Gen2 copart special: redemption

amirpc said:
I got it bled on stands and it felt great, then I take it off stands and start rolling it and the brakes suck again. Sometimes literally zero braking pressure.

I also hear a lot of scraping from front brakes.

Back on stands and I started noticing some things:

1. The front tire has a huge chunk taken out of it, so it hit something

View attachment 1634580


2. I took off right side caliper and noticed the tire really won't spin freely - you can hear it scraping. On the left side it literally gets stuck ass you rotate the wheel.


3. I took off both calipers and you can actually see the side to side play on the rotors:


4. Now with the calipers off, I get a really stiff brake lever every single time.

So I think the system is bled. I think now its warped rotors...maybe more? Thoughts?
Click to expand...
I'd say you have one or more bent rotors...

I had this happen on one of my bikes and it was a pain to diagnose...I did the same thing as you bled the system again and again, tied the lever back and all...it never even came to my mind the rotor was bent...I took them off finally and placed them on a level surface and one of them was bent pretty good.

Got a new one, and voila, I had brakes again...
 
Front ends can be odd. A trick I learned is loosen all the front end bolts. Where the folks bolt to the tripple trees also. Then spin the wheel as fast as you can and grab the front brake as hard as you can. Repeat several times and tighten it back down. Might not fix any of these issues.
 
Pulled the front wheel off, looked at rotors. Can't tell when off bike if they are warped, afraid it could be something else - such as wheel damage or axle damage. They look perfectly flat when I have them off bike.

So I'm planning on diagnosing from the ground up.

I ordered a $60 dial indicator from Amazon that'll be here tomorrow.

1619038643548.png




1. Test the axle for straightness

I just put a straight edge up against it, looks good. I was thinking maybe strapping dial indicator to something straight and rotating the axle there? Open to suggestions

Book says find a piece of plate glass to roll it on...i don't have any plate glass laying around.

2. Full inspection of wheel for cracks, flat spots & dents

3. Test the wheel for out of round & side to side runout

Gonna try to do this:

IMG_0692.jpeg



I'm just hoping all of those things come back okay and I can assume it is "just" the rotors.

If those things are all good - is it a safe assumption that I should just order new rotors?
 
WuzzaCBXRider said:
You can place the rotors against a pane of glass to see if they’re warped. As you hold them against a window have someone try to slip a piece of paper between them and the glass.
Click to expand...
Awesome I'll try that tomorrow

Is it okay to leave calipers closed like this for a few days or do I need to figure out how to open them up?

6AEE8C61-123B-40B4-99D3-F4324F2BD312.jpeg
 
amirpc said:
Awesome I'll try that tomorrow

Is it okay to leave calipers closed like this for a few days or do I need to figure out how to open them up?

View attachment 1634600
Click to expand...

I’ve never seen the pads so close together but I can’t see how it would hurt anything. You might remove the pads and try tapping a wedge or dowel of some kind in between to expand the pistons. Those look like you squeezed the lever after installing the pads. They have to be spread at least the width of both brake pads so they’ll fit over the rotors.
 
WuzzaCBXRider said:
I’ve never seen the pads so close together but I can’t see how it would hurt anything. You might remove the pads and try tapping a wedge or dowel of some kind in between to expand the pistons. Those look like you squeezed the lever after installing the pads. They have to be spread at least the width of both brake pads so they’ll fit over the rotors.
Click to expand...
That is what I did. After like a day of bleeding I just wanted to confirm that the bleed wasn't the problem.

Okay I'll give that a shot, thank you
 
rebolt up your front axle on the forks as per manual if its done wrong it will bind the brakes.
do it a couple of times to be sure you know why its important not to overlook this operation, important not to underestimate this task as it looks easy but easily stuffed up
 
macka said:
rebolt up your front axle on the forks as per manual if its done wrong it will bind the brakes.
do it a couple of times to be sure you know why its important not to overlook this operation, important not to underestimate this task as it looks easy but easily stuffed up
Click to expand...

will be careful here, thanks!

Finally got to looking at shifter and it is definitely bent to heck, got a new one on the way from eBay.

83286790-9ED7-42D5-856D-5BB68EF779B0.jpeg

110342ED-1698-4A9E-817C-BCF9497DEB04.jpeg


Got the stock undertail on and passenger footrest pillions totally came through! Was very worried about that undertail, but it's in good shape.

48C008E5-CB1B-4DB9-B77F-335AF59DBB35.jpeg


C3CF437C-BF18-465E-B87D-D28052CD31AE.jpeg
 
Threw the stock exhaust on last night just to quiet it down some, gonna get slip ons after it's together.

3066C2AE-7E6D-44D9-8E83-896681F9FDEA.jpeg


I took the wheel and axle to a local shop I like, I needed the new tire put on so I figured I'll have them check out the wheel/axle for trueness and put on some new rotors at the same time. Backing away from doing everything myself on that piece, was intimidated.

I'll align it all and be careful putting together the front end/axle assembly.
 
I'm getting a high idle, like close to 2k.

8DA4B3AD-7208-4303-902C-D9071B04FCFA.jpeg


I thought maybe it was the evap system with a vacuum leak so I plugged it up and it maybe came down a bit but is still maybe 1800.

Im wondering if it could be the flashed ECU - it was set up for drag racing. Any other ideas of where to look
 
Bumblebee said:
Check your throttle cables to make sure one isn't binding slightly or kinked anywhere. Also check the rubber hand grip to make sure it isn't contacting the switch block...

And you can adjust the idle.

A flashed ECU won't make it idle high.
Click to expand...

Thanks for the info!

I checked the throttle cables and no binding
I backed out the idle adjustment screw all the way

1F99FFE1-A434-45EB-8671-3024A39BAA01.jpeg


literally plugged the vacuum line going to evap cylinder

D5BE9443-CE0A-40F9-9F3D-B6217EBD89F6.jpeg


Here's what it's doing, it's like it is adjusting the idle up. After I rev it, it dips down then adjusts back up too.


I had ONE start where it idled at 1300 RPM. I was plugging the hole in back of the evap cylinder with my finger at the time, I couldn't reproduce it. That is when I plugged up the evap tube, never got a normal idle again.

I have ruled out:
  • Binding throttle cables
  • Idle adjustment (backed it all the way out)
  • Vacuum leak from the evap cylinder
The fact that it seems like the ECU is adjusting up the idle makes me think its vacuum.

Questions:
  • The gas in the tank is old, it is the original gas I got with the bike - and it has been sitting since October. Could that cause something like this?
  • Where all should I be looking for vacuum leaks? I looked over the lines from the throttle bodies to the evap cylinder purge valve, seems fine. I took the evap cylinder out of the equation. Where else?
 
amirpc said:
Thanks for the info!

I checked the throttle cables and no binding
I backed out the idle adjustment screw all the way

View attachment 1634883

literally plugged the vacuum line going to evap cylinder

View attachment 1634884

Here's what it's doing, it's like it is adjusting the idle up. After I rev it, it dips down then adjusts back up too.


I had ONE start where it idled at 1300 RPM. I was plugging the hole in back of the evap cylinder with my finger at the time, I couldn't reproduce it. That is when I plugged up the evap tube, never got a normal idle again.

I have ruled out:
  • Binding throttle cables
  • Idle adjustment (backed it all the way out)
  • Vacuum leak from the evap cylinder
The fact that it seems like the ECU is adjusting up the idle makes me think its vacuum.

Questions:
  • The gas in the tank is old, it is the original gas I got with the bike - and it has been sitting since October. Could that cause something like this?
  • Where all should I be looking for vacuum leaks? I looked over the lines from the throttle bodies to the evap cylinder purge valve, seems fine. I took the evap cylinder out of the equation. Where else?
Click to expand...
I don't believe it's the fuel however I'm not 100 percent but I think there maybe an idle adjustment in the ecu but the bike that i know where they played with that is a turbo bike so I'm not sure if that was the stock ecu or not. Does your ecu have any tags or writing saying what was done when it was flashed??
 
amirpc said:
Thanks for the info!

I checked the throttle cables and no binding
I backed out the idle adjustment screw all the way

View attachment 1634883

literally plugged the vacuum line going to evap cylinder

View attachment 1634884

Here's what it's doing, it's like it is adjusting the idle up. After I rev it, it dips down then adjusts back up too.


I had ONE start where it idled at 1300 RPM. I was plugging the hole in back of the evap cylinder with my finger at the time, I couldn't reproduce it. That is when I plugged up the evap tube, never got a normal idle again.

I have ruled out:
  • Binding throttle cables
  • Idle adjustment (backed it all the way out)
  • Vacuum leak from the evap cylinder
The fact that it seems like the ECU is adjusting up the idle makes me think its vacuum.

Questions:
  • The gas in the tank is old, it is the original gas I got with the bike - and it has been sitting since October. Could that cause something like this?
  • Where all should I be looking for vacuum leaks? I looked over the lines from the throttle bodies to the evap cylinder purge valve, seems fine. I took the evap cylinder out of the equation. Where else?
Click to expand...
That's a bit of a stumper....I've never heard of an ECU being flashed and adding a higher idle rate-having a higher idle would do little for launching at a drag strip...

It's got to have a vacuum leak-there are tests for that at least...
 
Sounds like it’s sucking air to me. I would personally pull each vacuum tube off the throttle bodies and plug the tb and test. Another way to test for vacuum leak is with either ( yes I’m old and did this with Jesus’s cars ) lol There may be a better way nowadays but it’s quick and effective. Spray the possible area. If it revs up, there’s a leak
 
Spoke to the guy who flashed it, he said the flash

- raised the limits
- disabled abs
- turns fan on 10 deg sooner
- turns on upper fuel injectors 2k rpm sooner

His suggestion is to check out the vacuum lines around the air box especially the MAP sensor.

Today I'll go poking for vacuum leaks
 
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