View Full Version : 99 Buell X1 1200cc

08-02-2010, 10:07 AM
I've got a 1999 1200cc Buell X1 Lightning Racing Stripe (not sure if anything besides the paint is special on it).

I am having a problem with intermittent high idle (2k or 2.5k rpm) when I sit there after riding for a bit. I also have a nagging hesitation @ 4k rpm when accelerating but it pulls through after 1/2 seconds. There is a leak that looked like it was coming from the rocker box gasket but a buddy of mine noticed the airbox was loose and thought it might be stuff coming out from the throttle body.

I just replaced a rubber grommet piece that resides between the snorkel and throttle body. I also replaced a hose that was cracked at the end in the airbox that went to the front head. I was hoping this would fix the issue but to no avail it didn't seem to help any.

Any suggestions on what to check next? I know I need to figure out where the leak is coming from and I will try but am a novice to troubleshooting and am learning about bikes as I go here. I was hoping the symptoms might give someone an idea to help me out here.

Thanks for you time!

08-02-2010, 12:52 PM
i have a 99s3, i had some of the same problems. i would replace all the intake and exhaust gaskets, make sure everything is tight and no leaks. use the ecm spy and reset the tps and afv. this helped with my bike, i have had to tune a little bit to get the popping out.
i have eproms for 99x1 stock and my s3 race eprom, i will share if you need. you have to make sure you have no intake or exhaust leaks before you try to do any tuning or tps resets!!!

08-03-2010, 05:41 AM
Take a picture of the plus if you can and let me see them and I should be able to tell if it's lean or rich! Just make sure to get a good shot of the center insulator and down into it. Too me it sounds as if it is running lean or has an air leak causing it to run lean.

08-03-2010, 12:36 PM
I'll try to get a picture up for you of the plugs.

There's one spot I wasn't sure about...where the snorkel hose connects to a rubber piece (it separates the snorkel and air filter). It doesn't seal at all but not sure how snug that should be as the hole for the connection on the rubber grommet is large enough to leave a a decent amount of room around the snorkel hose. I may post a pic of that too. I'll call Harley on this one and see what they say about that connection. Maybe that rubber grommet needs to be tighter somehow over the snorkel hose.

There are 2 holes at the top of the snorkel hose that lets air in the airbox...not sure what that's for but the snorkel was made with them built-in.

08-04-2010, 06:50 AM
I would look into getting the Buell oval air cleaner if your still running the stock bread box.It performes better and is alot less complicated then the stock set up. Mines carbed but they have one for FI bikes.

08-04-2010, 08:41 PM
http://harleybigboreintakes.com/ i have had great service and performance from them, untill you drop your bike like a idiot on that side and smash it!! they are cheaper than other kits, less than $200. nullhttp://www.buellxb.com/buell_images/7050_20100602191704_L.jpg

08-07-2010, 09:30 PM
Here is a picture of the plugs and airbox.





08-08-2010, 09:06 PM
I found at least one leak for sure at the bottom of the rocker box. You can feel air coming out of the side on every stroke. I was told a rocker gasket won't affect performance but is that true? If I do the rocker gaskets, I might as well do the head gaskets, right? It's a 99 and has 20k miles on it. This will be the first I've done it on my own. :)

08-09-2010, 05:26 PM
Forgot to mention...I do have a K&N air filter and Vance & Hines muffler. I wasn't sure if the exhaust might be causing my problems since it's not stock. I bought it with everything that's on it now so I wouldn't know the difference from stock.

I was told Harley places can't change the stock ECM, is that true?

08-10-2010, 09:41 PM
The left one in the picture looks as if it is running a lot leaner until the higher RPMs the one on the right doesn't look too bad but it is still a little lean on the idle and low speed, but for sure there is some reason it is running lean on the left one in the picture.

08-16-2010, 05:47 PM
So I replaced the rocker gaskets and the oil leak has stopped and it actually seems to run better. It had an oil change and I'm running 20W50.

There is still a lurking desire to hesitate on me around 4k rpm but not as bad and a strange high idle issue still. It appears that if I can get it in a gear that makes it shoot under the 2k mark and then clutch it again, it will try to idle @ 1k again but doesn't always work.

I'm wondering if hot weather makes the idle issue worse somehow. Maybe a sensor is heating up or something?

thomas_cronan said to check for air leaks on the intake and exhaust gaskets. What is the best way of doing this? It's sort of a pain to get up underneath with the black boxes on the sides.

I almost forgot...It doesn't always stay started whether I've been driving it a while and stopped for gas or a cold start...doesn't seem to matter. Then sometimes it will idle fine after a start. Hopefully all of this points to only one issue and it will fix them all. I'm thinking about trying C-Foam out but not sure if that will help with any of my symptoms.

Thanks for any further help!

08-16-2010, 08:22 PM
i always used a stethoscope with a open end always worked for me, there is a spray (i think) that will bubble and tell you if theres a leak. another thing what is wrote on your ecm? is it a race, a 2000 upgrade or a 99 that was recalled? i know s3 had bad ones in 99, and most parts are the same for x1? where do you live? check for leaks and reset all your tps and all that. sounds like its in the tuning.

09-01-2010, 11:43 AM
i had the same problems with my x1 when i put the V&H with the K&N with a forcewinder intake. i got a race ECM that took care of it for me. but if you have had all the upgrades and just noticed now it would have to be something else

09-15-2010, 10:36 PM
Thanks for the posts guys! I'm in the St. Louis, MO area. I have the stock air intake.

I don't know what resetting the "TPS" means or what tps even is. Do I need a dealer to do this for me as I have no software to program my bike? I am a computer guy though. [up] Would a TPS reset be needed on a stock ECM after installing a V&H muffler with a K&N air filter? I bought the bike with these already on it, so I'm learning the hick-ups of the bike as I go.

The ECM says "VDO Control Systems, Inc.", so I'm guessing this is stock. How much would an ECM upgrade probably cost me and could I blow up my bike easily with one if I would be starting from scratch learning how to program one?

Here are some letters/numbers I got off the ECM if it helps any at all:

N0306.K 99040
VDO Control Systems Inc.

06-30-2013, 11:56 PM
Once I figured out how to do a TPS reset and buy a cable with ECM spy for my bike, the TPS reset fixed my high rpm issue.

Thanks to those who gave input!