So... I bought a Hawk off Craigslist

[jet321]

Originally Posted by mdyates

Great advice, thank you guys. Getting frustrated though... New Mikuni VM26, nice spark - getting fuel. Valve clearances are in spec yet NO combustion!!! Not sure how this is possible. I've had countless dirtbikes, go karts atvs over the years never seen something that won't fire/combust with starter fluid etc...

I don't know if you got a clone carb but the jets may be clogged and like merlin said, I would check compression as well. My bike had issues and it turned out to be a bad battery, she was getting spark (weak spark at that) and was getting fuel.

Have you tried kick starting the bike?

[JerryHawk250]

Originally Posted by Merlin

Have you checked the compression yet?

I have always brought my gauge with me for every time I have bought anything with a motor. Some people were insulted that I would bring a gauge. I can remember buying a 20 mercury outboard and the guy swore up and down it had good compression. When I asked him if I could check the compression he was like , what you don't believe me? I told him i'm not buying unless I check it. He want $1500 for it. So when I checked it sure enough it had one bad cylinder. I picked it up for $100, did the repairs for $125 and them sold it for $1500.

[BlackBike]

If you cant find your way, that avenue that you don't go down will always be the correct path.

Captain Obvious

[letsride]

Air, fuel, Compression, spark (AT THE RIGHT TIME), and it has no other choice but to run. Put a new spark plug in it also.

[mdyates]

Thanks guys, bringing home a compression tester. Will let you know what it is. Just bought an Iridium plug and will try that too. If it has compression, my only thought is weak spark. I am using a battery tender booster so has plenty of volts.

[Ariel Red Hunter]

Originally Posted by mdyates

Thanks guys, bringing home a compression tester. Will let you know what it is. Just bought an Iridium plug and will try that too. If it has compression, my only thought is weak spark. I am using a battery tender booster so has plenty of volts.

Didn't you tell me that it had a nice blue spark at the plug? If it turns out to be low compression, try shooting some Marvel Mystery Oil through the spark plug hole in case you've got a stuck ring on the piston. Let it sit for a couple of days and see if that doesn't free it up.

[mdyates]

Compression tester wasn't right size for plug.. So, installed new iridium plug and fresh starter fluid. Backfired thru carb and started a fire lol. Never really started but hoping this is a good sign pointing towards bad timing? Could it be a bad CDI etc? Something to note, my cranks breather popped off due to pressure and pumps out white smoke whilst trying to start.

[Merlin]

Stuck float bowl?

[timcosby]

Originally Posted by mdyates

Compression tester wasn't right size for plug.. So, installed new iridium plug and fresh starter fluid. Backfired thru carb and started a fire lol. Never really started but hoping this is a good sign pointing towards bad timing? Could it be a bad CDI etc? Something to note, my cranks breather popped off due to pressure and pumps out white smoke whilst trying to start.

not a mechanic but i think that is what backfiring thru the carb is a symptom of

[bogieboy]

if the case breather popped off and you're getting white smoke from the case, I'm fairly certain your rings are bad...

[Ariel Red Hunter]

Originally Posted by bogieboy

if the case breather popped off and you're getting white smoke from the case, I'm fairly certain your rings are bad...

Yes, and if they are stuck, try putting a couple of tablespoons of MarvelMystery Oil down the spark plug hole, and let it sit for a couple of days. Rings are probably stuck from sitting. Prop the bike up so that the engine sits level, that way the MMO works all the way around the piston and rings. After two days, or so make sure the spark plug is out before you crank it. It has to blow the excess oil out of the combustion chamber to avoid a hydraulic lock. Then try to start it again. Let us know what happens.....ARH

[letsride]

Here's my early morning thinking over a cup of joe. Whoever bought the bike probably quickly assembled it and rode the snot out of it. And since most folks report their Hawk came with TIGHT valves, the non existent maintenance probably killed the bike. I would check that valve train, while you do what Ariel suggested (soaking the cylinder). There is a video my motocheeze on youtube of how to adjust the valves. Doing that procedure will also let you know if the timing is in the ball park. Its either no compression, or valves not closing, bent, etc. Where are you located? If you were close to me I would have no trouble coming and giving you a hand, you provide the suds of course. Good luck and keep us posted. This is the kind of thing that gets my gears moving, bringing bikes back from the dead!

[LunaTech]

Yea, let us know the area you live. You might have a fellow Hawker that lives close to you that can lend you hand getting her running. Here is a link to all of the video MotoCheez has made. His videos has help MANY of us out.
https://www.youtube.com/playlist?lis...IupPrEXyhXU9QN

[mdyates]

Thank you to everyone for the help! I live in Orlando FL. I will do the required soaking and re check valves. Also hoping I can do compression test as well!

[Ariel Red Hunter]

Originally Posted by mdyates

Thank you to everyone for the help! I live in Orlando FL. I will do the required soaking and re check valves. Also hoping I can do compression test as well!

The old fashioned way to do a compression test was to wedge the throttle wide open, jam your thumb into the spark plug hole, and crank the engine. If it has got decent compression, you won't be able to hold your thumb in or on the hole.