BASIC MECHANICAL PROBLEM>>

OK Don.. or Chris.

my jawa.. 77.. firing, its got gas ,, and compression.. but after about three minutes. it dies to a stop.. and then won't start.. i'm trying to problem solve this.. but i think its an experience thing.the carb is clean ready to go..i'm thinking its the rings.. i haven't had to changes the rings on this bad boy or any of my bikes.. but is that a typical sign. of bad rings.. i know you guys aren't familar with the bike.... but this problem i think can apply to any bike.. its not electircal.. ether.. what about the clutch? as for centrifical clutchs go.. i just put some make shift pads i got from a clutch place.. and they fit great. a litttle tight right now. but i think after they wear down and be fine.. could that be the problem.. i mean the clutch is really tight.. could it be killing the engine.. cause it gets to tight. because of heat. and can i foul a plug.. but it still be brown.. and have spark.. i mean.. my other bikes .. are running solid. I feel good about my mechanic skills. but this thing is pissing me off.. i just can't seem to figure this thing out.. check out . what i working with ^^

brown..

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Re: BASIC MECHANICAL PROBLEM>>

Jason Luther /

is your carb flooding?

Re: BASIC MECHANICAL PROBLEM>>

nope.. it starts on the first kick.. after its been sitting over night.. with the gas lever on..' i though it was that. at first.

brown

Re: BASIC MECHANICAL PROBLEM>>

i developed a similar problem on a PA50.. the bike restarts with some peddling and a wide open throttle. This problem started right after i cleaned the carb last night.. very weird.

I get the strong feeling that my needle is sticking closed...

The float bowl starts out full, the float drops but the needle is stuck, and the bowl empties to the point where the float level is low enough that the engine dies (at idle). Then as i peddle and twist the throttle and generally shake the bike the needle drops and the bowl fills again.

Here's what i suspect is happening..

The needle attachment to the float is loose and has some free play, so the float has to drop so low that it actually pulls the needle open. But by this point the idle circuit is too lean to idle the motor.

Right now im doing some mechanical work but later i'm gonna pull the carb and see.

Re: BASIC MECHANICAL PROBLEM>>

I would take a spare spark plug with me, and when the ped dies, pop in the other one and see if it will work. If not, check the plug and see if it's wet from gas. It almost sounds like overheating...my Peugeot used to die after 20min of riding, and I couldn't start it again-turned out to be an air leak around the intake.

Re: BASIC MECHANICAL PROBLEM>>

intertesting.. keep the sceniors going.. I'm gonna try it all.. Its all about experience with thes things.. so much could go wrong in such a simple bike..

i don't think its the crab.though.. brown.. its a solid dellorto. brown

Re: BASIC MECHANICAL PROBLEM>>

well.. my problem wasn't carb related but it was gas related.

Pull the plug and clamp it to the head and see a nice fat spark. The thing started fine on Starter Fluid (ether) in the air intake.

Is there gas in the float bowl? Open the drain plug and gas pours out. Close the drain.

wth.. i just cleaned this carb.. could it be a clogged main jet? got gas and got spark and got compression.. hmm.

Drop the motor to access the carb and pull the gas line off, all prepared to catch the fuel still in the line with a can. No gas. Turn on the petcock and still no gas??

damn.. how dumb is that? :)

but wait.. i know theres gas in there (err.. im pretty sure?) So I blow in the end of the line to hear the bubbles in the tank and 2 seconds later i get gas all over me. So, while draining the gastank i see that the flow is getting slower and slower..

First thing i did when i got this bike a week ago was clean the filter and screens in the petcock.. now i guess i gotta get serious >:|

Re: BASIC MECHANICAL PROBLEM>>

i got lucky. After checking the tank screens again and see they are perfect, it must be something else thats stopping flow.

This tank had been Kreemed and, as a bonus, the guy kreemed the gas cap too.. so, no vent! I guess the only venting must have been coming from the cracks in the old rubber gasket inside the cap. So when i blew into the gas line i pressurized the tank and then gas came flying out.

I coulda sworn this bike ran great but maybe it will get better.. It got up to 30mph real fast the two times i tested it.. Unfamiliar bikes are hard to judge and diagnose..

Re: BASIC MECHANICAL PROBLEM>>

I'm not sure... if your last post helpped me..

but i'll check my carb out again.. its totally get nice fresh gas though..

we will see. i got some time today. to get progressive..

brown

Re: BASIC MECHANICAL PROBLEM>>

well.. maybe it is the clutch pads..

you mentioned ".. i just put some make shift pads .." on the bike and they are tight.. Are they overheating the clutch and maybe this is overheating something else and causing too much friction.. It's hard to say but why guess about it.

Waiting for the pads to wear down might take a while since pads are designed to wear down real slow :) So, first thing i'd do is get some sandpaper and grind the pads down till they do not drag at all. This will eliminate one possible reason for the problem.

But i think you already thought of that and cannot grind the pads down for some other reason, like the rivets are already close to the surface or something.. They do make bonded pads but i dunno what kinda glue they use to bond them. Maybe it's available. I guess they probably put the pads in an oven to cure the glue.. maybe i'll research this if i find some time since i would like to know..

Re: BASIC MECHANICAL PROBLEM>>

joe..

if you can believe. it

one little spec of rust causing mad chaos.....stuck in the line..

right after the hose .. going into the carb.. i'm talk like . BIg

just a grain. sillyness these mopeds sillyness. brown

Re: BASIC MECHANICAL PROBLEM>>

yeah, i believe it.

when i found this bike at the salvage yard i saw the Kreemed gastank and the inline fuel screen .. so you just know the previous owner had lots of carb trouble. The nice thing was only 500 miles on the speedo. I guess the guy got tired of it or something.

Tank is rusted bad and has a epoxy patch on the bottom (probably JB Weld). So far the Kreem is keeping everything clean but i know i gotta eventually open the tank, sandblast and coat the inside, and patch the holes someday. It will be a nice project since i never did it before.

But at the salvage yard he had lots of plastic tanks for all sorts of bikes. Sure would be nice to get a plastic one but then again i guess they have their own problems.

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