Help! Throttle body swap that ended bad.

Hello, first time poster, owner of a 2009 bandit 1250 ABS

I was starting to do all of the dale walker mods, by removing the secondary throttle boddies.

I got 2 sets out(#3, #4 cylinder) , and drilled out the other 2(#1,#2). There was just a tiny amount of metal shavings i wasn't able to get out of one of the butterfly valves(#1).

Anyways, I put everything back in, clamped it down and started the bike.

Bike was extremely rough and had a hanging idle when I rev'd it.

I found out I missed a few clamps on the airbox, tightened down and started the bike back up. very rough idle, and constant white smoke, like steam with liquid just spraying out of the back of the exhaust. Oddly enough, the liquid didn't have a smell to it, could've been water. One of the headers was barely warm while the others were piping hot. I replaced all the spark plugs and wires. For some reason, the #4 cylinder isn't firing.

Now this bike has been perfect up until this point, I really don't believe a head gasket magically broke on startup from just removing a throttle body and putting it back on.

Now for the odd part is, if I disconnect the number #4 cylinder. The bike stops pushing out white smoke and runs normal, except for the the fact its running on 3 cylinders. If I disconnect any other cylinder, the bike stops pushing out white smoke and runs normal. As long as its running on 3 random cylinders there is no smoke, or steam or whatever.

I've noticed on the top of the throttle body, there is one oddball hose that I can't seem to find where to connect it to, reference (part#7)http://www.bikebandit.com/oem-parts/2008-suzuki-bandit-1250s-gsf1250s/o/m147552#sch554495

I've rechecked everything a thousand times over and can't figure this out.. already ordered another set of throttle bodies that should come in monday, but this is driving me crazy - Any idea where to look?

Maybe MetricMetal here has an answer. Or get a service manual and look at pictures.

PS: You LEFT some metal shavings inside throttle body?????????????

There was a massive vacuum Leak, I didn't seat the throttle bodies all the way into the intake manifolds. However, now that I did, all cylinders firing. No white smoke. Now lots of black smoke, tons of fuel smell in the air, the bike runs as long as i keep the throttle open (sort of like a choke in a way) but as soon as i let off the throttle the bike immediately dies. Tons of fuel smoke in the air and out the exhaust. No vacuum leaks, tests all around with carb spray, just can't get the bike to stay running whatsoever. and P.S. tiny, tiny amounts of metal shavings that just were not possible to get out. They were brass from the throttle bodies. Many mechanics at my work say small metal shavings getting into the engine won't do a darn thing but work its way out. They say engines won't get touched by metal shavings unless you dump tons of it in there.)

Ridiculous. Why bother with air filters in that case? Some of the metal particles will go out the exhaust, and some will wind up between the piston and the cylinder wall. A tiny amount of brass will not likely cause any noticeable harm, but why risk it?

I watch the market for interesting used bikes. Any owner mods make me suspicious, and in many instances make the bike less desirable than a stock machine. It's not always the case, but I generally view farkling as a way to spend money to make a motorcycle less valuable.

^^^^ +1

Okay in the spirit of helping.... Your pumping out black smoke and smell raw fuel which says you are running very rich. You could pull the plugs to confirm that they are black and wet if you want.

I'm not familiar with this particular swap, but to start down the path of logical troubleshooting...

Are all wiring connectors plugged together?
Are the needed sensors in place and connected electrically? (TPS, O2, CPS, HE, etc.)
Do you have all of the hoses connected?
Have you changed anything else besides the throttle bodies?
Have you changed the fuel mapping in the ECM? Do you need to?

A quick search yielded the need to drill the air box and use a K&N filter for it to breath properly. Has this been done?

I'd encourage you to reach out to the parts manufacturer (Dale Walker - Holeshot Performance) and see if they have some relevant information. The guys that do this mod regularly are going to know a heck of a lot more about it than many here. Good luck with getting it sorted out!!

Dale is a member here, you might try a PM. He hasn't logged in in a while, but he does get notification to PM's and accepts email.

I appreciate the replys. As i was about to give up, i saw a vacuum hose diagram by the taillight. It showed the very original picture in my post of that oddball hose i had no idea where it went. It connectes to the map sensor. Bike completely back to normal, checked cylinders for metal shavings, went on a long ride, came back, compression tested each cylinder at 210 across the board. All is well

some times you just have to vent, or vacuum as the case may be.

reidk15 said:

I appreciate the replys. As i was about to give up, i saw a vacuum hose diagram by the taillight. It showed the very original picture in my post of that oddball hose i had no idea where it went. It connectes to the map sensor. Bike completely back to normal, checked cylinders for metal shavings, went on a long ride, came back, compression tested each cylinder at 210 across the board. All is well

Click to expand...

What method did you use to check the cylinders for metal shavings?

As i did a compression test i scoped all of the pistons, used an air compressor to blow out the throttle bodies and airbox and make sure everything is squeaky clean. Bike has been running great, did an oil change and found no trace of shavings anywhere else.

Glad you got her all cleaned out!