[brettp]

Harkon, great observation-am disappointed I did not think of it myself. Always fun to find out turn the screws and see what the engine sounds like. May need to connect ground wire first. Not sure it's powered on with the black wire disconnected. I recall from a video, when the hypercharger is installed, the idle control on the left side of the engine is disabled-not convinced just yet, that's true. Have to get a closer look with a flashlight. So maybe if there are adjustment screws... Maybe it's part of the Kuryakyn intake kit(?) Again, fun to find out. Thanks

If I'm right, the idle on the 1800 (being fuel injected) is adjusted by increasing or decreasing the air intake on the manifold. And it is mechanical, not electrical. I don't know anything about the hypercharger installation but I can't imagine the stock idle adjustment being disabled

 

[TPVTX1800]

Found the following source for VTX circuit diagrams for others, like myself, who do not have good documentation and rely on PDF manuals from the internet. In my case, a series of very granular PDFs.

Motorcycle Wire Schematics | Bareass Choppers Motorcycle Tech Pages

This is a collection of motorcycle wiring schematics to aid in understanding and troubleshooting electrical systems and problems on your bike.

tech.bareasschoppers.com

 

[Chicago-Spike]

Yes, BareassChoppers and many other great tools can be located on the How To;Step-by-Step board. We've known Bare around here since he joined way back in 2002

 

[TPVTX1800]

Yes, BareassChoppers and many other great tools can be located on the How To;Step-by-Step board. We've known Bare around here since he joined way back in 2002

Yeah, that was my DUH moment. Had to share though!

 

[Harkon]

Harkon, great observation-am disappointed I did not think of it myself. Always fun to find out turn the screws and see what the engine sounds like. May need to connect ground wire first. Not sure it's powered on with the black wire disconnected. I recall from a video, when the hypercharger is installed, the idle control on the left side of the engine is disabled-not convinced just yet, that's true. Have to get a closer look with a flashlight. So maybe if there are adjustment screws... Maybe it's part of the Kuryakyn intake kit(?) Again, fun to find out. Thanks

It won't adjust for sound, just the fueling at different RPMs. It's like a jet kit for carburetors, only for fuel injection. It's really not needed but many have used them to adjust put the decel popping. It is very important one doesn't just make indiscriminate adjustments. It is important to know what each adjustment does and why you'd change it.

It looks a bit like this,

TFI - Electronic Fuel Injection Controllers - ATVs, UTVs, Motorcycles, Sport Bikes

But by the wiring it's not identical so God only knows what you've got there.

 

[TPVTX1800]

In fact I just got back from digging into the box, yes it's a Techlusion E199143 v94-0 0538 (ckt board marking) same as Speedy on this forum post from a while back. Will look for the instruction on TFI website. Thanks for your effort. Also pulled the left side plugs-oily, and wet. I guess it's running rich hence the backfire

 

[brettp]

Nice! Finding symptoms is half way to finding a solution. Curious to hear more as things progress.

 

[TPVTX1800]

Nice! Finding symptoms is half way to finding a solution. Curious to hear more as things progress.

Thanks, internet makes things doable. I found the install sheet for the TFI FI-2050ST fuel adjustment thingy (not sure it's called a power commander?) including the recommended settings for both VTXs and other large displacement V-twins. Just realized, from the ckt board pic above, for the 1800 the settings are WAY OFF-will need to adjust-I hope it still runs okay. Should be at 3:00, 3:00, 1:15ish and 3:45ish (Green, Yellow, Red, rpm)
Should be decent weather tomorrow, so am planning to ride for a bit, then check plugs again. Yeah, it's New England and I'm a fair-weather rider (read wimp/not hardcore).

Oh, and one other thing: I couldn't adjust the idle with the screw on the left side of the engine-this lends some credibility to the video I mentioned. If this is the cause am really not liking the Kuryakyn.

 

[Fulkrum]

Oh, and one other thing: I couldn't adjust the idle with the screw on the left side of the engine-this lends some credibility to the video I mentioned. If this is the cause am really not liking the Kuryakyn.

My 1800c has a hypercharger and I am able to adjust the idle via the screw/cable on the left side of the engine

 

[TPVTX1800]

My 1800c has a hypercharger and I am able to adjust the idle via the screw/cable on the left side of the engine

Aha! Good to know- thanks for the info. Okay, I have to check it out some more-guessing I'm somehow doing something wrong. Maybe the TFI is messing up something?

 

[Fulkrum]

Aha! Good to know- thanks for the info. Okay, I have to check it out some more-guessing I'm somehow doing something wrong. Maybe the TFI is messing up something?

You could always temporarily remove it from the system to eliminate the variable while you diagnose. I kinda doubt it is the cause of your inability to adjust idle but it would be simple to find out. Mine has a Power Commander 3 on it and I am still able to adjust the idle

 

[TPVTX1800]

You could always temporarily remove it from the system to eliminate the variable while you diagnose. I kinda doubt it is the cause of your inability to adjust idle but it would be simple to find out. Mine has a Power Commander 3 on it and I am still able to adjust the idle

Will give it a shot. Cheers!

 

[Chicago-Spike]

That TFI is so old I would just take it off and toss it. It's probably not doing anything right, electronics go bad all the time and that is an antique. It's not a PowerCommander, that's made by DynoJet and is much, much better peice of electronics as it both adds AND subtracts fuel from the curve. The TFI only adds. If you do keep it, and I don't know how it adjusts, try settings that are a little bumped up to the positive on the idle pot(green I'll guess ) and the last 2 pots set at zero as the VTX runs rich at the mid and upper RPM range.

As for the idle adjustment, pull the knob out a little bit and then turn it

 

[TPVTX1800]

That TFI is so old I would just take it off and toss it. It's probably not doing anything right, electronics go bad all the time and that is an antique. It's not a PowerCommander, that's made by DynoJet and is much, much better peice of electronics as it both adds AND subtracts fuel from the curve. The TFI only adds. If you do keep it, and I don't know how it adjusts, try settings that are a little bumped up to the positive on the idle pot(green I'll guess ) and the last 2 pots set at zero as the VTX runs rich at the mid and upper RPM range.

As for the idle adjustment, pull the knob out a little bit and then turn it

Just got back from the ride and without the TFI. The VTX feels really, really willing to launch me (us) into the next county. I have temper my clutch and throttle actions for big power-woohoo! If you see me lurking around the forum every day or two, you'll know I'm still alive. As for the TFI, I set is for 3, 3, 1, 4(- 4th pot is for rpm) and tucked it away for now. I may install at some point if I get curious. Oh, and thanks for the pull and turn instruction!

 

[TPVTX1800]

Alright Gents, here is the last entry for my exploration into the two apparent topics: fiberglass repack of the stock exhaust, and the TFI ancient artifact of a fuel controller. Took off the upper muffler and found disassembly to be either not possible or involve too much time and/or risk to explore any further-so I'm dropping the task. It might cringe a few of you to learn that I reinstalled the TFI with recommended settings for the VTX 1800, and to my surprise, the VTX seemed sounded a little less raspy-marginally a little 'better' (the more delicate neighbors and my 'eye balls' will just have to put up with the sound). So far no dirty looks-most just confused looks. This area is not motorcycle country. I previously mentioned the TFI ground wire was not connected, so when I connected the ground, the LEDs came on so the unit seemed to work okay. I can deal with the VTX as is, for the immediate future. Want to get at least a few hundred miles in the saddle before I consider maybe upgrading to a DynoJet.

Gents, thank you for the advice, insight, and commentary-it is very encouraging to know enthusiastic help is available! Cheers!

 

[brettp]

Enjoy the miles! You're going to love it!

 

[Harkon]

Alright Gents, here is the last entry for my exploration into the two apparent topics: fiberglass repack of the stock exhaust, and the TFI ancient artifact of a fuel controller. Took off the upper muffler and found disassembly to be either not possible or involve too much time and/or risk to explore any further-so I'm dropping the task. It might cringe a few of you to learn that I reinstalled the TFI with recommended settings for the VTX 1800, and to my surprise, the VTX seemed sounded a little less raspy-marginally a little 'better' (the more delicate neighbors and my 'eye balls' will just have to put up with the sound). So far no dirty looks-most just confused looks. This area is not motorcycle country. I previously mentioned the TFI ground wire was not connected, so when I connected the ground, the LEDs came on so the unit seemed to work okay. I can deal with the VTX as is, for the immediate future. Want to get at least a few hundred miles in the saddle before I consider maybe upgrading to a DynoJet.

Gents, thank you for the advice, insight, and commentary-it is very encouraging to know enthusiastic help is available! Cheers!

Another few things to look at when you have the inclination. The pair valve removal changes the sound a but at idle and cleans up the top of the engine. It helps with decel pop as well. Do the ground fix. It really helps with spark and fueling, keeping it running smoooooth. Keep the heel toe shifter pivot lubed. It's been known to bind when it gets dry. Just a bit of grease once in a while.

 

[TPVTX1800]

Another few things to look at when you have the inclination. The pair valve removal changes the sound a but at idle and cleans up the top of the engine. It helps with decel pop as well. Do the ground fix. It really helps with spark and fueling, keeping it running smoooooth. Keep the heel toe shifter pivot lubed. It's been known to bind when it gets dry. Just a bit of grease once in a while.

From the YouTube videos I reviewed, the topics you state are for now further down the list of improvements. I'd like to desmog the bike for the results you mention-am a little concerned emissions may not pass inspection-not sure desmogging will have an effect. First on the list to install a fuel line quick disconnect with dual shutoffs to make tank removal easier (less messy). Then do the ground fix, and for access to the pair valve & coolant fill. Lots to do. Just not all at once. Thanks!

 

[Merry Prankster]

Check your Rubbers.....
Side Covers, Bushings, ETC.

 

[rangers4u]

From the YouTube videos I reviewed, the topics you state are for now further down the list of improvements. I'd like to desmog the bike for the results you mention-am a little concerned emissions may not pass inspection-not sure desmogging will have an effect. First on the list to install a fuel line quick disconnect with dual shutoffs to make tank removal easier (less messy). Then do the ground fix, and for access to the pair valve & coolant fill. Lots to do. Just not all at once. Thanks!

The factory recommended intervals for valve adjustments is every 8,000 mi. In order to adjust valves, all that smog crap has to be removed anyway. Why put it back on, unless your state law requires it? As an older bike, check your state laws to see if it can be deleted. AFAIK, the only state with issues is Californistan, and they have added O2 sensors the other 49 states don't have.