My Gilera CBA hates starting, and it hates me.

Hi, friends! I’m running into an issue with my Gilera CBA (aka Vespa Grande, kind of). It was great to start and ride all winter, but I’ve been chasing the problem all year and it seems to be getting worse.

She doesn’t want to start. Usually it takes a combination of me, my partner, and our friend taking turns pedaling to get her going, and usually it’s over the course of 10-20 minutes. Once upon a time, a hot start would be easy peasy, but now, both hot and cold are equally tiring and time consuming.

Here’s what we’ve got for a build:

43mm Malossi kit

Mazzi crank

Opened intake and intake patch

Sha 13.13 with Malossi air box

Malossi Multivar variator and matching x belt

Stock US rear pulley and clutch with new starter clutch shoes (yes, they’re on there right!)

New Kinetic CDI

Used to have a Malossi Too Bad, replaced with a Simonini Calibratta due to an air leak

The bike was hard to start when we bought it from Dos Cycles last year. Bike was listed as stock, but we found an Olympia 43mm kit and the Mazzi crank, as well as 13.13 Sha already installed. When we decided to put a new kit, we chose to go over the rest of the engine and make sure everything else was good…we don’t love surprises! We found that the flywheel had a huge gash. Couldn’t find a replacement for it at the time, as it is the external magnet one, so we chose to put the Kinetic CDI on it instead. We did not use the woodruff key after reading other Kinetic CDI conversions, and we followed Jason K’s thread about it. After all of that, it started easier than before, but still not as easy as all of our other Vespas. When you can get the bike started, it runs beautifully and can go up to about 50. Spark plug is a nice chocolate brown, not too rich or lean, and I’ve checked for more air leaks at the carburetor, exhaust, base of the cylinder, and head, and nothing. Not even the ~Vespa sauce~ around the exhaust header. We have a fat spark when it turns over. It feels like it needs just a little more oomph than what human legs can do. Sometimes pedaling fast works best, and sometimes pedaling slow works best, but there doesn’t seem to be any real consistency. Almost all of us Two Smokes have had and built great vespas, and not a one of us can figure this one out.

DD70B02A-4CCA-4DE9-BDBD-831039518885.jpeg

Re: My Gilera CBA hates starting, and it hates me.

Dirty30 Dillon /

My guess is on timing. Typically a too-retarded static timing will make cold starts nigh impossible.

What are you timed at?

Also checking and servicing the decomp is a great option as they can be eternally problematic.

Just a note, but most Vespa exhausts leak around the clamp unless you rework the split in the header and use a good clamp.

Re: My Gilera CBA hates starting, and it hates me.

Who drilled out the intake? Tried a different carb?

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Stephen Simmons wrote:

> -------------------------------------------------------

> Who drilled out the intake? Tried a different carb?

Jack opened the intake to ~13mm inner diameter intake and opened the intake duration to spec per the polini installation manual, which he’s done to 4 bikes. This didn’t affect the starting issue, as it was hard to start prior. The crank case did also pass a pressure test.

The bike has had 4 carbs on it, 3 of which were 13.13 Sha. All of them were installed on other bikes after, with no issue.

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Dirty30 Dillon wrote:

> -------------------------------------------------------

> My guess is on timing. Typically a too-retarded static timing will make

> cold starts nigh impossible.

>

> What are you timed at?

>

> Also checking and servicing the decomp is a great option as they can be

> eternally problematic.

>

> Just a note, but most Vespa exhausts leak around the clamp unless you

> rework the split in the header and use a good clamp.

When the kit was installed, we installed a new decomp and lapped it to the new head, and has passed a leak test with no leaks.

We set our timing to 1.5btdc when we installed the CDI, but before that it was just the stock points set with the woodruff key with the points set at .4mm.

This bike does not have the exhaust clamp leak as it has been sealed using hi-temp permatex per our usual build.

Re: My Gilera CBA hates starting, and it hates me.

> Jessi Linton wrote:

> -------------------------------------------------------

> > Dirty30 Dillon wrote:

>

> > -------------------------------------------------------

>

> > My guess is on timing. Typically a too-retarded static timing will

> make

>

> > cold starts nigh impossible.

>

> >

>

> > What are you timed at?

>

> >

>

> > Also checking and servicing the decomp is a great option as they can

> be

>

> > eternally problematic.

>

> >

>

> > Just a note, but most Vespa exhausts leak around the clamp unless you

>

> > rework the split in the header and use a good clamp.

>

> When the kit was installed, we installed a new decomp and lapped it to

> the new head, and has passed a leak test with no leaks.

>

> We set our timing to 1.5btdc when we installed the CDI, but before that

> it was just the stock points set with the woodruff key with the points

> set at .4mm.

>

> This bike does not have the exhaust clamp leak as it has been sealed

> using hi-temp permatex per our usual build.

Was it hard to start with the points?

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Stephen Simmons wrote:

> -------------------------------------------------------

> > Jessi Linton wrote:

>

> > -------------------------------------------------------

>

> > > Dirty30 Dillon wrote:

>

> >

>

> > > -------------------------------------------------------

>

> >

>

> > > My guess is on timing. Typically a too-retarded static timing will

>

> > make

>

> >

>

> > > cold starts nigh impossible.

>

> >

>

> > >

>

> >

>

> > > What are you timed at?

>

> >

>

> > >

>

> >

>

> > > Also checking and servicing the decomp is a great option as they can

>

> > be

>

> >

>

> > > eternally problematic.

>

> >

>

> > >

>

> >

>

> > > Just a note, but most Vespa exhausts leak around the clamp unless

> you

>

> >

>

> > > rework the split in the header and use a good clamp.

>

> >

>

> > When the kit was installed, we installed a new decomp and lapped it to

>

> > the new head, and has passed a leak test with no leaks.

>

> >

>

> > We set our timing to 1.5btdc when we installed the CDI, but before

> that

>

> > it was just the stock points set with the woodruff key with the points

>

> > set at .4mm.

>

> >

>

> > This bike does not have the exhaust clamp leak as it has been sealed

>

> > using hi-temp permatex per our usual build.

>

> Was it hard to start with the points?

Yes. When testing spark with the points ignition, it was intermittent. The flywheel magnet had a huge scar all the way around, about 1mm deep.

Re: My Gilera CBA hates starting, and it hates me.

> Jessi Linton wrote:

> -------------------------------------------------------

> > Stephen Simmons wrote:

>

> > -------------------------------------------------------

>

> > > Jessi Linton wrote:

>

> >

>

> > > -------------------------------------------------------

>

> >

>

> > > > Dirty30 Dillon wrote:

>

> >

>

> > >

>

> >

>

> > > > -------------------------------------------------------

>

> >

>

> > >

>

> >

>

> > > > My guess is on timing. Typically a too-retarded static timing will

>

> >

>

> > > make

>

> >

>

> > >

>

> >

>

> > > > cold starts nigh impossible.

>

> >

>

> > >

>

> >

>

> > > >

>

> >

>

> > >

>

> >

>

> > > > What are you timed at?

>

> >

>

> > >

>

> >

>

> > > >

>

> >

>

> > >

>

> >

>

> > > > Also checking and servicing the decomp is a great option as they

> can

>

> >

>

> > > be

>

> >

>

> > >

>

> >

>

> > > > eternally problematic.

>

> >

>

> > >

>

> >

>

> > > >

>

> >

>

> > >

>

> >

>

> > > > Just a note, but most Vespa exhausts leak around the clamp unless

>

> > you

>

> >

>

> > >

>

> >

>

> > > > rework the split in the header and use a good clamp.

>

> >

>

> > >

>

> >

>

> > > When the kit was installed, we installed a new decomp and lapped it

> to

>

> >

>

> > > the new head, and has passed a leak test with no leaks.

>

> >

>

> > >

>

> >

>

> > > We set our timing to 1.5btdc when we installed the CDI, but before

>

> > that

>

> >

>

> > > it was just the stock points set with the woodruff key with the

> points

>

> >

>

> > > set at .4mm.

>

> >

>

> > >

>

> >

>

> > > This bike does not have the exhaust clamp leak as it has been sealed

>

> >

>

> > > using hi-temp permatex per our usual build.

>

> >

>

> > Was it hard to start with the points?

>

> Yes. When testing spark with the points ignition, it was intermittent.

> The flywheel magnet had a huge scar all the way around, about 1mm deep.

New crank bearings and seal was installed?

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

>

> > > Was it hard to start with the points?

>

> >

>

> > Yes. When testing spark with the points ignition, it was intermittent.

>

> > The flywheel magnet had a huge scar all the way around, about 1mm

> deep.

>

> New crank bearings and seal was installed?

Yes, we did a fresh rebuild. Upon inspection a year down the road, we’ve found no oil leakage around the crank seal.

Re: My Gilera CBA hates starting, and it hates me.

> Jessi Linton wrote:

> -------------------------------------------------------

> >

>

> > > > Was it hard to start with the points?

>

> >

>

> > >

>

> >

>

> > > Yes. When testing spark with the points ignition, it was

> intermittent.

>

> >

>

> > > The flywheel magnet had a huge scar all the way around, about 1mm

>

> > deep.

>

> >

>

> > New crank bearings and seal was installed?

>

> Yes, we did a fresh rebuild. Upon inspection a year down the road, we’ve

> found no oil leakage around the crank seal.

Hook up a timing light and try to start the bike on the stand. I've seen them drop fire right where it would normally fire up. If the timing light stops flashing while you're trying to start it you need to go through the ignition/wires

Re: My Gilera CBA hates starting, and it hates me.

> Hook up a timing light and try to start the bike on the stand. I've seen

> them drop fire right where it would normally fire up. If the timing

> light stops flashing while you're trying to start it you need to go

> through the ignition/wires

We'll try that this anyways. I'd try it sooner but we're helping our prospect rebuild his kinetic. And update you on it! I want to get the wiring cleaned up on it a bit anways (its got a few wires that are a bit long and still needs a killswitch).

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Jack Linton wrote:

> -------------------------------------------------------

> > Hook up a timing light and try to start the bike on the stand. I've

> seen

>

> > them drop fire right where it would normally fire up. If the timing

>

> > light stops flashing while you're trying to start it you need to go

>

> > through the ignition/wires

>

> We'll try that this anyways. I'd try it sooner but we're helping our

> prospect rebuild his kinetic. And update you on it! I want to get the

> wiring cleaned up on it a bit anways (its got a few wires that are a bit

> long and still needs a killswitch).

Yeah, that.

Re: My Gilera CBA hates starting, and it hates me.

For whatever reason, I've found vespa wiring to be super brittle and unreliable. It could well be something as simple as a wire shorting out to frame somewhere.

Re: My Gilera CBA hates starting, and it hates me.

> Brian F wrote:

> -------------------------------------------------------

> For whatever reason, I've found vespa wiring to be super brittle and

> unreliable. It could well be something as simple as a wire shorting out

> to frame somewhere.

Yup

Re: My Gilera CBA hates starting, and it hates me.

> Brian F wrote:

> -------------------------------------------------------

> For whatever reason, I've found vespa wiring to be super brittle and

> unreliable. It could well be something as simple as a wire shorting out

> to frame somewhere.

The only original wiring on this bike is for the lighting. I learned the hard way about vespa wiring on a ride home from work in the dark on my si haha

Re: My Gilera CBA hates starting, and it hates me.

Dirty30 Dillon /

Just an info request:

You're running new starter shoes: are they the Olympia replacements?

You mentioned your running the matching X belt: is it the Malossi belt or the Gates X Belt? If it's gates which one?

I only ask these because I've never had good luck with the olympia replacement starter pads unless you REALLY shape them to match the bell. This can cause no start slipping. Additionally, the Gates AX series belt are particularly awful for starting on Vespas, as they are just barely to thin and tall for the aftermarket variators that they too can slip really easily.

Re: My Gilera CBA hates starting, and it hates me.

Have you tried a new/different ht coil.

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Dirty30 Dillon wrote:

> -------------------------------------------------------

> Just an info request:

>

> You're running new starter shoes: are they the Olympia replacements?

>

> You mentioned your running the matching X belt: is it the Malossi belt

> or the Gates X Belt? If it's gates which one?

>

> I only ask these because I've never had good luck with the olympia

> replacement starter pads unless you REALLY shape them to match the bell.

> This can cause no start slipping. Additionally, the Gates AX series belt

> are particularly awful for starting on Vespas, as they are just barely

> to thin and tall for the aftermarket variators that they too can slip

> really easily.

Starter shoes are Olympia…maybe that’s something to look into. I know it was hard to start before we replaced them, and the starter shoes were relatively new then as well.

The belt is the Malossi one. We tried other belts and they tore apart with the amount of force on the pulleys. This has been the only one that has worked lol

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> - Joe - wrote:

> -------------------------------------------------------

> Have you tried a new/different ht coil.

Yes, we changed it when we swapped to Kinetic CDI.

Re: My Gilera CBA hates starting, and it hates me.

Dirty30 Dillon /

> Jessi Linton wrote:

> -------------------------------------------------------

> Starter shoes are Olympia…maybe that’s something to look into. I know it

> was hard to start before we replaced them, and the starter shoes were

> relatively new then as well.

>

> The belt is the Malossi one. We tried other belts and they tore apart

> with the amount of force on the pulleys. This has been the only one that

> has worked lol

I would swap in a set of stock shoes (or really just a stock bell would be easiest) and see if that improves anything. No use doing hand-work if that's not the actualy problem.

Interesting you were shredding gates belts, which really shouldn't be an issue. The last time I had that issue was with the belt popping out of the rear sheaves and getting chewed by the clutch bell.

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> I would swap in a set of stock shoes (or really just a stock bell would

> be easiest) and see if that improves anything. No use doing hand-work if

> that's not the actualy problem.

>

> Interesting you were shredding gates belts, which really shouldn't be an

> issue. The last time I had that issue was with the belt popping out of

> the rear sheaves and getting chewed by the clutch bell.

I think that would be worth trying. I haven’t swapped the clutch at all aside from the shoes, and I want to eventually put a performance clutch on it after I track down this issue.

I don’t think I’ve used the gates belt, I tried other recommended belts based on the guide I used (a couple of which were like lawnmower belts), and I actually had a little trouble with an early Malossi x belt, before they updated it.

Re: My Gilera CBA hates starting, and it hates me.

If you have a good drill see if it'll start with it. If it does you definitely have clutch/belt issues

Re: My Gilera CBA hates starting, and it hates me.

> Stephen Simmons wrote:

> -------------------------------------------------------

> If you have a good drill see if it'll start with it. If it does you

> definitely have clutch/belt issues

Yup, this is what I was going to say. Or even wrap a strap around the variator. All of the hard starting vespers I've had have been belt/starter clutch bullshit, just not quite enough torque to get a nice sturdy pop.

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Graham Motzing wrote:

> -------------------------------------------------------

> > Stephen Simmons wrote:

>

> > -------------------------------------------------------

>

> > If you have a good drill see if it'll start with it. If it does you

>

> > definitely have clutch/belt issues

>

> Yup, this is what I was going to say. Or even wrap a strap around the

> variator. All of the hard starting vespers I've had have been

> belt/starter clutch bullshit, just not quite enough torque to get a nice

> sturdy pop.

Thanks, guys. I’ll try it out. Because I’ve consistently had issues, even with all the changes I’ve made, I was almost leaning to a crank case issue because that’s the constant, like the one thing I haven’t changed. I just don’t know what about that would have even been the issue.

Re: My Gilera CBA hates starting, and it hates me.

Dirty30 Dillon /

If you've done a proper leak down test and you are holding 5psi with very little drop-off, than the only thing that would inhibit starting that I can think of would be an over-sized intake patch. If it dosn't have enough of a lip to seal, it may be incredibly hard to start.

But given that you stated it's always been hard to start, and that hot/cold no longer matters, I am leaning towards start mech issues.

Re: My Gilera CBA hates starting, and it hates me.

" kinetic cdi". Did you use kinetic coils under the flywheel..which flywheel. OEM kinetic cdi unit ?

I'm assuming it's timing. I pretty much have the exact same parts ( or so I think) on my grande. I'm using kinetic coils, the flywheel with the white plastic fan . I have a bunch of OEM kinetic cdi s but instead I use a parma one wire with a curve.

I found the kinetic cdi unit to be entirely unreliable, that why I switched to the Parma. The "correct " placement of the flywheel without the woodruff ( it's way away from the spot where the keyway alligns ) to be because I couldn't pinpoint where the location of the "trigger" is on the flywheel. I ended up marking the case and the flywheel at TDC and using a degree wheel marking about 16degrees before TDC. Then with the engine installed get it running with a drill start. And see where the timing marks allign. It's possible, though unpleasant, to actually lift the flywheel and reset it and recheck but I will cause you to pull your hair out if you have any.

Re: My Gilera CBA hates starting, and it hates me.

> Marc Friedman wrote:

> -------------------------------------------------------

> " kinetic cdi". Did you use kinetic coils under the flywheel..which

> flywheel. OEM kinetic cdi unit ?

>

> I'm assuming it's timing. I pretty much have the exact same parts ( or

> so I think) on my grande. I'm using kinetic coils, the flywheel with the

> white plastic fan . I have a bunch of OEM kinetic cdi s but instead I

> use a parma one wire with a curve.

>

> I found the kinetic cdi unit to be entirely unreliable, that why I

> switched to the Parma. The "correct " placement of the flywheel without

> the woodruff ( it's way away from the spot where the keyway alligns ) to

> be because I couldn't pinpoint where the location of the "trigger" is on

> the flywheel. I ended up marking the case and the flywheel at TDC and

> using a degree wheel marking about 16degrees before TDC. Then with the

> engine installed get it running with a drill start. And see where the

> timing marks allign. It's possible, though unpleasant, to actually lift

> the flywheel and reset it and recheck but I will cause you to pull your

> hair out if you have any.

The the white plastic fan kinetic dealeo. We've set the timing with the motor still in the bike. With marking the fly wheel and fan shroud and using a timing light Total nightmare haha. I wouldn't doubt the kinetic cdi box is garbage haha

Re: My Gilera CBA hates starting, and it hates me.

> Dirty30 Dillon wrote:

> -------------------------------------------------------

> If you've done a proper leak down test and you are holding 5psi with

> very little drop-off, than the only thing that would inhibit starting

> that I can think of would be an over-sized intake patch. If it dosn't

> have enough of a lip to seal, it may be incredibly hard to start.

>

> But given that you stated it's always been hard to start, and that

> hot/cold no longer matters, I am leaning towards start mech issues.

The intake patch is widened but is much narrower than any other bike I have done. Ive also be pondering the thought of maybe there is an issue with the cases. Maybe they are haunted.

Re: My Gilera CBA hates starting, and it hates me.

Jessi Linton /

> Stephen Simmons wrote:

> -------------------------------------------------------

> If you have a good drill see if it'll start with it. If it does you

> definitely have clutch/belt issues

We tried, and it starts like a dream! We took apart the clutch bell and there was slippage but I checked the starter shoes like someone else suggested, and it’s clear that they aren’t quite the right shape. I want to try a wider belt, but I definitely need to do something with the clutch. The whole thing was pretty glassy, so that’s getting an update. For now, I can drill start it, and we even rigged an emergency tape and wire pull start that works well for the time being! Thanks everyone for the suggestions! Sometimes it takes an outside brain or five.

Re: My Gilera CBA hates starting, and it hates me.

Nice!

I don't know how to fix the aftermarket shoe issue, when it happened to me it was the posts that they pivot on were rusty and I just took it apart and lubed it up.

Be careful starting it with a drill all the time, that 8mm thread on the end of the crank will snap off if you beat on it too bad.

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