Piaggio Skipper Running Poorly?!

Hey guys... A few months ago, I found a 2nd hand Piaggio Skipper 125 to buy for work. I went to the sellers and test drove the bike before purchasing it. It ran fine!!! On the way home I opened up the throttle to see what it could get up to and it easily hit 60-65mph.

I left it alone for a few days to get insured, etc. Then one morning, went to go to work and the throttle started bogging down when initially opening it up, eventually not starting/sparking at all!

I left it with a so-called piaggio specialist garage and they tried to charge me £120, even though they couldn't find the problem, @#*!'s! Then sent it to a sparky garage an' the gaffa says I need a new CDI?

Piaggio Skipper's have an immobilizer system and the CDI handles this, so getting a new CDI is not so straight forward! I found a seller on e-bay that had custom made CDI's for £80 that bypass the immobilizer, so I bought one and fitted it.

It done it's job and bypassed the immobilizer, I even got a spark back and managed to start the bike up, thing is... Now it's running again but it's running like a restricted 50cc! The throttle is almost completely unresponsive!

I cleaned the carb/jets, checked the vacuum/fuel lines/diaphragm, air filter, belt, changed the plug and fully charged the battery. Though the bike is running "finer", it's still "restricted"!

When taking off the bike seems to have to hit a certain RPM before there is noticeable acceleration from the CVT. This can take a few seconds and it struggles to get moving no matter how wide the throttle is open?! Even pulling out on small inclines, it will struggle to "get going" and sometimes won't at all?!?

My initial reaction was to query the new CDI. It was "compatible" and the seller said it was not restricted and even sent out a replacement which responded the same as the first one.

Personally I am thinking about replacing the CDI with one from another Skipper @ £130, as this is really the only change since it hit 65mph! I've checked online for the immobilizer "flash code" and it tells me that a 0.7sec single flash then off, means that the immobilizer is working fine and that is what I get when I re-install the original CDI, yet no spark from it???

Thx-a-mil

 

could be that a roller has jumped out the channel and gone sideways

 

Pump jet and or hole in the diaphram?

 

Sounds viable, will check!

 

Sorry dude, am fairly new to scoot's 'n don't know what the "Pump Jet" is?

Only diaphragm tested was fuel tank, removed fuel line from carb 'n started it up, fuel flowed as expected!

 

Have been reading up on "belt slippage" and have to say that this feels like what I'm getting when starting off. only thing is: I heard a metal rattle from the CVT, worked out it was the bendix/starter, but pinch-checked the belt whilst cover was off 'n it was pretty damn torque. Tried to test it with the CVT cover off whilst running 'n apparently can't due insecure starter or something? So haven't really seen the CVT in action.

 

Anyone have any ideas about CDI spark timing? Could the newly installed CDI be out of sync? Don't know much 'bout timing myself, but read that the ? stator plate ? can be adjusted to adjust the spark timing?

 

The stator can't be adjusted, the diaphram is in the top of the carb, have a look for holes or hardness of the rubber.

 

Cheers dude didn't think about that diaphragm, newbie! Will check when re-clean carb 2moro...

P.S. Asked 'bout stator due to reading: "The stator plate has elongated screw slots so it can rotate by about 10 degrees while remaining connected to the crankcase (blue arrow). These allow the timing to be adjusted by moving the relationship of the pick-up (pink arrow) to the flywheel/piston position."

 

I'm 99% sure the stator is fixed with no adjustment! I stand to be corrected though!!

 

No worries! You know more than i... Took the carb apart today 'n think the diaphragm spring was in a bad position, so re-placed it. Started it up an' think I got a bit a dust in it as only made things worse, can't be ^$$£) tonight try again tomorrow!

Am however getting some real bad "juddering"/vibration from the rear end that lasts till it gets to a certain rev count then it smoothens right out and the rev's rocket up, which lends credence to what "Stevep" mentioned about the rollers?!?!?

Logically I'd assume that if 1 roller was stuck toward the center and the others were toward the outer rim that that would cause such violent vibration, until at a certain rev the stuck roller was dragged to the outer rim, cancelling out the vibration?

 

Not really; what a stuck or jumped roller does is effectively keep the scooter in high gear, so that it has to build up speed for it to accommodate the position that the variator is stuck in. If you can understand what I mean.
The cause of a stuck roller is either it's worn out, too small for the variator, or the ramp sides are worn out.

 

Can understand that! Thx Ste I had it the wrong way round. Thing is, I haven't quite got to checking the rollers yet. I blocked off the carb's "breather pipe", I think it's called, by chance the other day and the torque from the bike increased dramatically! This is leading me to believe that I have air/pressure/gasket leak somewhere. Am currently going round all seals with WD40

 

First of all... What's there to like SliderTom?

Second... Big up to Stevep, he called it... Jammed roller:



This one's weight had slipped it's plastic jacket and worn it's way into the ramp wall, wedging it in place!

On closer inspection all ramp walls were severely worn and a few of the rollers were beginning to flatten out. As a temporary fix I removed the problem weight from it's jacket, flipped it over and re-inserted it back into it's jacket. After re-assembling the bike, I got a fair bit more torque out of the back wheel! New variator/rollers asap...

Thanks to MARSH and especially Stevep for all their help! Sad to say this is only one problem down tho, in that I've still got issues with the carb that I'll try to consolidate into a new thread...

 

That roller will slip its jacket again quite soon. Shouldn't be able to take it out. Got any lying around that can replace it? One of your mates maybe?

 

Sadly Ste I don't run in them circles, just bought a bike for work Don't expect it to stay where it is, just a temp fix till I order the new ones tonight/tomorrow. Am a bit f**kd tho as there's no markings on the rollers and I don't have a set of digi scales to hand! One pdf on factory rollers says, size: 19x17, weight: 12.3... As I've never done this before I've no comparison, this sound reasonable to you?

 

19 x 17 12.5 for the 2 stroke 125 engine
19 x 17 8.6 on the 4 stroke 125 engine

 

8.6 it is! Thx. Am writing the carb thread as we speak, would appreciate any input you have, will post link here when it's done.

 

carb thread