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XB Throttle Body Question, is this missing a cap or hose?

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Danthehitman

Well-known member
Joined
Feb 18, 2020
Messages
109
Location
Milwaukee and Illinois
Hey everyone,

I was just cleaning the throttle-body to get my TPS to properly hit 0 degrees (which I'm happy to report was achieved!) and noticed this vacuum line connector. Is this ok or should it have a cap, or hose, connected?

Thanks for your feedback,

Dan
 

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No. That port is blocked. No need to plug it.

please stop posting INCORRECT INFORMATION on this board.

it is the california emissions canister vacuum port. if your XB is NOT equipped with CA emissions canister....THEN PLUG IT with suitable 8mm rubber vacuum plug. leaving it open not only ingests unfiltered air but creates erratic idle and often times "hanging throttle" condition. if you don't have one any local auto parts store will. do not use piece of hose with bolt or screw jammed in end.

throttlebody.jpg
 
OP, make sure you get that air horn installed correctly or you will also have idling issues.
 
please stop posting INCORRECT INFORMATION on this board.

it is the california emissions canister vacuum port. if your XB is NOT equipped with CA emissions canister....THEN PLUG IT with suitable 8mm rubber vacuum plug. leaving it open not only ingests unfiltered air but creates erratic idle and often times "hanging throttle" condition. if you don't have one any local auto parts store will. do not use piece of hose with bolt or screw jammed in end.

View attachment 13371

Sorry Cooter, I'm with mr. grumpy pants on this one.

This reminds me of the Austin Powers scene of "Shhhh!"... if I only knew how to make him say "you're wrong!" that would be hil-a-rious.

However, I think Dean mentioned somewhere that plugging the port changed how the bike ran. Personally I dont know why that would be the case, as its ahead of the butterfly... but it seems like loose/missing stacks create issues too (like outthere mentioned), so there is that.
 
Thank you for the additional posts, fellas. I will plug that port up to be safe. This is a Wisconsin issued title so no California emissions.

Outthere, as for the "air horn", are you talking about the rubber mushroom-shaped component that sits on-top of the throttle body (two allen-screws, front/back)? If so, I was a little curious as to how snug that's supposed to be. It would seem the position of that bracket that holds it down would be the critical component to align it properly. I think mine is slightly bent but I could bend it a bit to hold that down harder if that's critical?

Thanks again!
 
LF, you have spewed that wrong info before, and I baited you to posting it here. So check yo self foo! lol.
Honestly, Cliff Claven-Fringe could be right, but trying waaaay too hard:sleeping:
OP: I wrote a concise answer that applies to you. Don't worry about him adding confusion here, LF is over-achieving for my sake, not yours. I'm his catnip:cool:

You can put a plug on there if it makes you feel better, it won't hurt anything. Neither will leaving it alone. So, if anyone still cares...

please stop posting INCORRECT INFORMATION on this board.
I posted concise information that applies to the question and is correct.
Your response to him, is wrong.
it is the california emissions canister vacuum port. if your XB is NOT equipped with CA emissions canister....THEN PLUG IT with suitable 8mm rubber vacuum plug.
It is the port for that, but it is not open to vacuum.
leaving it open not only ingests unfiltered air
Absolutely false. It is not missing a plug, you would know right away for the reasons listed below. The factory never installed one there, because it is not open to vacuum on your bike Dan.
but creates erratic idle
NO. Even if it was a California bike... with a missing canister... and missing plug... It is still PORT vacuum and insignificantly exposed to vacuum when at idle. That is the purpose of a "port vacuum" signal. The port would only be open off-idle.
and often times "hanging throttle" condition.
Still NO. Once again, even if port vacuum is left open, when you close the throttle, that "ported vacuum", is effectively closed to vacuum and therefore unable to affect idle.
That is a picture of a factory stock TB, without any plug on that nipple. Thank you for proving my point in your own post:)

All Buell XB throttle bodies do have that nipple. BUT, it is wrong to assume (and post as 'fact') that it is open to vacuum. Only the XB's destined for California and some off-shore, had the port machined through into the throttle body, and the appropriate compliant Evap emissions system installed.

Thats why theres no plug on yours now. Because the factory did not put one on it.

People commonly (but wrongly) think that is a port vacuum leak because, they assume incorrectly that any open fitting, is open to the throttle body.

Yours is not Dan, because ALL of the conditions below would have to be met, and you still would have BIG clues I would have addressed in my original, and concise post to you.

IF your bike was originally a California (or some off-shore) bike (it isn't) and,
IF someone removed that canister, and
IF they removed the port vacuum line at the TB, and
IF that person didn't plug that port when they took the line off,

Then you'd have a leak. Duh. And it would not be a "minor" leak. An open 5/16" hole is a TON of airflow. So, your bike would stutter off idle, run massively lean, run hot, and you'd have a big CEL in your face. Since you didn't mention any of those issues in your original post, your bike has a extremely high probability of not having the hole behind that nipple in the TB machined open and therefor NO leak there at any throttle opening.

Just like the VAST majority of Buells.
Thats why I didn't confuse the question, explaining that uber-rare circumstance,
thats why the factory doesn't put a failure prone plug on that nipple,
and that's why you didn't mention any running issue,
and thats why you don't need a plug on yours.

Wanna be 100% sure? Start it, crack the throttle, and put your finger over it. I'd put 1000 crispy internet points that it does not pull vacuum. If I'm wrong? Well hey, put a plug on it and I'll take my lashings.

To outtheres point: Yes. Be very sure the bottom of the TB airhorn gasket sandwiches the lower airbox plate. XB's are very sensitive to any intake leaks. Further proving my point.

TL;DR Sorry everyone, for the wall o' text. I wouldn't normally GAS but that guys gone all cray-cray over me. I can hear Cliff Claven-Fringe slamming keys frantically researching other off-topic exceptions, hovering over the 'ALL CAPS' button. This is fun!
 
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LF, you have spewed that wrong info before, and I baited you to posting it here. Time for you to check yo self foo!
LOL. Honestly, Cliff Claven-Fringe could be right, but trying waaaay too hard:sleeping:
OP: I wrote a concise answer that applies to you. Don't worry about him adding confusion here, LF is over-achieving for my sake, not yours. I'm his catnip:cool:

You can put a plug on there if it makes you feel better, it won't hurt anything. Neither will leaving it alone. So, if anyone still cares...


Blah, blah. I am posting concise information that applies to the question. You are posting mis-information that does not apply to the question asked. OH, and is wrong.

It is the port for that, but it is not open to vacuum.

Absolutely false. It is not missing a plug, you would know right away for the reasons listed below. The factory never installed one there, because it is not open to vacuum on your bike Dan.

NO. Even if it was a California bike... with a missing canister... and missing plug... It is still PORT vacuum and insignificantly exposed to vacuum when at idle. That is the purpose of a "port vacuum" signal. The port would only be open off-idle.

Still NO. Once again, even if port vacuum is left open, when you close the throttle, that "ported vacuum", is effectively closed to vacuum and therefore unable to affect idle.

That is a picture of a factory stock TB, without any plug on that nipple. Thank you for proving my point in your own post:)

All Buell XB throttle bodies do have that nipple. BUT, it is wrong to assume (and post as 'fact') that it is open to vacuum. Only the XB's destined for California and some off-shore, had the port machined through into the throttle body, and the appropriate compliant Evap emissions system installed.

Thats why theres no plug on yours now. Because the factory did not put one on it.

People commonly (but wrongly) think that is a port vacuum leak because, they assume incorrectly that any open fitting, is open to the throttle body.

Yours is not Dan, because ALL of the conditions below would have to be met, and you still would have BIG clues I would have addressed in my original, and concise post to you.

IF your bike was originally a California (or some off-shore) bike (it isn't) and,
IF someone removed that canister, and
IF they removed the port vacuum line at the TB, and
IF that person didn't plug that port when they took the line off,

Then you'd have a leak. Duh. And it would not be a "minor" leak. An open 5/16" hole is a TON of airflow. So, your bike would stutter off idle, run massively lean, run hot, and you'd have a big CEL in your face. Since you didn't mention any of those issues in your original post, your bike has a extremely high probability of not having the hole behind that nipple in the TB machined open and therefor NO leak there at any throttle opening.

Just like the VAST majority of Buells.
Thats why I didn't confuse the question, explaining that uber-rare circumstance,
thats why the factory doesn't put a failure prone plug on that nipple,
and that's why you didn't mention any running issue,
and thats why you don't need a plug on yours.

Wanna be 100% sure? Start it, crack the throttle, and put your finger over it. I'd put 1000 crispy internet points that it does not pull vacuum. If I'm wrong? Well hey, put a plug on it and I'll take my lashings.

To outtheres point: Yes. Be very sure the bottom of the TB airhorn gasket sandwiches the lower airbox plate. XB's are very sensitive to any intake leaks. Further proving my point.

TL;DR Sorry everyone, for the wall o' text. I wouldn't normally GAS but that guys gone all cray-cray over me. I can hear Cliff Claven-Fringe slamming keys frantically researching other off-topic exceptions, hovering over the 'ALL CAPS' button. This is fun!

Absolutely false. It is not missing a plug, you would know right away for the reasons listed below. The factory never installed one there, because it is not open to vacuum on your bike Dan.

wrong again Einstein....but nice try.



you sure do come unglued when you're wrong....which sadly for unsuspecting board members...is occurring with way too much frequency.
here ya go idiot: just removed a brand new one from the factory box to disprove yet more of your ridiculous bull****.


xbtb.jpg
 
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LF. You just deleted posts I made referencing pulp fiction where I Clearly censored the cuss words. Your reasoning was it makes us look bad. You need to delete this post. You just lost all my respect man. Shame on you. You can do it but I can’t? Come on
 
LF. You just deleted posts I made referencing pulp fiction where I Clearly censored the cuss words. Your reasoning was it makes us look bad. You need to delete this post. You just lost all my respect man. Shame on you. You can do it but I can’t? Come on



site owner Paul deleted them.
 
Sorry Cliff-a-tic. You are still wrong.

Even if you can blow all your hot air through that fitting, it only proves that TB to be able to be used on a Cali bike. Whats that smell? LOL
 
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I hereby APOLOGIZE to you Dan, and the poor suckers who read this whole pathetic thread:( I am embarrassed for the way I reacted to a false accusation from one stubborn know-it-all. This thread is the exact Facebook style pointless crap-show that us helpful, polite, members here on BuellXB, want to avoid.

This thread needs the first 2 posts only, and even though my info is 100% correct, I will clean this up and delete my responses (again) as soon as Mr. Claven-fringe predictably deletes his. Again.

Sorry guys.
 
Hey guys, I feel terrible for inciting a riot with my vacuum port question! I must say, I do appreciate the passion you all have for this topic...and working for 5 years just 5 feet from EB's office, I know he'd appreciate your passion ;) Buell blood runs hot!!!
 
OP, there's lips on velocity stack. The cover is sandwiched in between them. First go round getting it installed correct is the hardest. second time a breeze.
 
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