LC4 Won't start

[dlh62c]

Way...Way COOL!

Take notes as your doing this and measure out the new parts, This will give you a baseline for any future problems.

daryl

[Supervaca]

Thx Daryl, as i said earlier, i might not like it right now but i sure am getting to know my bike. I have all the values in a spreadsheet for later use.



So, i finally got her started and ran her a bit (10 minutes) and I lost a LOT of oil into the air box.

The bike feels very weak and still can't start unless i tow it.

The big question is, why am i getting all that oil in the air box?

and is the LC4 motor supposed to blow really hard out through the breather hoses (connected to the horizontal frame tube connected to the air box).

the oil level was spot on before my 10 minute ride and is way below now.

Could the cam timing be off by 1 tooth making the bike weak and hard to start? or would it be impossible for it to run if it was off?

Thanks
DuP

[gunnerbuck]

I don't like to be the bearer of bad news but from what you are describing it sounds to me like your top end is cooked... First thing would be to do a compression check in the form of a leakdown test... You will likely find compression lacking due to piston/cylinder damage... You may be able to peer through the spark plug hole with a flashlight to see any visible damage on the piston crown....

Hopefully it's not the above and something with simple fix...

[Supervaca]

Well, got the top and cylinder off today, let me just warn you that the followinf images are not for the faint of heart..



and




that explains a lot of the problems i've been having, top ring has shattered and been spit out through the exhaust. Looks like the bottom ring and the oil ring are ok so i hope no debris has found it's way down.

All thats left is to order neew parts and put it back together.

Thanks for all the help

DuP

[markamazing]

I bought it used off ebay for $200. and $75. for shipping. I was pretty impressed with the cost of an OEM piston, rings, wrist and clips.
The barrel was fine and the head was beat up like yours. I intend to re-build with same head, but new piston, either wossner or proX, depends on how rich I feel at the time. I will do a complete tear down to look for additional debris/ damage.
good luck

[bmwktmbill]

I don't think the ring shattered, I think it got hot because it lost water or lost lube, then the ring broke...how's the connecting rod for play, big/small end?

I'd say the cooling system failed but I could be wrong.
Often am.
bill

[5-0 BAIT]

I've got just about the same problem. Only, I've had shops doing all the work for me. When I first brought the bike in, they put in a new spark plug, and cleaned the carbs. Another shop figured out that there wasn't a whole lot of compression. So, they put in a new piston kit, and a new stator. Now it's getting plenty of compression, but still won't start. So, they traced all the wires, and figured out there's no problem there. So, now they've put in a new CDI, and they're putting in new coils. They also said that with the spark plug out, there's sparks flying everywhere. But, when there's compression... no spark, and the plug comes out "wet". It seems like they're on their last leg, and this happens to be the 3rd shop I've taken it to. The first shop said "that's normal, just jump start it." Well, I'm 5' tall, and I can't jump start this thing by myself.

P.S- it's an '04 KTM LC4 (625 CC) with an aftermarket supermoto electronics kit.

Any help would be appreciated. I've already spent about $2000!

[gunnerbuck]

Originally Posted by 5-0 BAIT

I've got just about the same problem. Only, I've had shops doing all the work for me. When I first brought the bike in, they put in a new spark plug, and cleaned the carbs. Another shop figured out that there wasn't a whole lot of compression. So, they put in a new piston kit, and a new stator. Now it's getting plenty of compression, but still won't start. So, they traced all the wires, and figured out there's no problem there. So, now they've put in a new CDI, and they're putting in new coils. They also said that with the spark plug out, there's sparks flying everywhere. But, when there's compression... no spark, and the plug comes out "wet". It seems like they're on their last leg, and this happens to be the 3rd shop I've taken it to. The first shop said "that's normal, just jump start it." Well, I'm 5' tall, and I can't jump start this thing by myself.

P.S- it's an '04 KTM LC4 (625 CC) with an aftermarket supermoto electronics kit.

Any help would be appreciated. I've already spent about $2000!

If you have good compression, good spark , reasonably close jetting and the bike still won't start then it is possible that your starter clutch is slipping and possibly not allowing the engine to spin over at a fast enough rate to light the fire with the E button...

Did you have it running before with the aftermarket Electronics or is this a recent non tested installation?

[MORT666]

PUT a yam 660 motor in it.

[achile]

Originally Posted by MORT666

PUT a yam 660 motor in it.

Take the front end and put it on a Xr650r

[bmwktmbill]

5-0,
Where are you located, you need to find a good mechanic by the sounds of it or an inmate to help.

bill

[Beemerboff]

BMWs had a lot similar problems-some were caused by dud starter and load control relays, some by corrosion on the pins of the relays.

[5-0 BAIT]

Awesome, thanks for the advice guys. I'll check the starter/relays/pins next. I'm in Hawaii (Oahu). So, it's kinda hard to find someone here who knows about LC4's; I've only seen one other on the island, and it belonged to a pilot from Austria who is only here like one week out of the month. lol Also, I've tried all of the good mechanics on the island. So, if the starter isn't the problem, I'm just going to take her home and tinker until she growls right. I'll keep everybody updated on it. Thanks again.

[5-0 BAIT]

To answer Gunner... One of the things the shop did was take all of the aftermarket electronics off, and try it as if it was a straight dirt bike... no dice. One of the strange things is, when I first got the bike, it would crank, weakly, but only if the hot-start was on.

[gunnerbuck]

Originally Posted by 5-0 BAIT

Awesome, thanks for the advice guys. I'll check the starter/relays/pins next. I'm in Hawaii (Oahu). So, it's kinda hard to find someone here who knows about LC4's; I've only seen one other on the island, and it belonged to a pilot from Austria who is only here like one week out of the month. lol Also, I've tried all of the good mechanics on the island. So, if the starter isn't the problem, I'm just going to take her home and tinker until she growls right. I'll keep everybody updated on it. Thanks again.

The starter clutch sits behind the flywheel on the right side of the engine...
With the spark plug out there is much less compression drag on the engine so the starter will more easily spin it giving a strong spark... When the plug is in the extra compression drag could be causing this starter clutch to slip, in turn it will not spin the engine fast enough to produce a proper ignition fire to start the engine...

Here is a thread:http://www.advrider.com/forums/showthread.php?t=222515