OP
UTC

Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
 
Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
UTC quote
Kinda slow at work and cruising MV, and got to thinking about a cylindar kit.

Got an 08' Stella that is mostly stock with about 20,000 miles on it.

It seems like every couple of years I come back around to the idea of a cylinder kit to get a little more umph out of the scoot.

Any recomendations on a kit? I was looking at the Pinasco 177 and the Polini 177.

But sitting here thinking about it I am starting to wonder a couple of things, like for instance, if I am going to do some invasive surgery on my engine like this should I go further and do a crankshaft?

I'm pretty sure that I've read on MV or heard somewhere that the crankshaft is a commen failure point on the Stella/lml. Which makes me wonder, what aspect of the crank fails? Are there indicators that its about to fail or it just goes and you'll never know until it happens.
@steely_dan avatar
UTC

Enthusiast
Lambretta GPs Lambretta S1s, Vespa Gl, Vespa P200, Serveta 150
Joined: UTC
Posts: 75
Location: United States
 
Enthusiast
@steely_dan avatar
Lambretta GPs Lambretta S1s, Vespa Gl, Vespa P200, Serveta 150
Joined: UTC
Posts: 75
Location: United States
UTC quote
You for sure need to replace that crank, I'm shocked it hasn't gone boom yet after that many miles. It will certainly go boom with the addition of a cylinder kit.
In my opinion the Polini and Penasco kits are a bit antiquated and expensive for what is currently available on the market. The VMC Stelvio is a great option as well and the kit from BGM. I recently built a Quattrini on a stella for a friend and it is blistering fast. There are so many options now you can really pick exactly what you desire.
Good luck with you build.
@mjrally avatar
UTC

Veni, Vidi, Posti
73 & 74 Rally, 76 ET3, 80 P200, 06 PX150, 59 Ser 2, 65 Silver Special, 90 V5N 50, 2015 HD Road Glide Special
Joined: UTC
Posts: 5142
Location: Oceanside, CA
 
Veni, Vidi, Posti
@mjrally avatar
73 & 74 Rally, 76 ET3, 80 P200, 06 PX150, 59 Ser 2, 65 Silver Special, 90 V5N 50, 2015 HD Road Glide Special
Joined: UTC
Posts: 5142
Location: Oceanside, CA
UTC quote
Sadly the only indicator you may get before the crank fails is a loud noise that sounds like bolts in a dryer. The big end bearing fails which wobbles the connecting rod/ throws bearing cage shrapnel in the motor.

Definitely worth replacing all the original bearings and a cut crank from a reputable company should be fine for a 177 kit.

Make sure whatever kit you buy says something along the lines of Electric start compatible!!
@orwell84 avatar
UTC

Ossessionato
Joined: UTC
Posts: 3199
Location: northern New York
 
Ossessionato
@orwell84 avatar
Joined: UTC
Posts: 3199
Location: northern New York
UTC quote
MJRally wrote:
Sadly the only indicator you may get before the crank fails is a loud noise that sounds like bolts in a dryer. The big end bearing fails which wobbles the connecting rod/ throws bearing cage shrapnel in the motor.

Definitely worth replacing all the original bearings and a cut crank from a reputable company should be fine for a 177 kit.

Make sure whatever kit you buy says something along the lines of Electric start compatible!!
When mine failed there was no warning and it was before I had time to shit my pants.

Not all Stella cranks had this problem, but I don't think they are up to pushing a kit. Do everything while you have the case open.
UTC

Hooked
Rat 2003 Stella 2T; 1979 P125x (in pieces, out for paint)
Joined: UTC
Posts: 384
Location: Madtown
 
Hooked
Rat 2003 Stella 2T; 1979 P125x (in pieces, out for paint)
Joined: UTC
Posts: 384
Location: Madtown
UTC quote
The Stella crank problem, as I understand it, was limited to a certain period of time when the workers were installing the main bearing wrong or something like that. But regardless, 20k is a good time to replace! Also bearings and seals. And of course shifting cross!

I have tried the polini, pinasco, and malossi kits on my Stella, and I have really grown to love the malossi. It's been super-durable, and has tons of power at high revs, despite being only 166cc, it's really a fun, shit-faced-giggles kind of thing when going around town, on highways, etc. even without any case-matching.
OP
UTC

Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
 
Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
UTC quote
Thanks for the good feedback.

Is there a date range for stellas produced with crank issues I wonder?

I had been mostly looking at the polini based off what was on scooterworks.com the write up says that its very reliable

Looking to set up for touring

Seems like a lot of the cyclinder kits are made of aluminum, besides good heat disipation are there any other pros or cons to aluminum?

I'm not worried about being compatable with electric start.... I deleated that a long time ago when it stopped working
@chandlerman avatar
UTC

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9935
Location: Nashville

70 Days Since Last Explosion
 
Lucky
@chandlerman avatar
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9935
Location: Nashville

70 Days Since Last Explosion
UTC quote
MJRally wrote:
Definitely worth replacing all the original bearings and a cut crank from a reputable company should be fine for a 177 kit.
Not a cut crank on a Stella. You want a flowed or bell crank.

What sort of riding are you doing? Different top ends have different power curves, so you should choose the one that will work for you.
@v_oodoo avatar
UTC

Style Maven
'74 50s x3 '87 PK125XL '92 PK50XLS Plurimatic - & - '58 AllState '68 Sprint '66(?) Super125 and '72 DanMotor Super150
Joined: UTC
Posts: 9618
Location: seattle/athens
 
Style Maven
@v_oodoo avatar
'74 50s x3 '87 PK125XL '92 PK50XLS Plurimatic - & - '58 AllState '68 Sprint '66(?) Super125 and '72 DanMotor Super150
Joined: UTC
Posts: 9618
Location: seattle/athens
UTC quote
TheWizard wrote:
...
Is there a date range for stellas produced with crank issues I wonder?
...
I believe there is. I recall Rob Hodge giving a detailed explanation of the problem involving too tight fit on bearings that then failed and wrecked the crank. I want to believe that cranks outside of that range are likely decent quality given how well the rest of the motor was made.

I should try to find the info - I run an LML in my Super... Do any of you LML experts know more, and how to date the motor from the serial number? I do drive my Super gently, but would like to know what I have.
The serial number is preceded by E16JR all on a single line.

This motor came installed in my 125 Super, I know nothing about it other than it runs well w/ lots of stock power except Sito+ and usually starts one kick - it has NEVER quit on the road.
The serial number is preceded by E16JR all on a single line. This motor came installed in my 125 Super, I know nothing about it other than it runs well w/ lots of stock power except Sito+ and usually starts one kick - it has NEVER quit on the road.
This motor is newer, came low miles from a new Stella about 2011 when it upgraded to P200. It has auto lube & electric start , let me know if you are looking for one.
This motor is newer, came low miles from a new Stella about 2011 when it upgraded to P200. It has auto lube & electric start , let me know if you are looking for one.
@chandlerman avatar
UTC

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9935
Location: Nashville

70 Days Since Last Explosion
 
Lucky
@chandlerman avatar
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9935
Location: Nashville

70 Days Since Last Explosion
UTC quote
It was only one or two batches of early (like 2003-2004) Stella's. At this point, I think they've all either grenaded, were repaired (replaced) under warranty, or off the road dead for some other reason.

It's been years since I heard of any cases in the wild.
UTC

Veni, Vidi, Posti
Joined: UTC
Posts: 7045
Location: Tega Cay, SC
 
Veni, Vidi, Posti
Joined: UTC
Posts: 7045
Location: Tega Cay, SC
UTC quote
I had heard of a few post-strike Stellas imploding, but you never know how the owners were treating them. I had a 2003 that had about 5k on it at purchase and I put another 13k miles on it before selling it off to get a P200. I do know the guy I sold it to thrashed the living hell out of it and it grenaded before it hit 20K.
OP
UTC

Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
 
Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
UTC quote
I've been digging around on MV and also the google about Stella crank issues

Was reading some stuff buy Rob Hodge about this very issue from 2014

for reference - Stella: A few performance questions

If he is right its a small percentage of Stellas that had this issue which is baised on the larger bearing being pressed to tight to allow for proper lubrication.

Baised off what I was reading they generally failed in the 5000 mile or less range, which to me would make sense if they werent being properly lubed.

VooDoo, it seems like there is no date range, but rather a quality issue.

I actually looked at my milage last night, its more like 16000 (sorry I was estimating before). It had less than a mile on it when I bought it so I know the bikes history.

I rather think that if the bearing were to fail it would have by now.

This actually makes me curious, if this were a vespa p150 with this milage would replacing the crank even be an issue?
[/url]
@kowalski avatar
UTC

Addicted
2005 Stellalossi 177 Fe
Joined: UTC
Posts: 519
Location: MA
 
Addicted
@kowalski avatar
2005 Stellalossi 177 Fe
Joined: UTC
Posts: 519
Location: MA
UTC quote
If you kit a Stella, you should replace the crankshaft as a matter of course.

The bad Stella crank problem is much more prevalent than this discussion suggests. Rob Hodge's posts were based on data from about 2010. Hundreds of cranks have failed since then. My 2005 failed 2 years ago. 245Luigi's 2005 failed last year. If you follow the Stella owner's group on Facebook, there is a steady stream of new failures reported. Even if your odds start out better with a 2008, a good kit will double the horsepower from stock. In that case, the risk goes off the charts.
Forum member supplied image with no explanatory text
@chandlerman avatar
UTC

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9935
Location: Nashville

70 Days Since Last Explosion
 
Lucky
@chandlerman avatar
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9935
Location: Nashville

70 Days Since Last Explosion
UTC quote
Kowalski wrote:
If you kit a Stella, you should replace the crankshaft as a matter of course.
I 100% agree with this.

If the Stella cranks' original design specs assumed 4.9HP, then as soon as the motor goes over that, the service life will begin to fall, eventually exponentially. Hence the need to upgrade when upgrading the top end (also, it's not designed for performance, so you might as well Razz emoticon ).

However, I would question the "hundreds" estimate being due to the quality issue. Not to say that hundreds of cranks haven't failed, just that manufacturing quality issue was a relatively small portion of the overall number of Stellas built and it was identified, documented, and remediated at the time.

There's the weird desire to assume that *any* Stella crank failure was a result of those two bad batches, which is simply not the case. Which is also not to say that Stella cranks don't have other design and manufacturing quality issues, but they have not been categorized and tracked with the same level of rigor.

Now back to crankshafts and quality vs. design issues...

If we assume the OG Stella crank has a shorter expected service life than a P-series crank (I'm assuming stock cranks throughout this), then that's a different issue (design failure, underestimating service life, probably in the name of cost reduction) than the big end bearing manufacturing quality issue. Conflating two different failure modes only muddies the water.

Lastly, a failed little end bearing has nothing to do with the original quality issue, which was on the other end of the conn rod. Mud. water. again.

When discussing failures, you have to break down and classify the failure modes by root cause. You analyze them separately to then come up with an overall Mean Time Between Failure (MBTF). Anything else is just backing into the pre-determined conclusion.
@orwell84 avatar
UTC

Ossessionato
Joined: UTC
Posts: 3199
Location: northern New York
 
Ossessionato
@orwell84 avatar
Joined: UTC
Posts: 3199
Location: northern New York
UTC quote
My crank failure occurred on a 2008. I have heard many references to failure and general poor quality of Stella cranks. If you had a high mileage stock engine with a Piaggio crank, it would still make sense to replace or at least evaluate the crank if adding a kit. Cranks can be rebuilt, but it seems to be cheaper to replace them, at least with Vespas.

Stella/LML bearings are also mentioned as being lower quality, but you would probably be replacing those too.

The other things I hear complained about are poor quality rubber and electrical problems. The electrical system on the Stella is definitely more complex than an earlier P. The problems I had with mine seemed pretty typical of having passed through a couple owners.

I think the ongoing labor problems at LML had an unpredictable and negative effect on what could have been a great product. A complete crapshoot if you were buying one new and were expecting trouble free motoring. But a solid bet for a build your own bike project. Frame and engine case with good bones. Nothing wrong with that front fork and disc brake.
UTC

Molto Verboso
'07 GTS250, '07 LX150, '81 P200E, '78 P200E, '64 V90 and 3 Ciaos
Joined: UTC
Posts: 1171
Location: Tucson, AZ
 
Molto Verboso
'07 GTS250, '07 LX150, '81 P200E, '78 P200E, '64 V90 and 3 Ciaos
Joined: UTC
Posts: 1171
Location: Tucson, AZ
UTC quote
I thought 2005 was the last year they were offered prior to the strike. Quality was an abstract concept for that year.

As for cranks, I know of three crank failures on 2005 models and one 2008 model. I know the latter was due to autolube failure, because it sprung a leak below the air box.

The MO from there on out was to replace the crank and all the crankcase bearings with non-Indian stuff.
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4598
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4598
Location: London UK
UTC quote
A consideration for anyone reading this and wanting to change a stock crank on a scooter that already has a cylinder kit.
There is no situation where a 60mm crank will be slower than the stock crank. Apart from the additional cost of the crank, it's like free power.
@kowalski avatar
UTC

Addicted
2005 Stellalossi 177 Fe
Joined: UTC
Posts: 519
Location: MA
 
Addicted
@kowalski avatar
2005 Stellalossi 177 Fe
Joined: UTC
Posts: 519
Location: MA
UTC quote
It's actually fairly easy to track crank failures due to the known defect of pressing the cheeks too tight to the bearing because it happens in a pretty distinctive way. See photo above. Unless you ran your 2T dry, a bearing that looks like that means the manufacture was defective.

The reason this problem has been underestimated is that, when new, most Stellas were sold to dilettantes who didn't ride them hard and didn't ride them far. Again, Rob Hodge's data was from around 2010. At that time, there were still hundreds, if not thousands, of low mileage Stellas sitting mostly unused in people's garages (even today, the 700 mile Stella in DOD is not that unusual). The 2010 data tells us nothing about the failure rate as those scoots have accumulated mileage over the last 14 years.
OP
UTC

Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
 
Member
Stella
Joined: UTC
Posts: 39
Location: Detroit
UTC quote
I'm hearing all you....

Lots of good info.

I'm thinking that come January when the worlds frozen over my Stella will be getting a new crank

Not the thing I really want to do but sounds like the safe thing to do baised off all recomendations on this thread.

Don't want to sound like I was grasping at straws earlier but I've never delved that deep into wrenching on an engine, kinda nervous. But hey, probably get another 16 years of good riding out of it.
@orwell84 avatar
UTC

Ossessionato
Joined: UTC
Posts: 3199
Location: northern New York
 
Ossessionato
@orwell84 avatar
Joined: UTC
Posts: 3199
Location: northern New York
UTC quote
TheWizard wrote:
I'm hearing all you....

Lots of good info.

I'm thinking that come January when the worlds frozen over my Stella will be getting a new crank

Not the thing I really want to do but sounds like the safe thing to do baised off all recomendations on this thread.

Don't want to sound like I was grasping at straws earlier but I've never delved that deep into wrenching on an engine, kinda nervous. But hey, probably get another 16 years of good riding out of it.
Very reasonable idea to enjoy what you have for the season and save the kitted engine build for the 8 months of rustbelt winter to come. It's a learning curve and there are always parts to wait for no matter how well you plan. It's much less frustrating in the winter when you can take your time.
DoubleGood Design banner

Modern Vespa is the premier site for modern Vespa and Piaggio scooters. Vespa GTS300, GTS250, GTV, GT200, LX150, LXS, ET4, ET2, MP3, Fuoco, Elettrica and more.

Buy Me A Coffee
 

Shop on Amazon with Modern Vespa

Modern Vespa is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com


All Content Copyright 2005-2024 by Modern Vespa.
All Rights Reserved.


[ Time: 0.0180s ][ Queries: 4 (0.0051s) ][ live ][ 313 ][ ThingOne ]