OP
UTC

Hooked
Joined: UTC
Posts: 497
Location: FI PKS
 
Hooked
Joined: UTC
Posts: 497
Location: FI PKS
UTC quote
Any suggestions which cylinder head I should buy for stock engine? How much compression original crank shaft can take? Some high compression cylinder heads are available. Has anyone tried them?

This is what I have in mind at the moment: http://www.sip-scootershop.com/en/products/cylinder+head+mmw+px200+for_13013935
@scooterist avatar
UTC

Molto Verboso
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1558
Location: Tucson, AZ
 
Molto Verboso
@scooterist avatar
71' Sprint Veloce , 05' Vespa PX150, 1978 P200E
Joined: UTC
Posts: 1558
Location: Tucson, AZ
UTC quote
I would stick with the original piaggio one unless you plan on doing a cylinder kit and changing the compression ratio and all of that. The stock can be had very cheap(used)
UTC

nothing at all
Joined: UTC
Posts: 9656
Location: westla
 
nothing at all
Joined: UTC
Posts: 9656
Location: westla
UTC quote
The compression ratios available are way to high on that head. You'll just keep chasing down dragons with that.

You'll take away from the charm of the p200 class which is its bullet proof-ness and abilities to take a licken and keep on ticken.
OP
UTC

Hooked
Joined: UTC
Posts: 497
Location: FI PKS
 
Hooked
Joined: UTC
Posts: 497
Location: FI PKS
UTC quote
Is 10,5:1 a lot, or too much? Originally compression ratio is only 8,8:1 which is not much I think.
UTC

nothing at all
Joined: UTC
Posts: 9656
Location: westla
 
nothing at all
Joined: UTC
Posts: 9656
Location: westla
UTC quote
Partanen wrote:
Is 10,5:1 a lot, or too much? Originally compression ratio is only 8,8:1 which is not much I think.
Those heads go up to 12 to 1.

Im just sayin they are made for specific builds. You don't wanna just go slappin high compression heads on stock motors....but its your money so go ahead.
OP
UTC

Hooked
Joined: UTC
Posts: 497
Location: FI PKS
 
Hooked
Joined: UTC
Posts: 497
Location: FI PKS
UTC quote
The example I gave is made for stock engine, and claimed compression ratio is 10,5 to 1. It comes with O-ring which would be good.

Usually increasing compression ratio is one of the easiest way to improve performance. Why not with Vespa, if crankshaft can handle more pressure.
@aviator47 avatar
UTC

Moderator
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
 
Moderator
@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
UTC quote
Feel free to ignore jimmyb and scooterist. However,

I would consider contacting SIP and ask why they clearly state, "FOR RACE USE ONLY", in RED, for the head you linked. There might just be a reason for that warning.

Then, as jimmyb said:"but its your money so go ahead".
OP
UTC

Hooked
Joined: UTC
Posts: 497
Location: FI PKS
 
Hooked
Joined: UTC
Posts: 497
Location: FI PKS
UTC quote
Why that attitude? I was asking experiences about cylinder heads if someone has already tried. If not, I could try it anyway.

Also Malossi 210cc "sport 2013" is "For race use only". Just like many other tuning parts are. In many countries it's not allowed to tune engines for traffic use. Kind of liability clause.
@mr10 avatar
UTC

Hooked
150 GLx, Rally 200
Joined: UTC
Posts: 256
Location: Netherlands
 
Hooked
@mr10 avatar
150 GLx, Rally 200
Joined: UTC
Posts: 256
Location: Netherlands
UTC quote
Dunno if shipping costs from the Netherlands are doable, but I've got a few origal p200 heads for sale.
@ginch avatar
UTC

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8697
Location: Victoria, Australia
 
Veni, Vidi, Posti
@ginch avatar
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8697
Location: Victoria, Australia
UTC quote
Aviator47 wrote:
Feel free to ignore jimmyb and scooterist. However,

I would consider contacting SIP and ask why they clearly state, "FOR RACE USE ONLY", in RED, for the head you linked. There might just be a reason for that warning.

Then, as jimmyb said:"but its your money so go ahead".
I understand why you made the comment and agree in this case, however the reason they have the warnings is that they are not TUV-approved and therefore not road legal in Germany.
OP
UTC

Hooked
Joined: UTC
Posts: 497
Location: FI PKS
 
Hooked
Joined: UTC
Posts: 497
Location: FI PKS
UTC quote
mr10 wrote:
Dunno if shipping costs from the Netherlands are doable, but I've got a few origal p200 heads for sale.
Thanks. I'll keep that in mind. But I'm looking for high compression head actually. I'm not sure if it's the right term but that's how it translates from my language.
@aviator47 avatar
UTC

Moderator
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
 
Moderator
@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
UTC quote
Ginch wrote:
Aviator47 wrote:
Feel free to ignore jimmyb and scooterist. However,

I would consider contacting SIP and ask why they clearly state, "FOR RACE USE ONLY", in RED, for the head you linked. There might just be a reason for that warning.

Then, as jimmyb said:"but its your money so go ahead".
I understand why you made the comment and agree in this case, however the reason they have the warnings is that they are not TUV-approved and therefore not road legal in Germany.
Hadn't thought of that. Thanks. No such limitations here. I learn something very day.
UTC

nothing at all
Joined: UTC
Posts: 9656
Location: westla
 
nothing at all
Joined: UTC
Posts: 9656
Location: westla
UTC quote
I thought it was more a item "disclaimer" so if you screw something up with their head its your fault.
@aviator47 avatar
UTC

Moderator
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
 
Moderator
@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
UTC quote
jimmyb865 wrote:
I thought it was more a item "disclaimer" so if you screw something up with their head its your fault.
jimmy-

Just for chuckles, I looked at the listing for the SIP Road exhaust, and it has the same disclaimer. I would guess that such parts are not certified for EU (or German) environmental standards. I know that Mrs Av's old LeoVince had a certification label.
@scooterraton avatar
UTC

Ossessionato
2 - Many
Joined: UTC
Posts: 3165
Location: Boca Raton, Florida
 
Ossessionato
@scooterraton avatar
2 - Many
Joined: UTC
Posts: 3165
Location: Boca Raton, Florida
UTC quote
Aviator47 wrote:
Ginch wrote:
Aviator47 wrote:
Feel free to ignore jimmyb and scooterist. However,

I would consider contacting SIP and ask why they clearly state, "FOR RACE USE ONLY", in RED, for the head you linked. There might just be a reason for that warning.

Then, as jimmyb said:"but its your money so go ahead".
I understand why you made the comment and agree in this case, however the reason they have the warnings is that they are not TUV-approved and therefore not road legal in Germany.
Hadn't thought of that. Thanks. No such limitations here. I learn something very day.
Yeah I worked with a guy from Germany. As he explained parts on vehicles must be replaced with OEM down to the tires. Pretty much any aftermarket part is labeled for race or off road use so it can be sold.
@aviator47 avatar
UTC

Moderator
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
 
Moderator
@aviator47 avatar
2006 PX 150 & Malossi Kitted Malaguti Yesterday (Wife's)
Joined: UTC
Posts: 12955
Location: Paros Island, Greece
UTC quote
Before anyone can really answer your questions, we would need to know exactly what "performance improvement" are you seeking? Top speed? Low end or mid-range torque? Have you ridden the scooter enough to determine the performance deficiencies you are concerned with?

Any "performance parts" can be installed on any engine, but as jimmyb and scooterist are suggesting, simply installing a "performance head" is really a partial job.

As to the crankshaft handling the increased compression, the forces of the compression stroke are minor compared to the forces of the power (combustion) stroke. Or are you asking about the power stroke and not sure how to express that?

I am guessing you want to take advantage of the Winter to do everything possible to avoid loss of riding time come warmer weather, and I sympathize with that. However, I would strongly suggest you determine what "performance improvements" you want in terms of performance parameters (speed, torque, power band), and then determine the parts necessary to achieve those parameters. For example, I found my PX150 a bit short of torque on our mountain roads. My local Vespa technician recommended I try the SIP-Road exhaust for that specific need, and that solved it. And since the stock exhaust needed replacement anyway, for just a few extra Euro. Also got a bit of top speed improvement, but can rarely use that safely on the roads here. Not much in the way of straight runs.

So, might I suggest you restate your question in terms of desired improvement in speed, torque, etc, and then let folks with serious "performance improvement" experience suggest solutions.
UTC

Molto Verboso
px200
Joined: UTC
Posts: 1269
Location: london
 
Molto Verboso
px200
Joined: UTC
Posts: 1269
Location: london
UTC quote
Hello


The TUV and vehicle certification can make changes difficult, if you follow the rules as a religion, you cannot change anything that was not present at the the time of certification.

So you cannot change the vehicle colour or the type of oil it is supplied with, nor can you add anything like racks etc, however it is not policed except for the exhaust if that is marked not for road use it is an MOT fail, if it is not marked it is down to the discretion of the tester (and the copper that stops you for excessive noise) europe has given us so much over the years.


It is enough to make you


Grumpy
OP
UTC

Hooked
Joined: UTC
Posts: 497
Location: FI PKS
 
Hooked
Joined: UTC
Posts: 497
Location: FI PKS
UTC quote
Fiddling things is my hobby at this moment. I have Gts which I Ride, this PX is for fiddling.

Malossi cylinder kit gives 2hp more without porting, I've been told. I don't want to do any portings for this original engine. So why not to try high compression cylinder head for 100EUR instead of buying 400EUR cylinder kit. As times goes by I could buy another engine which I could tune more. Do some porting to match with Malossi cylinder kit.

Increasing compression ratio should give more power, but not disturb nature of the engine. So it should give more performance and engine's nature remains the same. Basic rules, isn't it?
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: 0.0154s ][ Queries: 3 (0.0043s) ][ live ][ 313 ][ ThingOne ]