Engine Trouble Bogging engine, little throttle reponse

[SchwinnAlloySeven_GT5]

YOU HAD A MAJOR TIMING MALFUNCTION and the force of your piston meeting the explosion head on popped your plug. This could have killed you if the barrel had exploded like large dirt bikes do when they severely over rev.

No, and you should find whatever you bumped your head on and unbump it!

Broken ring?

I'm thinking it may be so. I put the new CDI on today and no change. The problem has to be internal. I have a spare set of rings, but I don't have a jug gasket

Still out of commission for now

 

[gone_fishin]

you don't need one, use RTV high temp alone, put it on the underside of the jug for a cleaner job.

i have 200+ miles of trouble free service with this (thatsdax recommended) method & it looks like it's gonna keep holding

 

[SchwinnAlloySeven_GT5]

Well, I pulled apart the jug for nothing, it seems. There is nothing wrong with the rings, everything looks fine. There is no scoring on the cylinder walls and piston is relatively carbon-free. I don't have a clue what the problem is.

This bike is my main transportation and since it's been down, I've had to go back to 4 wheels and the gas money that goes with it. Any engine gurus with more ideas?

 

[Guest]

Is there something physically blocking the intake/carb/airfilter?

 

[1cc]

Sounds to me like the new spark plug lead could have a break in it. What sort of lead did you replace the original with. If it is a silicone one these break very easily. Replace with a wire lead & try that.

 

[SchwinnAlloySeven_GT5]

Is there something physically blocking the intake/carb/airfilter?

No. I checked the intake before I put the new carb on. In fact, the only way I could get the carb on there was to pull the intake, mount the carb on intake, and then mount the assembly back on the head. Clearance is very tight.

Sounds to me like the new spark plug lead could have a break in it. What sort of lead did you replace the original with. If it is a silicone one these break very easily. Replace with a wire lead & try that.

At first, I used a new automotive silicon wire. I had issues immediately and put a new copper-stranded wire on there, just like the original. The boot is a new NGK, as well. It started easier, but it still didn't do anything right but start and idle.

I got in touch with an old friend of mine who has a lot of magneto experience. He asked me if I replaced the magneto rotor and I did not. Well, after putting the jug back on and replacing the rotor, the engine won't fire anymore. I know the rotor is on the right way, and I'm sick of messing with it right now. POS.

 

[MotorbikeMike]

magneto rotor

Hello, there are only 2 things to know about magneto rotor:
A) installed correctly in proper direction, key in keyway?
B) Has magnet lost it's permability???
test magnet with 1/4 flat blade screwdriver, if the blade on the flat is really "stuck" on the magnet, ok, if you can almost "bounce" the blade on and off the magnet......replace it, REMEMBER the north pole is usually noticibly stronger than the south, this is normal, Mike

 

[ibeenjammin]

I am having similar problems as the original post, although I never lost my spark plug, nor herd a loud pop. Throttle response is just very slow/sluggish all of a sudden, it seems like it takes forever for the engine to warm up. I have replaced the intake gasket twice now. the bike just doesn't have the pick-me-up it once had. Please update us on your bike, has anything improved yet? My bike feels as though I am not getting the compression that I once had. I am going to try the beer can trick on the intake manifold and the washer as well. I hope it fixes my situation.

Ben

 

[Poodlebombs]

Wow, I have the same problem. I already rigged up the beer can and popped an o-ring in the sucker, still having problems. Throttle/rev is incosistant with my accelerating. I dunno what's going on, and i'm still in break-in.

The carb is too tight of a fit on mine as well, so I flipped the intake upside-down and mounted the carb on straight. I didn't suppose it would effect anything, but the angles are a little different with the intake upside-down. I don't think this has an effect on my problem, but could this have any other side-effect? or negative effect on the engine?

 

[gone_fishin]

when the engine's warm, choke it...if it doesn't die right off there's still an intake leak somewhere. if it revs at 1/4 choke, mixture might be set too lean.

check this section out: http://www.motoredbikes.com/forumdisplay.php?f=88