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2007 R6 Won't Idle After Rebuild, Starting a Maintenance Log For the Community

2K views 18 replies 3 participants last post by  Avium 
#1 ·
For some background: Picked up an 07 R6 with a bad rod knock and 40k miles on it. Replaced the crankshaft, rod bearings, connecting rods, piston rings, spark plugs, and all gaskets.

After getting the bike back together and trying to start her, she would only run with the starter held down when below 4k rpm. Bike dies immediately once I let off the throttle and the revs drop below 4k. Won't idle at all.

Starting a maintenance log for anyone who may run into this issue in the future.

For starters, it desperately needs a valve adjustment, but I'm going to attempt to get it to idle before that.

So far I've checked the stator, and it was putting out 13v at ~4krpm which is in spec.
Bike doesn't throw any codes whatsoever, though I've only had it running for a couple of minutes and that was all above 4krpm(never above 6k).

Up next is running dIAGs on the TPS and injectors, checking the ignition coil resistances, inspecting spark plugs for carbon, and checking all of the plugs for a spark via dIAG.

Will update this thread as I move down my maintenance list.
 
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#2 ·
Ran the diagnostic on the TPS and injectors, both were in spec according to the manual.

Ignition coil resistances were all within spec, and the spark plugs all provided a spark that was within spec.

Checked rectifier for any signs of a burnt plug, everything looked good there.

Going to be putting an OEM exhaust on tomorrow(there exhaust on it right now was cut off just behind the cat). Hopefully the OEM exhaust paired with the currently dangling O2 sensor will help it out.

Once the exhaust is on and the bike is a little quieter, I'm going to recheck the stator for a proper 14v at 5k revs.
 
#4 ·
Annnnnd problem found. Pulled valve cover off and almost all of the exhaust valves were too tight to get a shim into. Every single valve on the intake was also way out of spec.

60 dollar shim kit and a six pack later and the bike sounds brand new. Cannot believe .2mm stopped it from even starting up.

Now onto the next problem! When I dropped the engine I may have put a tad too much pressure on the side stand switch, so now when the bike is put into gear it shuts off immediately. New(well newer) one is on the way!
 
#6 ·
......Cannot believe .2mm stopped it from even starting up.....
Think about it this way. If a valve is tight...to the point that you can't get a feeler gauge in....that valve is being held open a bit. So, you are losing compression. That cylinder won't run well at idle because at low engine speeds, the air loss will have a greater effect than at higher speeds.

When the engine comes up to temperature it gets worse because the valve stems actually grow from thermal expansion. That is the reason for the valve clearance in the first place...so the valve stem has space to take up when it grows. If you have no clearance when the engine is cold, surely the valve will be held open when the valve stem grows .1-.2 mm. And there will be less compression.
 
#5 ·
Lift the tank and unplug the side stand switch. Jumper the wires on the harness side (not the side that leads to the side stand). I use a piece of safety wire to connect the tow wires in the plug then tape it up when I prep the bike for track days so I can remove the stand.

Bear in mind that it will start in gear after this, bat at least you can get the bike going while waiting for the new switch. And using my method allows you to plug in the switch because you didn't cut or splice any wires.
 
#9 ·
Annnnd I just replaced the kickstand switch to no avail. Bike still dies immediately when taken out of neutral and put in gear(while holding the clutch in, with the sidestand up). I tried jumping the wires in the old sidestand switch and that didn't work either. Open to ideas at this point >.>
 
#10 ·
So I ran dIAG 20(sidestand switch test) with the new sidestand switch installed, it shows the sidestand as OFF(extended) when the stand is either retracted or extended.

I jumped the two sidestand wires together as per 8Ball's suggestion, and got no change in the dIAG results. This is leading me to believe that the problem lies further down the wiring harness than I expected.

So I did a quick continuity test on the sidestand connector next to the battery, and it read out as 1ohms which I believe(I'm new to this) means my problem is in fact farther down the harness. Now looking at the wiring diagram, I need to check either the Starting Circuit cut-off relay, or the Fuel pump relay.

Gonna dig around in those with a multi-meter and report back.
 
#11 · (Edited)
Alrighty I think I'm going to need a bit of a hand with the wiring diagram.
Imgur: The most awesome images on the Internet

according to that picture I'm looking for a relay that is 10 Wires widthwise by 2 wires height wise? I have no idea where in the world that is on the bike. Manual says 13 should be the "Relay unit" but I have no Idea which one that is.

13.Relay unit
14.Starting circuit cut-off relay
15.Fuel pump relay
16.Neutral switch
17.Sidestand switch
 
#13 ·
After about a weeks worth of hair pulling, I found the POS relay unit. It's in front of the battery right under the gas tank.
http://i.imgur.com/M0naoNx.jpg

Okay, so I tested for continuity and was getting absolutely nothing out of the sidestand connection in the relay unit. I got so mad that I ripped the wire out of the relay plug, stuck my test light in the hole, and tried to groud/complete the circuit that way. Picture for reference: http://i.imgur.com/t8ZnmGF.jpg

Annnnd Absolutely no power going to that wire for some reason. At this point I'm about to say **** it and just ground out my neutral switch permanently and tape over the indicator light. Ruling out that, my only other lead for bad juju is the starting circuit cut off relay, but according to the diagram I posted before, that's INSIDE the relay unit. Which, if it actually is inside the relay, would mean replacing the entire relay. I'm so tired of throwing money at ghosts that the 50 bucks for a part that may or may not fix the problem just isn't worth it.

Also, thanks for consistently chiming in 8ball ^.^
 
#14 ·
Wow, so I may be an idiot. The original owner of the bike had his ignition wires cut and the wires are all reconnected in a pretty jenky manner.

Namely, there are two little blue wires that are twisted/ soldered together, and one black wire just hanging loosely out of the main switch. Turns out, one of the blue wires goes directly to the ecu, and the other straight into the starter circuit cut off relay! Jesus christ this is turning into a massive headache >.<

http://i.imgur.com/8MXvi52.png
3. Is the main switch which leads into #13 which is the main relay(as well as starter circuit cut off relay.) What a mess hahaha.
 
#15 · (Edited)
Shake the relay. Does it rattle? Not really a 100% test.....but usually that relay fails by burning out one of the diodes and sometimes the blown pieces are loose inside it. If it does rattle, it's bad.

BTW, power comes in from the blu/yell wire (well not really power...since it is on the negative side of the ECU circuit). More accurately the current flows from the B/Y wire to the wire you ripped out then goes to ground through the side stand switch.

Try this: Put the wire you ripped out in with the Blue/yellow wire so they are touching. (I see that there are 2 B/Y wires. You need the one that rings out to the clutch switch) See if it will start. If so, the relay is bad
 
#16 ·
No noticeable rattle coming from the relay.

I plugged the sidestand wire directly into the blue/yellow wire, the bike would still not start in gear but turned over just fine in neutral. I tried it with clutch in/kickstand up + clutch out/kickstand down, still didn't start in gear :(
 
#18 ·
I checked the relay via the page you linked and sure enough the kickstand and clutch diodes were shot. New relay is on it's way, I'll update once it's in the bike.

Can't thank you enough for the consistent help 8ball. If you're ever in so Cal drinks are on me.
 
#19 ·
8Ball YOU ARE THE MAN MAN!! New relay installed and took the bike out for the first real test ride to start breaking in all the new parts. Oil light was on for a few minutes but shut off towards the end of the ten minute ride(I know it's good on oil).

NEW PROBLEM THOUGH! In sixth when I pulled the clutch in at about 50 mph the revs dropped to idle and then bam, engine completely shut off at 50mph. It instantly restarts when I let the clutch out though... ARGHHH! more gremlins to chase!
 
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