Hobbit help needed!!!

I have a Honda Hobbit that I installed a 70cc Athena kit, 21mm dellorto, boyseen carbon fiber reeds, I have a good spark, good compression, the problem I am running into is that I dont seem to be getting fuel into the cylinder. I have tried putting a tablespoon of fuel in the cylinder and even tried a lil startring fluid with no luck. I do not have the decompression cable hooked up but I have tried pushing the valve in while pedaling it to start it. It has the original head which seems to have the compression up there for sure, if I dont have a heart attack pedalling this thing to get it started it will be a miracle!! If there is anyone I could crate the engine up and send it to to get it running I would even do that if I have to!!!! Any help is greatly appreciated!!! I posted some pics so if you guys see anything I could have done wrong lemme know please~


Re: Hobbit help needed!!!

Couldn't keep my eyes off the floor, what kind of 'ped is it???

Turn idle screw in all the way..

Or change slide to a 60.

What main and idle jet you got...?

Re: Hobbit help needed!!!

You ran your air intake into the frame? weird. I wonder how you did that.

The stock head is modified isn't it?

You didn't use the stock studs did you?

I have heard the athena isn't a beginners kit. Did the intake and exhaust open up fully? If you have fuel, air, spark, and compression - either you have weak spark, timing is off so it wont fire at the correct time, too much compression, or too little.

The hobbit timing you can't really mess up unless you pull the keyway or gap your points like crazy. Is yours Points or CDI?

so when you shoot some starting fluid the motor doesn't even fire up off of that?

Re: Hobbit help needed!!!

I will haf to open it up and see, its brand new never had fiuel in it til now, whatever the stock jets are. Its a 78 honda hobbit with a 70cc athena aluminum jug, ill ck the mains and try and turn the idle screw all the way. I tried turning it a lil but nothing yet....just one or two backfires.

Re: Hobbit help needed!!!

Yeah I have tinkeritis....I made a home made ram air system for it, ran a tube down the frame and picked up air at the top thru a vacuum attatchment I fabbed up a fiberglass mount for it which I am going to mount my ignition switches etc and a trail tech if I ever get the thing running. lol It will run on just til the starting fluid goes away then nuthing. The plug is dry if I try and start it without introducing fuel manually thru the plug hole. The head is a stock unit that I had to clearance to make the 1mmm clearance recommended between the head and piston. I checked this using clay and taking the head off and on a hundred times after grinding the head a little at a time.

Re: Hobbit help needed!!!

After a rebuild, i always turn the motor over without a spark plug for a bit until I'm sure I've got gas up into the cyl. Then install plug and go.

If you added gas and no fire, it's either spark not at the right time, or maybe your frame air intake is restricting. Using "stock" jets without paying attention what they are is a good way for you to either seize or not start.... Gotta choose that shit...

Re: Hobbit help needed!!!

"ram air" is a bad idea on 2 strokes.

It will really mess with your mixture and could cause you to run very lean at speed. Don't bother.

Get gains from porting/better reeds/tranny tuning.

Re: Hobbit help needed!!!

Well the ram air is really for looks mainly, the tube size is relatively small which I will hope is gonna give me more velocity than volume and I hope to tune the system a little on the rich side idling so it will be safe when wide open throttle. Its just for looks but im hoping for a little performance but if not ill block it off and use a side mount air filter. Im just gonna be happy to hear the thing run!!!!

Re: Hobbit help needed!!!

I doint know if this matters but I did away with the factory harness and just wired the four wires comingg out of the engine and used a on/off rocker switch which I will mount on my homemade dash if I ever get it running. So if anyone knows if I may need something wired into this let me know.....thanks for any help!!! If anyone knows of a shop I could send it to to get it running and maybe install a aftermarket ignition system I would be interested in that too.

Re: Hobbit help needed!!!

Emil Kniemel /

can i have your old harness?

edit: you may or may not need that silicon rectifier box thang thang (edited)

Re: Hobbit help needed!!!

I did wire in the silicone rectifier but any of whats left of the harness you are welcome to. There isnt much but what there is all you have to pay is the shipping which shouldnt be much. Just let me know. I can send pics if you want.

Re: Hobbit help needed!!!

New dellorto? only runs on starter fluid? Its not flowing gas then I think dells have floats of some sort. Make sure its within spec and the needle is opening, bowl is vented. Right?

Got your pm btw! If your decomp valve is hitting your piston that makes me think your squish is way too small also.

To check squish _ take your plug out _ take some solder, and bend it into an L, then put the L in the spark plug hole, you hold one end of the L and the other end of the L goes to the cylinder wall. Turn the flywheel by hand and it makes an imprint of the solder ( plumbers solder is fine ) then you use a caliper to check it.

You could get a nice head made from Graham

here is some ram air theory from other d00ds

They pressurize the gas tank. Just like how the bowl is vented to the airbox so it gets the same amount of pressure as the carb's inlet, this is to reduce backflow through the main jet, so is the gas tank. This keeps the bowl fed with fuel as the pressure on each side of the float pin is now equalized, this lets gravity do it's job just as it would without ram air. There is however something called air box seize. This is when you're gas tank's pressure line comes off causing the bowl to run dry causing the engine to lock up.

Re: Hobbit help needed!!!

Beard Road Bruiser (SoB) /

+1 on the Graham head. His shit is the bomb.

Ditch that ram air, you don't need it or want it.

Pull the plug and check for spark by holding it against the cylinder (make sure no gas around or you will blow up). Nice fat blue spark? Yes? Good, go on to the next step. (No? check points, coil, plug, and wire/boot)

Hold your finger over the spark plug hole and have someone turn it over. Is it pushing against it pretty good? Hopefully so, you have compression.

Lastly, throw a shot of starter fluid in there and kick it over with the plug back in. If it doesn't go, I dont know what to tell ya. Hobbit's timing is fixed, so it has to be the plug gap at that point. Check that.

Re: Hobbit help needed!!!

Hes running on the starter fluid but it wont keep running (from what I understand here and from your pm)

If you had a mikuni/keihin you could crack the bleeder screw on the bottom of the bowl to see if you had fuel flow. this phbg stuff I d K

Re: Hobbit help needed!!!

Beard Road Bruiser (SoB) /

Oh, the first post said "tried starting fluid with no luck". I assumed that meant directly into the cylinder.

Re: Hobbit help needed!!!

paul LOUISOS Wrote:


> It will run on just til the starting fluid goes

> away then nuthing. The plug is dry if I try and

> start it without introducing fuel manually thru

> the plug hole.

That is where I got my information

>The head is a stock unit that I had

> to clearance to make the 1mmm clearance

> recommended between the head and piston.

Two stroke tuning book recommends something like .6mm squish for clearance. a good squish will keep you running Cool

Re: Hobbit help needed!!!

I have a nice bright blue spark, The compression is excellent, I just wonder is the petcock valve I installed being almost lower than the inlet on the carb could have anything to do with it? It will run on while cranking with the starting fluid....just making it easy to pedal, not actually firing up until the starting fluid runs out the its hard to pedal again. I( have no ideas left..... When I insttalled the reeds the two petal thin metal piece I removed is not installed with the carbon reeds correct?? Its like it isnt getting fuel into the cylinder, the plug isnt wet by any means unless i spray the crap out of it.

Re: Hobbit help needed!!!

If you know of any reputable moped shops within a few hundred miles of southern WV I would take it to them, im desperate to get this thing running! I originally built the moped for my brother who has been in the hospital and he is getting out next week and I would love to have it ready for him to ride when he gets home. The smile on his face would be well worth whatever I have to pay to get it running.

Re: Hobbit help needed!!!

use and external fuel tank. Strap the hobbit tank to the rear rack.

Re: Hobbit help needed!!!

Any updates on this? have you had a chance to tinker with your carburetor Paul?

Was the hobbit running before you put a kit on it?

Re: Hobbit help needed!!!

UPDATE!!! Its running!!! Not perfect, but running!! The main issue I have is that it only runs with the choke on, which I assume is due to an air leak? The easiest way to track this down is using starting fluid, any combustible fluid or gas and search for it that way. It looks like when I accelerate I can see exhaust coming from between the cylinder head and jug?? I just used the new gasket with no sealant, I am going to try some copper spray or if you guys know of some other remedy im open to opinions... I have a brand new phgb 21mm carb with no air filter at present time so I know i need one installed to tune correctly but I rode it with the choke on and of course it wont idle but seems like its going to run good once its tuned.....help!!!

Re: Hobbit help needed!!!

Emil Kniemel /

why not get an airfilter?

Re: Hobbit help needed!!!

Didn't read all the posts, but did you replace the crank seals? If not that might be the solution to your idle issues.

Re: Hobbit help needed!!!

Use anerobic sealant on jug and aviation gasket shit from permatex on head.

Used to be called super300 permatex.

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