[bugslayer]

Hi all, I've been searching this and other VTX boards and I can't seem to get a straight answer. I have a 2003 1800c and will be putting on a set of Hard Krome 3" Big Straights and a Thunder Hurricane air intake system. I'm doing this mostly for style. If I got more power that would be awesome but I'm pretty happy with the power just as it is. My main objective is that I just don't want to loose any power by adding the pipes and intake. Some say the bikes on-board computer will automatically adjust to the mods so I don't need to do anything more. Others say if I make these two mods I MUST add a fuel management system like a Cobra or Power Commander. Others say if you add a fuel management system, you have to get an O2 sensor or the unit won't really do anything.

So knowing I'd love to add power, but would be perfectly happy just keeping the power I have, what's the ideal set up? I already have the pipes and the intake so I can't change those. If I can get an informed answer that gives me the "real" facts based on experience, I'd be super grateful.

Thanks!

Ben
"bugslayer"

 

[Vinish]

It is impossible to answer your question because every bike is a little different and every setup is unique in its own way. Try just the pipes and air cleaner change and see what happens. Do you have good cold start, good power throughout the rpm/speed range, good fuel economy (at least good for the VTX1800 guzzler)? If so, no need for a fuel manager. If problems arise, a fuel manager is your next step.

 

[bugslayer]

It is impossible to answer your question because every bike is a little different and every setup is unique in its own way. Try just the pipes and air cleaner change and see what happens. Do you have good cold start, good power throughout the rpm/speed range, good fuel economy (at least good for the VTX1800 guzzler)? If so, no need for a fuel manager. If problems arise, a fuel manager is your next step.

Thank you for taking the time to answer. I appreciate it. But I have to think there are some pretty consisstant factors here. The 2003 VTX 1800 engine, the Hard Krome big 3's and the Thunder Hurricane air intake. Those are a common combination. Someone out there must have be running this set up and can comment on what they found.

I'll do the pipes and air intake as you suggested and see how it goes, but I'd really appreciate someone who has run this set up sharing with me what they needed to do for optimal performance. In my past experience with jetted carbs (which I know my bike does not have), when you push more air through the engine via upgraded air intake and free flowing pipes, re-jetting was not an option, it had to be done.

It's sort of hard for me to imagine I can do these mods and not have to do something to help the engine perform at maximum potential without some sort of change. Don't get me wrong, I don't want to spend $300+ on a fuel manager and even more on an O2 sensor, but I'm not willing to compromise. I want my original power++ and maybe even better throttle response. (smoother and less jerky).

Those who know, please help with your comments.

Thanks very much!

Ben

T

 

[PaXman11]

I run the HK 3", but a modified stock intake that has had extra holes drilled into the front inner of the airbox and dyno'ed by the P.O. -and- a PC III. General rule when changing intake, if you want better performance (read: more HP, since you will sacrifice mileage), you will want a fuel manager of some kind. Just changing exhaust you don't really need the fuel manager, the stock box will adjust.

 

[RenegadeRick]

Some might argue with me, but most of the HP gains from intakes and exhaust mods can't really be felt by seat of the pants testing. You would need need a dyno to measure the gain or loss if any. Exhaust , intake , fuel manager, etc. is only a few HP gain. It does give you bragging rights and a sheet of paper to back it up.

 

[Duug]

I did some air/fuel/exhaust mods to my XC mainly to help smooth out the power band from all the hiccups and surges the OEM tuning had hobbled it with. I added Thunder air kit and RHShorty exhaust along with a beta TFI by Dorbeck.
Rather than monkey with trying to tune it myself,...I took it to a moto wrench with a dynometer. He ran it the first time for a base line,..87 hp and the fuelix was all over the board. Then it took 3 more runs to dial it in to nearly constant 13/1 A/F mix and a result of 102 hp.
Quite frankly I didn't really care or notice the increase in torque at first but, it sure runs ALOT smoother and throttle response is spot on.
As for added boost in power,...it's clearly evident when paired up to other 1800 Xes.
Bad news is the fuel mileage dropped from 147 miles per tank to 115.
Overall,...It's been well worth the cost as it's an absolute blast to ride instead of a chore.

As for which fuel manager to buy,...keep in mind,...the VTX only needs fuel added so a digital manager will work just fine.

 

[Silver F]

first your bike has first generation computer... 2005 has the upgraded one.. even the connectors are different.

exhaust and air intake Needs more than Honda can provide in its computer.... LEAN BURN is the FORCE OF THE EPA....

and a dyno is a MUST.. even just to get the VTX to run nice.. cold, warm, hot... without question... POWER is small and costs a lot.

price of exhaust, intake, reprogrammer, dyno time, mechanic time...ETC.

I am from the CBR1000F world (including Track Time) 155 plus mph ... and my stock VTX is fine with me.. and has been for 11 years how.

its your money and time... and the VTX will NEVER be fast... there is a guy in England that sells a bolt on Supercharger for your VTX.

 

[Duug]

Fast is a relative term. The X is good for an indicated 144 mph which is "fast" enough for me.
From a standing start My Xc covers 100 yards quick enough to leave almost anything behind long nuff to give a contender pause to ever try it again. Especially at a Bike Nite situation where cash bet on short hole shot races.
Years ago I had a HOnda Blackbird. THAT bike was top end fast but, still not quick nuff to pull away from the first VTX I ever saw off a dead stop. That's why I bought one.

I agree the only practical reason to do a/f mods is to make the bike ride more smoothly and correct the lean mix it has from the factory on the low end.

 

[bugslayer]

Thanks. That's the best answer I've seen. Very informative.

 

[jjud13]

I have an 1800R with hk3's and a modified air box with k&n. Very similar to your setup. Rode the bike like that for over a year in every elevation east of the Mississippi. Ran like a top. I recently put a cobra power pro on the bike (got sucked up in all the hype). Put a couple thousand miles on it. Did it help with power? Maybe. Did it smooth out the throttle? Yes!. Gas mileage didn't change. So you don't "need" a fuel manager. The better question is, do you WANT one. For me I don't think it's worth the price for the particular one I got...but... I do like what it does to the x.