Hi,
I just purchased a 1978 motobecane - i just love it! The guy i bought it from said that it could reach a max speed of about 35mph - but i can only get it up to about 22mph???? Is this normal? Or does it need some adjustment?
Any help would be greatly appreciated
Thanks,
Cathy
It could be any number of things. Could be that your exhaust pipe is plugged up (when it idles is it a brrrrrrrrrr sound or a pop pop pop sound?)
If you have a model with a variator (lucky for you if it has one) it could be that the variator is not adjusting to the right ratio to achieve top speed. Could be that you put too much oil in the gas tank when you filled it up.
Hi Nathan,
When i first start it up i hear a pop pop sound coming from the exhaust - i just bought it 2 days ago so i haven't had a chance to take it on a long ride - i'll try that and see if the speed gets any better.
I'm not sure of the oil to gas mixture since i just got it. I'll also check on the variator - if i have one? if i can locate it?
thanks,
i'd clean the carburetor out too, just to start fresh. the variator is on the left side, its round, metal and spins when your engine is running. if you take your side covers off you'll see that the belt connects to it. rev your engine while it's on the kickstand. if it contracts in and out (you'll know what i mean) then its the variator. if not, its just the standard.
i know this sounds really stupid - but how do i clean out the carburetor? this is all new to me - but i'm pretty good at following directions and not too afraid to get my hands dirty and take things apart ..
i'll check on the variator ..
no i gotcha. trust me its not wicked hard. take your side covers off. The carburetor is connected to the cylinder by the intake manifold. The carburetor mixes fuel/air and delivers it to the cylinder via the intake manifold. It should have a black plastic box (the airbox) connected to it. As long as you have a screwdriver, socket set, basic tools, it becomes fairly apparent what needs to be unscrewed to take the thing off the bike. Note: you will have to take out a screw where the throttle/chocke cables enter the top of the carburetor. Then, take the carburetor completely apart. It may be intimidating if it's your first time, but just do it slowly and remember what tools you used to take what off, and where everything goes. From there, use Carb Clean (3 bucks for a can) with and without the straw and spray out EVERYTHING. every orifice and whatnot so theres no dirt, grime, rust, etc. if its real bad use a rag, toothbrush, soft cleaning tools. Maybe you'll be lucky and it will already be pretty clean, but there's no point not cleaning it anyways. Then put it all back together with careful attention to detail, making sure everything is where it started. heres the parts breakdown: http://www.themopedjunkyard.com/gurtner.html. Good luck.
-Steve
First go to MRA for the manual
http://www.mopedriders.org/article_cat.php?fldAuto=2
there are two repair manuals Motobecane and Mobylette listed there also an owners manual. Very important links to have because the manuals show pickys of stuff apart or basic how to do stuff.
Also search this forum and the repair forum. Most problems have been asked and resolved by other moby owners. Mobys love to be driven lots and maintained a bit, but they are the sexiest mopeds ever so it is definately worth the effort.
DO NOT BE FREAKED OUT about getting your hands dirty, I always tell everyone that repairs are so easy even a girl can do them - _I am allowed to say that_ lol
second that on them being sexy.
on the front of bike is a label it will have a letter
if it is a then you have a 30 mph if it is b then its 25 mph
if c then 20 mph
I finally looked and saw the disappointing B - so i guess it's normal that i can only get it to go about 22mph - and a bit faster going down hills ...
actually now i have other concerns - my chain just broke today - darn it! - so i'm looking for a replacement chain and a few tips on how to change it .. auugghhh
Chains dont break, the master link just comes off because the clip is on backwards or was messed up by someone who installed it. Get a new link #41 and a spare or a whole new chain. The link will be about $1 and the entire chain $12 for 10 feet - more than enough. When you put on the replacement master link make sure the round part of the U faces the direction the chain travels or it will pop off ant the worst time just like you experienced - and there is no way you would ever find it on the road cause it is tiny tiny.
Its another job that is so easy even a girl can do it!
O and look at Pylos thread about speeding up his slow B engine with some porting - there is hope for the slower castings with a little work.
Cathy you are coming into this as a peak in moby stuff is going on, its a real MobyPlosion right now, there is TONS of info in here about moby superformance, it'll blow your mind how sexy these engines are, yes I said the engine is sexy, its so simple, not all barbaric like a sachs engine or a puch, Its just a crank shaft and a case, so simple, variators are super sexy too, and condensers from chevy nova's work perfect when the original fails, and thats all i have to say about that. Im going to the scrap yard......
crackstar
What are you talking about? chains do break. Especially old rusted ones that are over 25 years old.
Just look for a 415 chain with 122 links. Then you need to use a chain breaker and shorten it to the length of your old chain.
i think having the entire drivetrain hanging out in the open, several inches from your pant leg is barbaric.
mobys are sexy, but they certainly aren't more eloquently engineerd than the germans.
i keep looking for these letters people are talking about that designate speed. A, B, or C. Where are they located, front fork? that little plackard just says motobecane 50v, vin number, and no letters. dont say nothing on it but that. no letters. anyone know whats up? and you'd better mean barbaric in a good way.
It should say "50V A"
or B or C.
It was thought that pre-1980 A's were fast and post 1980 C's were fast. There are some examples of this being false.
French bikes are very eloquently designed and engineered.
i looked closer and im confused.... upon examination it actually just said "1976 50_" there's a little box where something is supposed to be stamped into, but nothing got stamped. It should at least say "50v" there cause i have the variator. dunno. guess i'll look at the ports next time i open the header.
-Steve
max speed on a moby i have experianced is around 55mph, and accelleration that will literally pull wheelies and throw u off the back if ur not ready, unvariated is a lower class of ped in my book.
have to agree. man... 55mph. i long for the day. tryin to get my shit together so everything is like clockwork before i expand.
You or the seller should have verified the speed by taken it for a test ride first, don't believe what they tell you.
I think bret is going over 55 now.
His bikes is officially more expensive then any car i've owned though.
Yo Steve... My 50V I.D. plate doesn'tt say A B or C either, I think it's a canadian thing
I've seen badges without a stamp before.
don't believe the badge, my travler says nothing but it goes 40 (well i swapped the motor) but if i sold it to somone i'd never tell em i swapped the motor i'd just be like "here this ped goes fast $600 plz" (going rate of well runnning mopeds in sf)
points!!!!
I found an av10 for sale. will these engines bolt right up to the av7 frame? Do they run as well? Same parts? Same ports? Same electrical? Basically, what would I have to do to put an av10 on my bike, a 76 50v av7? My engine is not the greatest, and if i can switch em up and be better off i'd like to. Thanks,
-Steve
it bolts up to the regular 50v frame. it runs a little quicker than a stock fast AV7. to put it on your bike, you would have to reuse your 6v stator plate and flywheel from your AV7, or wire up the stator plate from the AV10 to your existing setup. this will differ depending whether or not the AV10 has CDI.
almost all parts are totally different btw.
wire up the av10 to my existing setup.. im not that familiar with the wiring on my av7, but from what i can remember there are only 2 wires (plus a ground probably) going in/out of the flywheel, arent there? would i basically just unplug the wires, take off the av7, put on the av10, and plug em back in when i put the av10 on? av10 came stock with CDI? damn, pretty advanced for back then isnt it? i could reuse my flywheel and stator too, if i had to, cause its in decent shape.
older AV10s had points, which had a different stator plate than any of the AV7s in the states had. late '80s on up AV10's had CDI. if you wanted to just slap on your old stator plate and flywheel that would work fine. thats what i ended up doing...but my AV10 didnt have CDI. if the one you're considering buying does, i'd advise wiring it up (or selling it to me!)
haha alright. well i can probably put the av7 stator and flywheel on fairly easily. but what if i just wanted to keep the av10 stator (if it doesnt have cdi, which it probably doesnt). could i just "plug in" to the av10? or is it not that easy. granted, im on the 6v system with my 76er. thanks.
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