In over my head...Help!

[ndbueller]

Hey Guys I'm in over my head...

I'm pretty new to bikes and Buell. I don't log in much but I've spent some ass hours in front of a computer on the forum trying to learn about my new toy. The only motorcycle work I've done is an oil change. My very first bike is an 07 xb12s with around 17000mi I bought from a buddy a year and a half ago. Its mostly stock except for the engine breather reroute(Big thanks to the guys posting on here for that one). Last fall I took it on a 170 mile ride and when I got there I heard a noise and a front exhaust stud had snapped off flush. Not sure what to do I took it to a buddies shop and we drilled it attempted an EZ out and broke that off inside as well (FML). Having to work the next day I tucked my tail between my legs, tightened up the other side, limped it the 170 mi home, and parked it.

A week ago a neighbor gave me use of his shop to work on it. I took it for a test drive first (couldn't help myself) brought it back to the shop and heard a broken stud from the rear head....Yay! With full use of an old auto shop, many hours researching this forum, and enough farming experience to figure out lefty loosey righty tighty...I decided to tear into it. After I removed plastics I found the culprit. The front Exhaust mount on the bottom of the engine was completely missing. I figure the weight of the pipe plus all of the extra vibration was causing the studs to snap.

Engine rotate then removed frame and front fork completely so I could put the engine/rear swing arm up on a table for better access. It scared the **** out of me but after doing about a Junior College degrees worth of research on the subject I decided that my baby was going to have to go through some surgery to removed the 2 broken studs and EZ out. Welded a washer then nut combo to the studs and wiggled back and forth applying lots of lube until they broke off then repeated for about 5 hours while simultaneously drinking beer for moral lubrication and watching the hockey game (Yes this guys got a dish hooked up in his shop!). They both finally came out clean!!! I was so happy I think I cried a little...then I drank one metric **** ton of beer to celebrate!

While it was apart I got new Spark Plugs in it from ASB(the originals were still in it), drove an hour and a half to HD dealer for new studs/nuts, and did an oil change. Put everything except for the plastics back on last night and took it for a test drive about 11:30(again to excited to let it sit). Here's where my new problem starts. If I hit the gas to hard it kills it. It took me 4 tries to get it to 65 MPH because if I hit 3000 RPM it dies until I hold the clutch in down shift and baby it back into gear. When I got it back into the shop I revved it up in Neutral...same issue, it just seems to bog down like its flooding. I unhooked the airbox cover and looked in the throttle body and it revved up no problem...it ran like a top this way. so put the cover back down and it bogged again. While it was running I put pressure down on the air box cover and it killed the engine completely. At this point I'm assuming that its not getting any air.

Now after suffering through that god awful sob story my questions are....


1) Can an air filter go to hell sitting in a clean shop for a week?(I don't no if it has ever been replaced) Could it possibly be that simple?

2) Is the lack of air just a symptom of a different bigger problem and removing the filter just treated the symptom not the main cause?

3) Do I need to track down a cable and plug it in to a computer? If it's electrical I may be at a loss but it won't stop me from trying

4) Is it possible that I just put Humpty Dumpty back together wrong? I didn't think so because it fired up right away and idled fine but I have no idea what I'm doing so it's definitely plausible.


Any responses are greatly appreciated!! Just remember you're talking to a guy with one successful oil change worth of motorcycle mechanicry under his belt so dumb it down a bit.

Thanks!

 

[Chicknstripn]

Man give yourself more credit!
Awesome job fixing the exhaust stud. That job was not for the faint of heart!
First: Make sure you're NOT revving a cold engine. XBs don't like that and you'll find you're just fouling your plugs and making things worse.
Second: is the throttle body snorkel positioned correctly? Anything obstructing it? The way the airbox is designed you shouldn't be able to choke off the air to the engine by putting pressure on it. Check that the air box base(not the airbox cover) has the factory spacers on the bottom of it and that there is clearance between the airbox lid(part that covers the filter) and the air box cover(the colored plastic piece that usually has a few Buell logos on it.
Also insure your your throttle is adjusted properly.
That's all I can think of.
I'm sure other will chime in with other possibilities.
Good luck!

 

[williegoat]

Just a stab in the dark, but maybe the airbox assembly is interfering with some wiring. The intake air temp sensor, the throttle position sensor and the injector wiring all all up there. Perhaps a loose connection or something is almost pinched and when you install/remove the cover or place pressure on it, something moves just enough. Maybe even the intake seals are moving. Retrace your work on the top.

 

[Marcus_asparagus]

Hmmm, sounds like maybe the air horn trumpet thing isn't sitting down flush enough on the throttle body and the top of the air box is closing off the air passage way?

Just a thought as it can be a bit of a battle to fully seat it down there, no gap should exist when you run your finger down towards the throttle flap.

Good luck, you've come quite far.

 

[ndbueller]

Chicknstripn: Yes, I was pressing down on the "air box base" not the air box cover. I left the cover off for a test ride.

I'll definitely double check everything on top there.

I think you guys may have found my cause with the throttle body snorkle/air horn trumpet thingy. I'm not going to be able to check it until tonight but if that rubber was seated too high on the throttle body it would press up against the air box base cutting off all air flow. (especially when pressed on)


I really hope it's that simple. You guys are awesome! I'll probably be sneaking out of work early to try out your theories...

Thanks guys!

 

[Chicknstripn]

NO! Ndbueller you're awesome because you're working on your own bike!
That what separates the posers and squids from the real enthusiast.


Well, that and a bigger bank account!

 

[AZmidget91]

I would check for an intake seal leak, just to be sure. Start the engine and spray brake cleaner towards the throttle body from the bottom. Aim for where the throttle body meets the head.

 

[ToneTheMoan]

ndbueller "in over my head-help!" mate are you kidding me you aint even in up to your knees! You so underestimate your ability, man if thats your 1st or 2nd job on the bike what the hell will you do for an encore! i am seriously impressed well done and keep going!! :up: :up:

 

[wickedchop]

I'm pretty impressed man, I'm probably one of the worst wrenches on here, yeah I can do my own oil and primary changes, brakes, caliper rebuilds, cables, wheels on and off bearings out etc. Broken stud would've sent me straight for the sledgehammer and the bike might have paid the price! Job VERY WELL done, way to go man. I hope it's an easy fix like these veterans on here are trying to troubleshoot for you. Let us know how ya make out. Again.....WAY TO GO!

 

[Cooter]

I'll also chime in with an Attaboy! That's a PITA job, looks like you did well:up:

I'm not sure if it was explained well enough, but theres a lip on the throttle body rubber that goes OVER the air box base plate. A small dull flathead screw driver with some WD-40 on it, makes the job easy.

Let us know if that was it, and you have to post pic's. It's the rules

 

[user_deleted]

The front Exhaust mount on the bottom of the engine was completely missing. I figure the weight of the pipe plus all of the extra vibration was causing the studs to snap.

the front exhaust mount is attached to a dedicated mounting ear cast into the engine case assembly via a very long 3/16th inch bolt and captive locking nut. during the life of your bike some ham-fisted type clueless in the art of buells either snapped it or cracked it. it then worked itself loose, fell out and took the bracket and front weight of the muffler with it. hence your broken header attachment studs. rear muffler mount entirely different and held in place by 2 large bolts threaded into the motor case.

can the air filter go bad just sitting on the work bench?

no. it was at the end of its service life before it hit the bench.



3) Do I need to track down a cable and plug it in to a computer? If it's electrical I may be at a loss but it won't stop me from trying

cable and diagnostics program (like ecmspy ie.) only necessary if your check engine light (CEL) is activated.....you want to run diagnostics....you want to clear CEL codes....you want to re-map the ecm....you want to reset your TPS sensor.

in all probability your reassembly is incorrect. double check your intake-side work as follows:
1-the large rubber air intake horn affixes to the top of the throttle body with a very large spring clamp and ties the throttle body together with the air system base plate. it absolutely must be installed correctly. installed correctly means the bottom of it is fully seated against the top of the throtttle body. you can feel it fully seating if done correctly. the large spring clamp MUST be installed.
2-the upper lip of the air intake horn is what attaches to the air intake base plate....not the entire top part of the air intake horn....just the upper lip.
3-base plate attaches to frame via 4 identical torx screws. they are exactly the same screws used to attach front fender to fork legs but are 1/8th inch longer. IAT SENSOR affixed to base plate at 4 o'clock position and plugs into harness. it must be plugged in. air filter sits in base plate....air box lid affixes to base plate and corresponding gasket with captive plastic snaps. air box cover goes atop all this. that's the correct order and procedure. nothing else will work.

lastly......here's the simplest trouble-shooting procedure to narrow down what and where the problem might be: assuming here that your CEL is not activated run the motor if possible until same symptom occurs again. shut it off and remove the front spark plug which is by far the simplest. does it appear black and sooty with carbon? if so you have an air-flow problem. is the white porcelain that surrounds the center electrode bright white and pristine appearing? you have a fuel delivery problem.

 

[ndbueller]

Hey guys! Thanks for the help. It was the rubber throttle body horn.

Here's the bike torn apart.



All of the attempts


Successful removal!

 

[ndbueller]

Used a little WD40 while the oil dripped.

 

[ndbueller]

All shined up and fixed thanks to you guys!

 

[ndbueller]

I would like to give a huge shout out to you guys for the support! You replied and solved my issue by the end of the day...I would have never thought about checking that piece of rubber. Ran like a top when put on correctly...here I figured it was going to be something really serious.

Now all I need is a front tire and I'm ready for a 4000 mi moto camping trip from NE North Dakota to San Diego in the end of June!

 

[Cooter]

Well, it was you that did a fine job.:up:

Sounds like a kick ass trip, I should be riding from Los Angeles to Pikes Peak about the same time! I WISH I could ride my CR that long per day, so I'll find a Lightning to use...

 

[ToneTheMoan]

Well done mate! and that is all useful knowledge gained by doing that which will stand you in good stead for your road trip! ENJOY!! Nice bike by the way! :eagerness:

 

[ndbueller]

That sounds like fun! I'm still debating weather I should stay south or take the coastal highway north to WA and head East from there. This will be a first trip but I figure go big or go home.

Do you have any experience riding in either of those areas that time of year? I would have around 8 days to get home so time is on my side but idk if the northern route will still be cold that time of year.