Tue Jun 08, 2021 8:06 pm

Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
 
Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
Tue Jun 08, 2021 8:06 pm linkquote
I scored a 2005 PX150 last year with only 300 miles on it and have since put on about 1000 more. I've put on a Polini box exhaust, the bigger SI 24 filter and rejetted. This gave a nice boost, but of course I'm looking at the next level. It's 2021 and there are dozens of cylinder kits available, especially if ordering from Europe.

Here are my criteria:
1. Aluminum cylinder & head
2. Keep offset plug
3. Broad torque range rather than high peak, though I would like to increase top rpm
4. Would much prefer to keep electric start and ring gear
5. Keep stock crank

What kit would you reccomend and why?

I'm also considering just porting & setting squish on my stock set, nothing to lose there.
Wed Jun 09, 2021 6:09 am

Hooked
1958 Allstate Super Cruisaire 2005 70cc Yamaha Vino
Joined: 23 Aug 2020
Posts: 364
Location: Philadelphia
 
Hooked
1958 Allstate Super Cruisaire 2005 70cc Yamaha Vino
Joined: 23 Aug 2020
Posts: 364
Location: Philadelphia
Wed Jun 09, 2021 6:09 am linkquote
VMC 177 Stelvio

Although that doesn't check off the keeping of the offset plug.
I just drilled a new hole in there then got some rubber plugs off amazon and epoxied the offset hole shut. Was very easy.

Jon Gick built it for me. He'll sing the praises of the cylinder to you.
Wed Jun 09, 2021 9:29 am

Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
 
Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
Wed Jun 09, 2021 9:29 am linkquote
Hmm that looks interesting, I havenít read much about VMC. How good is plug access for maintenance with it centered?
Wed Jun 09, 2021 11:39 am

Ossessionato
Joined: 26 Oct 2015
Posts: 2989

 
Ossessionato
Joined: 26 Oct 2015
Posts: 2989

Wed Jun 09, 2021 11:39 am linkquote
rhauff wrote:
I scored a 2005 PX150 last year with only 300 miles on it and have since put on about 1000 more. I've put on a Polini box exhaust, the bigger SI 24 filter and rejetted. This gave a nice boost, but of course I'm looking at the next level. It's 2021 and there are dozens of cylinder kits available, especially if ordering from Europe.

Here are my criteria:
1. Aluminum cylinder & head
2. Keep offset plug
3. Broad torque range rather than high peak, though I would like to increase top rpm
4. Would much prefer to keep electric start and ring gear
5. Keep stock crank

What kit would you reccomend and why?

I'm also considering just porting & setting squish on my stock set, nothing to lose there.
Since you are also considering dialing in your stock setup, i can tell you what i did on one of my 05 PX150's...

The stock PX150 cylinder ports are horribly matched to the PX case. I matched and flowed them. I also matched and flowed the stock 20/20 carb, airbox, and inlet. I then installed a Sito+, and drilled the "heart" in the airfilter. That brought the top speed of the scooter from a GPS'd 47mph top speed to a 60mph top speed. It also gave the scooter a boost of torque as well. I didn't play with any porting or squish, i just flowed everything. It was well worth the effort for me. It was all simple stuff that didn't cost much money.
Wed Jun 09, 2021 12:39 pm

Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2511

 
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2511

Wed Jun 09, 2021 12:39 pm linkquote
whodatschrome wrote:
Since you are also considering dialing in your stock setup, i can tell you what i did on one of my 05 PX150's...

The stock PX150 cylinder ports are horribly matched to the PX case. I matched and flowed them. I also matched and flowed the stock 20/20 carb, airbox, and inlet. I then installed a Sito+, and drilled the "heart" in the airfilter. That brought the top speed of the scooter from a GPS'd 47mph top speed to a 60mph top speed. It also gave the scooter a boost of torque as well. I didn't play with any porting or squish, i just flowed everything. It was well worth the effort for me. It was all simple stuff that didn't cost much money.
Good first hand information.
Thu Jun 10, 2021 7:14 am

Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
 
Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
Thu Jun 10, 2021 7:14 am linkquote
Whodatschrome, that is great information. That is a pretty significant boost using the stock parts. Did you pull the crank out for the inlet or transfer port matching? Any photos?
Thu Jun 10, 2021 9:02 am

Ossessionato
Joined: 26 Oct 2015
Posts: 2989

 
Ossessionato
Joined: 26 Oct 2015
Posts: 2989

Thu Jun 10, 2021 9:02 am linkquote
rhauff wrote:
Whodatschrome, that is great information. That is a pretty significant boost using the stock parts. Did you pull the crank out for the inlet or transfer port matching? Any photos?
It was quite a few years ago that i did that...maybe back in 2008, so i have no pics. I stripped down the cases competely to do all the work (including removing the crank). It doesn't take that long to strip down the cases, plus it's a great excuse to replace the shift cross, seals, and crank bearings (especially the fly side crank bearing). The flip side to all of this, is that it doesn't take anymore or less time to simply install an aftermarket cylinder kit. You'll get more HP and torque with a cylinder kit. But that wasn't my focus at the time. I just wanted to see what sort of gains i would get from matching and flowing all the stock parts. If you do go with a cylinder kit, i would invest into getting your cases welded up so that you can maximize the cylinder flow. Talk to J Gick (Gickspeed) about that.

Last edited by whodatschrome on Thu Jun 10, 2021 9:18 pm; edited 1 time in total
Thu Jun 10, 2021 9:10 pm

Molto Verboso
Joined: 03 Nov 2011
Posts: 1251
Location: Racing Capital of the World
 
Molto Verboso
Joined: 03 Nov 2011
Posts: 1251
Location: Racing Capital of the World
Thu Jun 10, 2021 9:10 pm linkquote
whodatschrome wrote:
It was quite a few years ago that i did that...maybe back in 2008, so i have no pics. I stripped down the cases competely to do all the work (including removing the crank). It doesn't take that long to strip down the cases, plus it's a great excuse to replace the shift cross, seals, and crank bearings (especially the fly side crank bearing). The flip side to all of this, is that it doesn't take anymore or less time to simply install an aftermarket cylinder kit. You'll get more HP and torque with a cylinder kit. But that wasn't my focus at the time. I just wanted to see what sort of gains i would get from matching and flowing all the stock parts. If you do go with a cylinder kit, i would invest into getting your cases welded up so that you can maximize the cylinder flow. Talk to J Glick (Glickspeed) about that.
No "L."















Thu Jun 10, 2021 9:25 pm

Ossessionato
Joined: 26 Oct 2015
Posts: 2989

 
Ossessionato
Joined: 26 Oct 2015
Posts: 2989

Thu Jun 10, 2021 9:25 pm linkquote
GickSpeed wrote:
No "L."
Glood glracious, my apologlies Jonathan! I feel like a iglnoramus now. I edited my posting above to the correct spellingl.
Thu Jun 10, 2021 11:00 pm

Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1698
Location: UK (South East)
 
Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1698
Location: UK (South East)
Thu Jun 10, 2021 11:00 pm linkquote
When people are looking for significantly more power and more extensive tuning work, I would never suggest a DR177, but your requirements would be met almost perfectly with the DR. The benefits of aluminum are negligible in your case, and an iron cylinder will give an upgrade path should it ever seize and destroy a piston.

Yes, some will say the DR is old technology, although I don't think the word technology belongs in this context, and if it ticks most/all of your boxes, who cares? It would certainly need careful preparation before installation, as they have a fairly rough finish. I used one on a PX150 with a better head (VMC CNC) that I had on my shelf. I decided against the VMC cylinder because it calls for a long stroke crank, but I'll use that for something else. The beauty of the VMC head on a DR is that it allows you to raise the cylinder and ports by 1.0-1.5mm without any machining. The raised port durations were important for my power objective, and they suit the other components like the SI 24 carb and in my case a BGM Touring exhaust. You can use the stock DR head, but you'd want to improve it.

I did use a mildly sporty crank, but it's still 57mm stroke. You also do not need to do any case welding and porting as the DR keeps the stock port shape and size. I did port mine, but only because I couldn't resist.

I always use the elestart on this particular scooter, and only had to file a tiny amount off the cylinder to accommodate the starter ring. I think the 1.5mm base packer helped with the clearance.
Fri Jun 11, 2021 8:05 am

Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2511

 
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2511

Fri Jun 11, 2021 8:05 am linkquote
swa45 wrote:
When people are looking for significantly more power and more extensive tuning work, I would never suggest a DR177, but your requirements would be met almost perfectly with the DR. The benefits of aluminum are negligible in your case, and an iron cylinder will give an upgrade path should it ever seize and destroy a piston.

Yes, some will say the DR is old technology, although I don't think the word technology belongs in this context, and if it ticks most/all of your boxes, who cares? It would certainly need careful preparation before installation, as they have a fairly rough finish. I used one on a PX150 with a better head (VMC CNC) that I had on my shelf. I decided against the VMC cylinder because it calls for a long stroke crank, but I'll use that for something else. The beauty of the VMC head on a DR is that it allows you to raise the cylinder and ports by 1.0-1.5mm without any machining. The raised port durations were important for my power objective, and they suit the other components like the SI 24 carb and in my case a BGM Touring exhaust. You can use the stock DR head, but you'd want to improve it.

I did use a mildly sporty crank, but it's still 57mm stroke. You also do not need to do any case welding and porting as the DR keeps the stock port shape and size. I did port mine, but only because I couldn't resist.

I always use the elestart on this particular scooter, and only had to file a tiny amount off the cylinder to accommodate the starter ring. I think the 1.5mm base packer helped with the clearance.
Where did you find the VMC head, I only found one site and its not in English. Iím interested in trying one on my DR180 cylinder to lower the clearance.
Fri Jun 11, 2021 12:40 pm

Ossessionato
73 & 74 Rally, 76 ET3, 80 P200, 06 PX150, 61 Ser 2, 65 Silver Special, 86 & 96 Elite 80s, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3995
Location: Oceanside, CA
 
Ossessionato
73 & 74 Rally, 76 ET3, 80 P200, 06 PX150, 61 Ser 2, 65 Silver Special, 86 & 96 Elite 80s, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3995
Location: Oceanside, CA
Fri Jun 11, 2021 12:40 pm linkquote
rhauff wrote:
Here are my criteria:
1. Aluminum cylinder & head
2. Keep offset plug
3. Broad torque range rather than high peak, though I would like to increase top rpm
4. Would much prefer to keep electric start and ring gear
5. Keep stock crank
So Iíll be the voice of keeping it simple! I poked around didnt see the aluminum Polini 177 on SIPís website but the cast iron version has made a few folks around me really happy. Ive installed them on two peoples scoots (one ported, one just bolt on) and they both blow away my old Malossi 166 (166, bolt on, 24/24, Polini box, 22 tooth clutch cog). Kit comes with the offset plug and there was minimal shaving on the cylinder wall for the E-start ring to clear the cylinder. Works fine with the stock crank however I would recommend you change your clutch tooth cog up 2 more. The stock gearing limits your top speed but with the 22 tooth in my Malossi, I top out at 64 mph. If youíre going to want higher speeds, Iíd look into an overdrive kit regardless of what kit you buy.

[quote=ďrhauffĒ]
I'm also considering just porting & setting squish on my stock set, nothing to lose there.
[/quote]

I actually had Hot Rod Al do that to my stock cylinder for giggles. It was better than stock, but not very close to the torque and power that an aftermarket cylinder provides. Acceleration was marginally better and topped out at 62 mph with the 22 tooth cog and 24/24 installed.
Fri Jun 11, 2021 11:03 pm

Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1698
Location: UK (South East)
 
Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1698
Location: UK (South East)
Fri Jun 11, 2021 11:03 pm linkquote
Lynnb wrote:
Where did you find the VMC head, I only found one site and its not in English. Iím interested in trying one on my DR180 cylinder to lower the clearance.
It came with a SuperG kit at a great intro price when they first hit the market. The SuperG is the iron version of the Stelvio but has the same CNC head. I did not use the cylinder and piston due to poor port timings with 57mm stroke.

https://www.10pollici.com/en/homepage/classic-vespa/engine/cylinders/largeframe/head-for-cylinderkit-vmc-177cc-stelvio-and-superg-machined-aluminum-vespa-125-px-ts-sprint-v-.2.1.26.gp.8695.uw
Wed Jun 16, 2021 1:48 pm

Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
 
Member
PX150, LX150
Joined: 05 Sep 2020
Posts: 6
Location: Minnesota - USA
Wed Jun 16, 2021 1:48 pm linkquote
Well that's 2 solid reports of getting 60-62 mph with the stock cylinder. Thanks whodatschrome and MJRally! I think I'll go that route for now as I'll learn a few things and probably have enough speed to drive my local 55 mph highways.

The VMS cylinder does indeed look like a very nice option, as long as plug access for service is still acceptable. I'll look into that down the road.
  DoubleGood Vespa T-Shirts  

All Content Copyright 2005-2021 by Modern Vespa. All Rights Reserved.

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.

Shop on Amazon Smile with Modern Vespa
[ Time: 0.0348s ][ Queries: 24 (0.0132s) ][ Debug on ][ 156 ][ Thing Two ]