vespa help needed

ok ... my vespa grande is down for a bit. here's the scoop ... maybe you vespistas or others can help me out ... i'm new to this type of moped design.

the decompression cable just pooped out on me. luckily, daveb (moped army member) was kind enough to manually hold the decompression down for me while i push started the bike ... so i was able to ride it home. but i can't get it to start on my own ... so repair is in order.

the cable went limp as i started it ... and i'm sure it came out from the engine end. as i traced the wire back, i pulled on it (not too hard), and it came out. also, a small rubber snap of some sort fell out (i still have it). i'm not sure how bad the cable problem is. the cable end does not have a nub so i'm not sure what it would "hook" onto.

how do i fix this? where does the cable go? i will try to get it all working together saturday if possible. luckily my trusty lucia is still up and running like a champ (and i'm sure jealous and rearing to go).

so i'm looking for help on fixing my vespa. any help would be appreciated. i think some motobecane people can help ... i'm all ears.

Re: vespa help needed

Miguel,

The decompression cable is only necessary to kill the engine. It makes it easier when roll starting it, but isn't really necessary. So, you can ride the bike while you figure out how to fix.

Here's what you need to do. The cable comes into the cylinder head fins from under the gas tank. There is a slot in the cylinder head fins where it goes through. Then, the ball on the end of the cable hooks through the hook on the end of the decompression lever. Because it comes in from that side, when you pull on the cable, it pulls the lever down toward the cylinder. If this description is inadequate, let me know and I'll try to get a picture together this weekend of what it is supposed to look like.

Chris S (vespista)

Re: vespa help needed

The engine end of the decompression cable should have a barrel connector on it that is perpendicular to the cable. This must have come off at some in the past and someone jury rigged to work. The rubber thing that fell off isn't part of the original cable end .

See if you can a find a barrel end that has a hole and a set screw so you can slide it on the loose cable end and tighten it down, The barrel connector hooks over the decompression lever by the spark plug. The cable sheath should end at the notch in the top engine shroud so it can press against the plastic shrould when you pull the decompression lever.

Try a local hardware store or bike shop.. You can order a new cable from the Super shop at 619-574-1818. They are closed on Saturdays - Mondays.

Good luck

Re: vespa help needed

ok, neither descriptions makes sense to me. i also tried roll starting the bike, but to no avail. maybe i have to try harder? i'll see if that does it ...

so ... does the cable at the engine end need a nub or something? mine does not. and do i somehow slide cable in first through the head from the sparkplug end? i don't remember a cable there ... but maybe i just didn't pay close attention.

if it goes in another way ... do i have to disasemble some part of the bike? the cable is now out of the bundle of other cables (brake, throttle) and just hanging down. it's a clean-end cable (no nub or anything that would "catch" or "hook" on anything).

argh! i don't want this to be a huge pain in the ass problem!

Re: vespa help needed

Don't worry Miguel, this is a simple problem to fix. To answer your first question, yes, the cable needs a nub, so get yourself a new inner clutch cable. Next, look at the front of the engine. To the right of the spark plug, there should be a piece of metal that looks kinda like a hook on one end, and the round end of a safety pin on the other. It runs up and down, from the top right cylinder head nut to the bottom cylinder nut. In the middle it is secured with a clamp like deal. (It sounds like yours is missing.) You dont have to disassemble anything to get the cable back into the working position...that piece of metal is like a spring, and you just push the hook-like end in with a screwdriver enough to slip the cable back in.

Hope this helps!

Re: vespa help needed

The way I reassemble this cable is I slip it through the hook so that the barrel-shaped nub is toward the front and the cable is heading back. I then pull on the cable housing backward toward the crankcase. This pulls the spring loaded decompression lever down and gives enough free cable to seat the cable housing in the slot on the top of the cylinder head. When properly installed, the outer cable housing comes in from the crankcase end of the cylinder head. It fits into the groove between two fins. The inner cable continues forward to the lever and is secured in the hook.

Miguel, if this is still confusing, I'll try to locate a picture this weekend and post it. It is a piece of cake to install. No tools or disassembly required.

Chris

About decompression and roll starting

Miguel,

The Vespa owner's manual only mentions the decompression lever in two ways: it is used to kill the engine, and it is used to assist in roll starting. You simply pull it to kill the engine. When starting, you can (not necessary, however) hold it down until you get going, then let it go and the engine will kick over. I never seem to need it this way on any of my Vespa mopeds. To roll start, simply start pedaling and it will eventually kick over as the clutch starter shoes grab and the belt turns the variator and flywheel. If it is not grabbing (assuming the starter shoes in the clutch are working properly...when the springs get old they get brittle and break, but they are easily replaceable...I have extras), then either the variator needs new grease on the rollers, or the belt is worn out. If the variator is turning and the belt is grabbing, then it should start (assuming you have spark, compression, and fuel).

Chris

Re: About decompression and roll starting

ok ... still confusing ... but i'll try roll starting today ... maybe i can still get everything to work ok ... but i've been riding my snark (so fast!) ... if you can find a pic, hook me up. i'm totally lost on what you mean. maybe just lack of sleep?

Re: About decompression and roll starting

Ron Brown /

Miguel,

The description of the decomp valve sounds about the same as a Motobecane. If it is not obvious from looking at the valve opening mechanism, maybe you have lost some other part of it. You did mention that someone operated the valve manually for you so I think you must at least have the operating lever. The cable (with a barrel end), should slip into a fork on the end of this lever, then all you have to find is where the outer part of the cable is supposed to live so that it does not move.

On pedal starting w/o a decompressor, I have never succeeded on my model 7s.

My theory is that as you get up to clutch engagement speed, the drag on the clutch is enough to keep you from pedaling fast enough for the clutch to fully engage so you just generate heat (and sweat).

Maybe Chris is bigger, or at least more energetic than us. : )

Ron

Re: About decompression and roll starting

Energetic? Probably not...Larger? 205 lbs... Perhaps the other bikes don't start as easily? With the exception of one Grande (which has some belt slip once in awhile), I don't seem to have trouble just pedaling and going. In fact, the vespa owner's manual describes starting as just putting one foot on a pedal while standing next to the bike and kicking it like a motorcycle. I could only ever make this happen on a Ciao I used to own that was geared lower. Unfortunately, I don't own any other brands to compare.

Chris

P.S. I do sometimes work up a sweat...:)

Re: About decompression and roll starting

Ron Brown /

Chris,

The Motobecane manual describes this method of starting too, in fact they tell you never to pedal on the center stand (which I do most of the time for a cold engine). The difference is that they tell you to use the decomp as well. Push on the pedal, let go of decomp when the engine turns, let go of choke when engine starts. All before the pedal hits bottom. I think I have managed this once, on a warmed up engine.

135 lbs and no sweat. : )

Ron

Re: About decompression and roll starting

my center stand is broken, so i can't start on the stand. i also weight about 130lbs ... so my weight/force isn't enough (apparently) to get it to start.

the problem i have in understand how to put the cable in. i think it broke. the cable is barren on the engine end ... and i think i'm supposed to slide it through the engine (??) so that i comes out from the spark plug end (i'm not supposed to put in from that end, am i??). but i just haven't messed w/ it enough yet, i guess.

the cable originally seemed to go down into the box area (it was bundled w/ the other cables). so i think i might have to open up the side panels and get into it that way.

i'd still ride it ... but i can bend down and hold the decompression manually as i try to push the bike. it's just not practical.

if someone can post a pic (i'm sort of a visual person, i guess) of how the cable goes in ... that would be great. i think i'll have to order a cable (??) and get the whole thing redone (??).

Re: vespa help needed

Ron Brown /

Miguel,

read Chris' post again. It is so clear I can see it in my head. Your cable may still be ok if it is long enough, you just need a screw clamp barrel nipple for the end.

Ron

Re: About decompression and roll starting

Miguel,

I'll take a picture if you need it, but I made a quick drawing. It is attached. See if it helps. It is from the top view.

Chris

decomp.jpg

Vespa Parts for Miguel and Vespalad

Miguel,

I found my extra centerstand. It has been repaired, however. Email if you are interested. I can probably also get you the filter screen you need.

Vespalad,

I called my buddy about the key. He is willing to sell. Let me know if you want it.

What were the other things you two needed?

Chris

Re: Vespa Parts for Miguel and Vespalad

Chris,

I still want that key. Thank you for contacting your friend for me. Let me know a price and an address to send it to. It may be about a week before I have any extra cash, though. Sometimes I can be quite an idiot about spending money. Rent runs me $175, which just hapened to be the price I talked my friend down to for my new Bravo (originally he said $350, I don't know HOW I managed that one...). Having learned my lesson with those Yamahas, and rushed out to pick it up imedately, then realized an hour later that rent was due in 5 days. Then, we got a bill in the mail every day for the last 4 days. It kinda sucks, I'm hoping to make it up to Denver on the 13th for my favorite band, the Slackers, but I'm not sure if I'm going to have enough money to go. But things have a way of working out, so we will see.

Also, I'm looking for a spedometer and a carburettor for my 78 ciao.

Thanks Again!

Re: Vespa Parts for Miguel and Vespalad

yep, the drawing helps. i also looked at my vespa a bit more and realize that i somehow have to just slide that cable down through and out the spark plug end. so it makes sense. i'll see if i can get that done tomorrow (i have no time now). sorry, i've been a bit frazzled ... lack of sleep does that (work deadlines always crashing upon me).

since i don't have a nub on my cable, do you think the little cap on a sparkplug would work? (i could sauder it or something). or how to get it to stay put? any ideas?

Re: Vespa Parts for Miguel and Vespalad

oh, yea, the center stand and screen would be great. how much would you want for it, though? shipping included.

Picture worth a 1000 words

Picture worth a 1000 words

Grande_Decompression_cable_front_right_side.jpg

2 pics worth 2000 words?

Here tis

Grande_Decompression_Cable.jpg

Re: Vespa Parts for Miguel and Vespalad

solder wont hold ,but you can get cable stops at bike shops, they use a set screw

Re: Vespa Parts for Miguel and Vespalad

awesome! thanks guys.

Re: 2 pics worth 2000 words?

Hey,

My drawing wasn't too bad...I did it from memory while at work. Thanks for posting the photos Zippy, I don't have a digital camera and was going to have to take pics, develop and scan.

Chris

Re: 2 pics worth 2000 words?

i want to reiterate that i was thanking the pics and the drawing. all were awesome. i will probably post a lot as i learn the vespa design. i'm slowly realizing that it is almost nothing nothing at all like the minarelli. wow.

Re: Cable end

When my decompressor cable end popped off, I found a universal choke cable end(automotive) in my tool box that worked.

You can get these at an auto parts store. Look in the section that has those "HELP!" items in the red blister packs. Ask at the counter and they'll take you to it.

Works for me!

Jim

Re: 2 pics worth 2000 words?

Have you thought about getting the Haynes manual? Vespa supershop sells them for like 15-20 bucks, which will more than pay for itself in the time it will save you when working on your ped. I love mine!

Re: 2 pics worth 2000 words?

Hi Chris

Your drawing was great. I posted before I checked the previous postings.

I had a Grande on the bench I was getting ready for a top end overhaul so I just grabbed the Digital and took some shots. Right now I have three Grandes in the works and four Grande parts bikes. The Grande in the picture was a customers bike.

Re: 2 pics worth 2000 words?

oh yeah, when i get a chance i want to get a manual. i want to learn the vespa inside and out ... i'd like to see some more vespas in town running around all italian style.

note to Zippy and Miguel

Hey guys, now that I read your postings and re-read mine, I realize that you thought I was offended. I wasn't (even though my language seems to imply that I was). What I was attempting to communicate was, "hey, now that I see the actual photo, I can see that my memory of what it looks like wasn't far off." Unfortunately, it looks as though I wrote, "hey guys, why did you need to post a photo, my drawing was good enough." I guess paralanguage doesn't come through in written text as much as we would like.

Sorry for the confusion, and thanks for the photos, Zippy.

Chris

vespa runs again!

thanks all ... my vespa runs again. i cut the casing on the clutch/decompression cable so that i would have more length on it and finally (took many many tries) got it through that crazy hole and into the hook. i found a screw cable end ($0.99) and put that on. now i have a decompression lever!

i'll still have to mess w/ it to get it back to "normal" (i eventually want to restore my grande ot it's former glory ... before moding it out for speed).

thanks for all your help!

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