motobecane

just bought this moped last week and i been working on it. getting nowhere. anyone have any experience with these that can help?

all i know is its a motobecane. i bought and installed a cdi unit because the old wiring was basicly trash and my points were missing. i do have spark now. and ive been working on this carb. but i take carb off and spray carb cleaner directly into intake still cant get this thing to fire yet.

any help would be appreciated.

thanks

jack

Re: motobecane

Dirty30 Dillon /

What are you timed at?

Re: motobecane

i dont have a timing tool but i used a long bolt and its right before tdc. i cant tell exactly but for sure less then 1/8.

will taking plug out and spraying carb choke cleaner to get it to fire work? cause it doesnt pop spit or sputter just dead.

im also trying to start it using 14mm socket on a drill in reverse on variator nut.

i got tired of pedaling.Edited 1 time(s). Last edit at 01/31/19 08:15PM by keecho.

Re: motobecane

Richard Eberline /

brake cleaner and Carb cleaner eat up rubber.

Set the timing, if you use anything, starting fluid. Use wiki for timing and cdi.

Re: motobecane

if im getting spark then cdi and wiring is ok right? i should rule that one out?

i just ordered some kind of carb party from treat, like a newer carb with cable and intake etc. so soon i can rule that out also.

im guessing i need to order a timing tool to be exact. other then that not much left to try in the meantime? any ideas? or should i just wait.

thanks

Re: motobecane

Dirty30 Dillon /

My guess is that you are not timed properly.

Re: motobecane

u need a timing light to time the motor.

Re: motobecane

i have a timing light. i just use it just like a car? can i use external battery to simplify?

and one i see my mark, i just pull of stator rotate/adjust and put back? never thought of a timing light.

thanks

Re: motobecane

read in wiki how to time cdi in wiki look up timing cdi to read and think about taking a look at wiki entry under timing with cdi unit, its confusing but try different methods cuz one method may make sense to someone but not to all brains.

Re: motobecane

yes to separate battery laying close but not in danger of moving parts think about how to kill bike so it dont rev to moon uncontrollably, sp

Re: motobecane

If the engine was sitting for years, your rings might be stuck in their compressed state. Without compression, it wont matter what carb or ignition remedies you try, it will not fire.

Re: motobecane

yea its been sitting 6-7 years at least maybe a little more. but i did check compression with the same drill tecnique im using to try to start. i get 60psi on drill speed 1 and 100psi on drill speed 2. im not sure why speed is making a difference? maybe i have an air leak that cant keep up with drill speed 2 ?

not sure yet. but if i dont get it to start with the new carb in the mail, ill order a rebuild kit and go through it.

any worth upgrades i should look into if i end up going that route?

thanks again

Re: motobecane

Alan Jackson /

I once owned a motobecane (gave it away for free in 1990!!!)

very simple bike to start on to learn how to dismantle and rebuild with new cheap parts.

if it has been stood for a long time then rust can get into the bearings and first time you ride the bike in anger you could get a massive (expensive) failure

or like has been said before rings could be seized. crank seals could have perished too.

I understand if your not into the mechanics side and just want to fuel up and ride you will want a quick fix.

but sometimes stuff isn't half as hard as what you imagine and there is loads of help/ info online/here

and there is so much satisfaction to be had doing it yourself.

although when it comes to my car/van I am happy to pay someone else...

Re: motobecane

got the new carb saturday i think its a deltora 1.5 or something? also came with intake and new cables. should i install it and try to get it to start or should i just drop the engine and order new rings crank bearings, gaskets and seals.

not sure here. i doubt its going to start at 50-60 psi. i know there is a big air leak somewhere. the other day i put some oil in the plug hole just to get things a bit lubed up and most of it drained out of my stator while turning over, which leads me to believe the crank seal on that end has the biggest leak so it just ran out of there. not ran but dripped i should say. reguardless i dont think she will fire up.

Re: motobecane

unless yr superman, id suggest taking pictures as u take apart stare at it ask some questions w appropriate pictures and then put the order in.

Re: motobecane

got it started. so i installed new carb, routed new cables, choke and throttle, opened my fuel valve put my drill on the variator and started cranking choke on off throlttle open close trying everything then i get a backfire so wow my first backfire. ok checked adjusted timing, more backfires, checked adjusted timing vroom high idle adjusting throttle cable, wont idle low, dies. use pedal start back up first crank, vroom adjusting throttle cable, wont go low idle.

so heres where im at.

cant get it to idle with throttle cable asjustment. its eighter to low and just dies or too high and sounds like its gonna fly away. also have a very loose exhaust pipe and rattle, i can fix the rattle but im pretty sure its leaking at that big nut. took a big wrench to that nut and cant get it loose.

how do i adjust the idle? its an sha delirto carb from treats. and best way to get that nut loose so i can shim it.

thanks

Re: motobecane

Alan Jackson /

i'm no expert but I think you are wasting your time trying to get it running right if the crank seal is gone and that means an engine stripdown.

I do know some folk have changed seals without stripping the crankcases but if I were you I would renew the main bearings and get someone to check the crank. or do it yourself?

to fully rebuild it would not break the bank and there are loads of how to's on here and online.

Re: motobecane

I already ordered new bearings seals and gaskets and one piston ring I just want to get the bike running in the meantime

Probably a waste of time but least im learning. i need to get that exhaust nut off reguardless and i ordered a 58 jet today. found out the one that came in kit is a 70.

could tgat cause the high idle?Edited 1 time(s). Last edit at 02/06/19 03:20PM by keecho.

Re: motobecane

kevin Smellaflange /

spin the motor with your drill, check your comp release,

put an old hollow rubber foot peg in between your belt & rear pully thus variating the moby motor backwards giving you the room u need....et voila

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