with no airbox lid with proflow filter on a stock carb and ran a 190 main. It ran good on all that. So it would be good to try to do it yourself. If your runing stock carb IMO throw it in the trash and get something else they suck.

[ghott]

LOL.

There is nothing wrong with the stock carb.

Spend the $400-$500 elsewhere.

[Architects]

Originally posted by ricks450
If your runing stock carb IMO throw it in the trash and get something else they suck.

WPP is getting 54 Hp off the stock carb on there 05. Granted a FCR is better the money would be better spent else where.

[ricks450]

The idle curcuit in the 05 carb is actavated off the vacume of the engine. when you give the bike gas it switches to the main curcuit (MAIN JET).when the motor is idleling it has full vacume. SO when you put a big cam with alot deration in the motor. That goes away. So it makes the bike hard to get to idle. the idle adjustmet worthless. Unless you drill your slow jet which sucks IMO. I want something you can adjust not only the idle of the bike but the idle curcuit to(SLOW JET). IMO. I have a stage2 cam, 11.5 to1 piston, duncan full exhaust and airbox lid removed making over 50 horses, with the stock carb. But it still sucks

[ghott]

I run a Hot Cams Stage 2 with the stock carb, and have 0 idling problems. I have no problems adjusting the idle either.

Brian @ WPP (54HP stock carb), uses a WEB 943/921 Cam, 14:1 Piston, and Ferrea Superflow Valves and has no problems with idle adjustment either....

No jet drilling required.

[ricks450]

The bike will idle to low or to high. No offence here ghott. What does your bike idle at? What rpm?

[ghott]

I do not have a tiny tach, so I dont' know what my idle is currenty set at. And the last time I was at the dyno, I didn't pay attention to what the idle was set at either...

I know I don't have problems adjusting my idle, it will idle wherever I want it to...not too high or not too low.

Your case is the first that I've heard about a weird idle. I'm not saying that you're information is false at all. If you have this kind of problem, then there is no reason someone else couldn't have this type of problem.

[ricks450]

Mine either idles to low or to high . I like to keep my idle around 1750 to 1800 hundred to get away from lopping when engine is idling to low from the daration on the cam. but the damn thing swicthes from idle curcuit to main curcuit. Right around that like 1850. And as soon as I touch my idle adjustment it jumps from around 1800 to 24 or 2500 rpms.