Hi Guys,

I have just rebuilt the engine on a bike which my son stripped down a couple of years ago.
It is now together enough to start. I have decent compression, oil pressure and sparks, but the injectors are not, erm, injecting.
The neutral switch is broken, so according to the neutral light, it is in gear.
My question is that if the clutch is in, but the bike is in gear, would that cut the fuel inection syatem?
I'm hoping so, as that would explain it not starting.

Thanks in advance.

It should but make sure the plunger switch behind the clutch lever is operating other wise the ICU still thinks the clutch lever is out.

Thanks Rick,

The clutch switch is working. When depressed, it won't turn over at all.
When not depressed, it turns over but I have no fuel from the injectors, although the fuel pump is working.

Go to the Portal page then to the tech page and under Misc you will see a flow chart for the bike not starting.

Awesome, thanks Rick.
I wasn't sure how to test the injectors and the fuel control unit, so that is super helpful.

Hopefully, I will have some good news in a day or two.

Shoei wrote:I have just rebuilt the engine on a bike which my son stripped down a couple of years ago.

While you've been at it, did you replace the fuel filter and fuel lines in the tank, then check that fuel was being delivered under pressure at the fuel rail?

I haven't had the pump out of the tank yet.
I'm just trying to get it running before I rip it apart again to start the rebuild.
I haven't checked the actual pressure as yet, but it's coming through pretty quickly.

"will a k100 start in gear with the clutch in"

It should since power to the start button then bypasses the gear switch by a circuit through the clutch switch to the start button.

If the injectors aren't making a ticking sound, you might have an electrical problem.

You need to tell us engine type. 4v engine has a side stand cut out.

92KK 84WW Olaf wrote:You need to tell us engine type. 

His profile indicates it's a caffeinated K100LT so that eliminates 4V.

Laitch wrote:

92KK 84WW Olaf wrote:You need to tell us engine type. 

His profile indicates it's a caffeinated K100LT so that eliminates 4V.

I did not look in there......

But...cafed could mean the clutch switch cable is accidentally incorrectly connected to the loom as front or rear brake or choke cable or clutch connectors are identical as they are the same switches.

Thanks guys,

Yes, it is an 8 valve 87 LT, which made lapping the valves considerably quicker than what I'm used to.  

I have checked the injectors and 2 are firing and 2 are not. They have all had a session in an ultrasonic bath, so I assume the 2 that are not working are f****d?
The fuel pump is working, but I'm not sure if I have enough pressure from it, so will be ordering a fuel pressure test gauge.
If I have low fuel pressure, is that likely to be down to fuel pump or could it be the pressure valve thingy on top of the throttle bodies?

Sorry for all the questions, but I am more accustomed to analogue fuel injection (carbs).

Shoei wrote:Thanks guys,

Yes, it is an 8 valve 87 LT, which made lapping the valves considerably quicker than what I'm used to.  

I have checked the injectors and 2 are firing and 2 are not. They have all had a session in an ultrasonic bath, so I assume the 2 that are not working are f****d?
The fuel pump is working, but I'm not sure if I have enough pressure from it, so will be ordering a fuel pressure test gauge.
If I have low fuel pressure, is that likely to be down to fuel pump or could it be the pressure valve thingy on top of the throttle bodies?

Sorry for all the questions, but I am more accustomed to analogue fuel injection (carbs).

Important first to check the cylinders of the injectors not firing. If you did the test on bench etc your diagnosis is likely correct. If you did it in the bike trying to run it and its showing up and 1 and 4 or 2 and 3 then your problem is very likely to be elsewhere and electrical. If this is the case maybe a Hall Effect Sensor [HES] related issue or the connectors on that line.

I tested them on the bench, then on the bike to make sure.
2 are definitely faulty, so I have ordered a new set. Just need to check the fuel pressure now.