2013 Txc310r Won't E-start Or Kick (yes, I've Searched... A Lot)

Hi all, I'm at my wits end here, hoping for some help. I bought the bike "new" as a demo in 2013, and the e-start was never great, but worked most of the time if I was patient. Last couple rides it hasn't worked at all, and now the bike won't even kick start. Here's what I've tried/checked/replaced:

E start button replaced; helped for a while.
New battery; made no difference.
Pulled apart starter (smelled burnt), cleaned it out, replaced brushes; spins when not installed but still no starting.
Checked valves, all in spec.
Bent decomp spring on exhaust cam for snappier action, shimmed left exhaust valve to .007"; bike kicks easier, this worked for one ride.
Checked starter gears, some wear on spur gear but doesn't look extreme. No wear on worm gear.
Rechecked valves.
Tried to roll start; nope.
Pulled tank and fuel injector and tested off the bike; good fuel spray.
Pulled spark plug and coil, kicked bike over and got spark.
Compression test shows 0 psi on two different gauges while kicking (forgot to hold the throttle wide open, will try again today).
Leakdown test shows 4% leakdown.
Cussed a lot.

Things I haven't tried yet:
Shimming left exhaust valve tighter than .007".
Replacing starter with brand new unit.
Adjusting idle knob at throttle body.
Cleaning throttle body.
Some have mentioned replacing a temp sensor at the back of the head?
Replacing starter gears; I called Bills, he's going to get back to me tomorrow.
Sprag clutch? Maybe it's dragging enough to cause problems?
Sheared key on flywheel could cause timing to go out???
Lighting this thing on fire, selling soul, and buying an orange bike...

Any help is appreciated! I may have missed something obvious. Hate to give up and take it to a shop, because I'm stubborn, cheap, and like to fix my own stuff as much as possible. Bike works great when it works...

you have two different problems (slightly related): the bike won't kick start (or run, even) AND the electric start won't start it either.

gotta fix problem 1 before looking at problem 2. so set the electric start issue aside for now

I'd say first off- put in a new plug... but your rudimentary spark test seems to have covered that. Yes, sometimes a sheared flywheel key will still spark. After redoing the compression test (with 4% leakdown, I'm not convinced it's necessary) pull the side cover and check it out.

I am assuming you've tried starting fluid? The fuel pump works (your injector test used it?)?

did this happen suddenly (especially after a stall or backfire)? I'd be guessing sheared key.

Forgot to mention plug is brand new.
I don't have the puller tool or flywheel holder, but I'm assuming I can see the key once that bolt is removed?
Tried starting fluid, no joy there either.
Fuel pump works, and was used to test injector off the bike (wired both directly to spare battery).
Seems more like a progressive gradual type failure. I was able to start the bike every time I needed to last ride, it just took a lot of kicking.

go ahead and try replacing the CTS ("behind the head"... actually, on the cylinder next to the CCTensioner on my bike). $20

I believe if you pull the flywheel nut you should be able to see the keyway [no one has ever reported back on this]. The misalignment could be insanely small if you sheared a key. But if your issue came on gradually, that reduces the chance of it being caused by the key.

FI test: did you pull the pump out of the tank? if so, maybe the fuel line or filter is cracked... naw, guess not.

A popular axiom- spark at the right time; compression at the right time; right amount of air/fuel mixture: it's gotta start. So one of those things is off.

good luck.

I agree 100%.

Check that woodruff key.

Usually when it shears it kicks back when trying to start because the spark is way out of time. Of course, if it ripped in half then it could be so out that it does nothing.

Take the nut off and check.

Get the Zip TY flywheel holder. You are going to need it.

I did pull the pump out of the tank and safety wired it down, as it had popped out of it's mounts. Certainly possible that I cracked something in the process, but the injector sprayed like a firehose when testing. Think I'll connect the tank up to the connector on the bike and see if fuel comes out the injector when I kick it. Could be a shoddy connector, or the injector/ pump isn't getting the signal to go. Will check the key when I get the tools as well.

Here's an odd suggestion. A TE250 I helped on recently wouldn't start because the sprag was stuck. The starter would turn the motor over to start it, then dragged it down preventing running. Just a thought...

Certainly not a bad suggestion- however, I gotta give props to the OP for suggesting it in his first post too.

I will point out that he couldn't bump start it either, which might preclude a bad sprag. but WTH, let's look at everything.

Forgot to mention above that I also replaced the starter relay. I noticed the old one had 20 amp fuses, and the new one has 30 amp ones.
I called up Bills and am going to get the new gears ordered, along with a new flywheel key just in case. Maybe once I get all that pulled apart I'll have a better idea of what's buggered up.

So, I kicked it a few times and got it to kick start, shut it off immediately, and couldn't get it to restart. I checked the battery voltage with a voltmeter while kicking and noticed it drop every time. Took both batteries to get tested and both tested good.

Took it all apart, no sheared key, no obvious failures. The flywheel definitely got hot at some point, but I'm guessing it's induction hardening from the factory, since nothing else looks discolored. Even the starter gears look ok, with minimal wear. Guess I need to double check cam timing and then start looking at electrical parts.

I doubt that your cam timing has changed unless you were in there. give it a look anyway.

I don't understand a few things: "shut it off immediately" (why?); "battery voltage... drop every time" (what?); "both batteries" (you have two? or a spare??); "took it all apart" (i'm guessing you took the flywheel off and found a good woodruff key). I can power thru most of it so it's not a show-stopper.

how did you get it to start- starting fluid? cold start knob? hair-dryer trick? if you have injector/pump/connector problems: spraying starting fluid should make it take off for a second.

What color is your cts? if it's black it might be a little more suspect. I am concerned about the spring and the ADC itself. You're sure about the fuel pump submersible hose, filter, and regulator it seems- but it's not totally clear.

the heat patterns on the flywheel might be a bit concerning (sprag again) but if you took things apart you're probably good in this area.

did you figure out why it wouldn't re-start (fuel? spark?)?

(starter relay probably doesn't have anything to do with kickstarting)

I've pulled the cams to reshim before, so it's possible that one or both are a tooth off.

I shut it off immediately because my kids were sleeping. I don't have much time to work on this thing while they're awake.

I hooked up the tank and injector back to the bike, but left the injector removed from the throttle body. I put a paper towel in front of it and fuel sprayed on it when I kicked, so I'm pretty sure the pump, injector, and associated wiring are good.

I had a voltmeter hooked up to the battery to observe the voltage while kicking. I noticed after every kick the voltage was lower. The battery was the first thing I replaced, so I had the old one and the new one tested.

I pulled off the flywheel, removed the starter and gears, removed the sprag clutch, woodruff key is still in the crank, but doesn't look damaged. I'm going to replace it anyways. I suspect the flywheel is heat treated from the factory because none of the mating parts look like they got hot. Would be nice to see a picture of a brand new one to be sure.

The bike started after just sitting for a while. I couldn't tell you why it started once and then not again. I did not use starting fluid, cold start knob (tried that after, no start), or any other trickery that time.

Starter relay is mainly for the starter itself, but there is another connector on it. Thinking that might excite the ECU and fuel pump? Need to look at the wiring diagrams. Could be something silly like a bad connector with resistance that's just a bit too high to work reliably?

It does kick more easily than before I messed around with the decomp spring. I could have bent it too far causing the decomp to keep the exhaust valve open at too high an rpm.

Give it a 1.5 second shot of starting fluid; don't try anything else. Now kick it good in neutral and see what happens.

Will try the starting fluid once I get it back together. I just checked and the coolant temp sensor is white. Can try and jumper it to see if that makes a difference. Recovering from stomach flu, so not too eager to hang out in the cold garage.

I've seen blue on flywheels before.

Since you reshimmed it check the valve clearance again in case something did not settle well.

Benny- any news?

Finally got it all back together over the weekend. I pulled the old starter motor out and took it apart again, only to find a couple of the windings sheared and falling out. Not sure if I created that problem when I put the new brushes in or not, but a new starter motor fixed it. Bike now starts reliably, but not easily. When rpms drop it makes a noise that's hard to describe. I'm 91.37% sure I bent the decomp spring a bit too much, and it's still "decompressing" right around idle speed. Next task is to pull the tank again and tweak the spring a bit. I'm not going all the way back to what it was, because I'm convinced that the spring preload was too low before, and it was hard to kick. I need to decide if I'm going to reduce the shim thickness by one size (back to stock spec) on that exhaust valve or not while I'm in there.

Well, I'm still fighting with this. I can get it to fire every time by wiring two batteries in parallel. Usually fires right up the first time, and then gets progressively harder. I had both batteries tested at the auto parts store, and both checked out ok according to their battery tester. I'm temped to get a Shorai and see if that does better.

Since my last post, I reduced the shim by one size on the exhaust valve where the decomp mechanism is. That puts it in spec, and back where it was to start with. I also tweaked the decomp spring back to where it was. Those two changes bumped the compression up from 60 psi to 65 psi according to my gauge. I'm messing with the Throttle Position Sensor and throttle adjustment settings now. TPS was set to 0.58V, and I adjusted to 0.68V. I don't have a good way to measure idle RPM at the moment, but I've read that 2150 is the magic number, rather than 1950. I tried a couple of audio based RPM apps for my smartphone, but they were worthless for this application. I do have a TrailTech tach/hour meter on my old bike, but it uses the spark plug wire for signal, and the Husky is coil on plug. How do you all measure RPM?

Does anyone know if the coils tend to go bad? I did see a spark when I checked, but I don't know if it's weak or not.

Just read another thread saying to wrap the Trail Tech tach wire around the body of the coil itself. Will rob that from the other bike and use to set the idle speed. I also double checked cam timing, and that's good. I disconnected the temp sensor on the back of the cylinder and it made no difference except the red led lit up. Jumpered the plug for it, no difference.

Maybe the condenser? Maybe I'll just bite the bullet and buy a third battery...

I think my mechanic (George Erl....Uptite Racing) secured a better ground on these bikes to help starting. 5 years ago so my memory may be faulty.
Something pretty easy to check.