Mon Jan 27, 2020 7:36 pm

Hooked
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Hooked
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Mon Jan 27, 2020 7:36 pm linkquote
Had this on a shelf, I was told it was a Hotrod Al Alpha kit. I have been weary to run it because of the spots in the bore this looke like the were knocked with a porting tool.
Would those knicks be problematic if they are smooth enough not to snag a ring?
Or would this just be a good model, start fresh on another cylinder?











Mon Jan 27, 2020 7:50 pm

Ossessionato
'20 300GTS Super Tec '09 250 GTSie '75 Rally 200 '79 P200 '09 Stella 221
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Ossessionato
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Mon Jan 27, 2020 7:50 pm linkquote
I ran one of those with a Vortex for one summer. Good running stockish motor.
Tue Jan 28, 2020 5:41 am

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Tue Jan 28, 2020 5:41 am linkquote
Personally I wouldn't be worried about the marks, could be casting flaws. If it were mine and everything else was in specification I would run it. My reasoning is there are larger port holes that the rings open into every time it moves in the cylinder. The marks also look like they are limited to where there are openings, so the ring isn't trying to seal the cylinder under pressure at that point. If the marks were in the combustion area where pressure is built up there would be a leak.

Last edited by Christopher_55934 on Tue Jan 28, 2020 2:50 pm; edited 1 time in total
Tue Jan 28, 2020 2:43 pm

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Tue Jan 28, 2020 2:43 pm linkquote
Came with a modified head too, I will have to check and see how everything lines up with the new 60mm stroke crank.
Tue Jan 28, 2020 5:25 pm

Ossessionato
'20 300GTS Super Tec '09 250 GTSie '75 Rally 200 '79 P200 '09 Stella 221
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Ossessionato
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Tue Jan 28, 2020 5:25 pm linkquote
Reach out to Al, I'm certain he would love to give you the low down with regards to building your motor. IF You have problems reaching him, PM me
Tue Jan 28, 2020 6:07 pm

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
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Veni, Vidi, Posti
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Tue Jan 28, 2020 6:07 pm linkquote
Is that just surface marks or is it pitted?
Tue Jan 28, 2020 7:34 pm

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Tue Jan 28, 2020 7:34 pm linkquote
It is pitted, looks like whatever was used for porting hit the cylinder wall accidentally. No sharp edges though, seems like a ring would glide right over. I was never sure if it would create some other sort of problem.
Tue Jan 28, 2020 9:38 pm

Jet Eye Master
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Jet Eye Master
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Tue Jan 28, 2020 9:38 pm linkquote
Lot of work been done in there. Ports look a bit wide for those stock rings. It will run but the rings might wear out quickly.

If you re-bore it to clean the marks, put in a thinner ring piston.

Have a measure of the ports from the top of the cylinder, see how much has been done.

Al's O tuned heads usually slip inside the cylinder to close the squish. These heads are quite a rare item these days.
Tue Jan 28, 2020 9:50 pm

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Tue Jan 28, 2020 9:50 pm linkquote
I also have one of his Alpha kits on my shelf, and it just has the standard shaped head as well. No recesses or O rings. I'll have to double check which piston currently i have for it. The original piston didn't last too long in the cylinder. I have a new replacement on the shelf ready to go, but i can't remember if it's a GS one or not.
Wed Jan 29, 2020 3:15 am

Veni, Vidi, Posti
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Veni, Vidi, Posti
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Wed Jan 29, 2020 3:15 am linkquote
Can you open up the GS piston to match the way he did the Piaggio piston? I've never seen one. I know with their 177 pistons the reinforcement is in different location to the originals.
Wed Jan 29, 2020 6:24 pm

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Wed Jan 29, 2020 6:24 pm linkquote
If I were to have the bored to clean things up, do these pistons have a good reputation? Thinner rings.
https://www.sip-scootershop.com/en/products/piston+grandsport+200+cc+_12090000
Wed Jan 29, 2020 7:52 pm

Jet Eye Master
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Wed Jan 29, 2020 7:52 pm linkquote
Yes a GS piston will work but a Malossi piston is the best choice
Thu Jan 30, 2020 2:31 pm

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Thu Jan 30, 2020 2:31 pm linkquote
Replacement malossi piston and rebore?
Thu Jan 30, 2020 5:46 pm

Veni, Vidi, Posti
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Thu Jan 30, 2020 5:46 pm linkquote
Which Malossi piston fits a stock-ish bore?
Thu Jan 30, 2020 6:49 pm

Jet Eye Master
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Thu Jan 30, 2020 6:49 pm linkquote
If re-boring the cylinder, re-sizing just costs a little more. Single ring MHR piston will make the most power. Transfers come in near flat but the huge boost port might need raising after the re-size. There is no future oversize for Malossi so this would be a one shot deal.
Thu Jan 30, 2020 11:04 pm

Veni, Vidi, Posti
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Thu Jan 30, 2020 11:04 pm linkquote
If you take a mm out of the bore, won't you be changing the shape of the transfers? The exhaust not so much because it goes off pretty much perpendicular to the bore. Also does it have an effect that the transfers are made shallower?
Fri Jan 31, 2020 8:44 pm

Jet Eye Master
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Fri Jan 31, 2020 8:44 pm linkquote
Is actually mm each side. Main transfers are near the same Because of the 1960's entry angle they move closer to a better position but the angle is still too strong. Generally the same only the boost lowers enough to worry about but the OPs barrel has had the big boost job and is probably way higher than stock anyway. The other benefit of using a Malossi piston is it will be 210cc after.
If anyone is ever re-boring any 200, tuned or not, any piston is way better than the original Meteor. They are just so bad in every way.
Fri Jan 31, 2020 9:36 pm

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Fri Jan 31, 2020 9:36 pm linkquote
Meteors are bad in every way^^^



Mon Feb 03, 2020 9:13 pm

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Mon Feb 03, 2020 9:13 pm linkquote
Decided to fit the malossi piston. On the stockncyinder or modified stock cylinder with a 60mm crank, running a 1.5mm spacer at the base lends itself to a higher revving setup while running the spacer on the head lends itself to a tourquier setup?
Mon Feb 03, 2020 10:25 pm

Ossessionato
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Mon Feb 03, 2020 10:25 pm linkquote
Declan wrote:
Decided to fit the malossi piston. On the stockncyinder or modified stock cylinder with a 60mm crank, running a 1.5mm spacer at the base lends itself to a higher revving setup while running the spacer on the head lends itself to a tourquier setup?
FYI you don't need a 1.5mm spacer. A stock cylinder with a longstroke crank brings the piston crown flush to the top of the cylinder. The cylinder was designed originally for a 60mm stroke but they ditched it in the process. On my ratty PX o-tune I used a 0.5mm packer at the head side to keep compression down and things cool...
Wed Feb 05, 2020 11:16 pm

Jet Eye Master
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Wed Feb 05, 2020 11:16 pm linkquote
Be sure to get the Vertex Malossi not the Asso. Both work but the Asso needs even more cutting. All three Windows will need some minor alignment.

If you measure the port heights it will determine if you need a packer at all, as Safis said it will run fine without one but if you measure the durations we can predict the outcome.
Thu Feb 06, 2020 2:44 am

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Thu Feb 06, 2020 2:44 am linkquote
oh someone danced with the miller
looks a bit oldschool
I would see some milling potentials


Honestly, the damages dont matter
This cyloinder is NOT defect

Roughen the running surface
Use new rings and there u go
It doesnt do any harm to the rings

BUT what i recommend, measure cyl timings.
Just opned ports, and everything ported
show little effect when the timings are still not optimized

small blowdown stays small blowdown and will limit the performance

Last edited by freakmoped on Thu Feb 06, 2020 3:03 am; edited 1 time in total
Thu Feb 06, 2020 2:52 am

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Thu Feb 06, 2020 2:52 am linkquote
SaFiS wrote:
Declan wrote:
Decided to fit the malossi piston. On the stockncyinder or modified stock cylinder with a 60mm crank, running a 1.5mm spacer at the base lends itself to a higher revving setup while running the spacer on the head lends itself to a tourquier setup?
FYI you don't need a 1.5mm spacer. A stock cylinder with a longstroke crank brings the piston crown flush to the top of the cylinder. The cylinder was designed originally for a 60mm stroke but they ditched it in the process. On my ratty PX o-tune I used a 0.5mm packer at the head side to keep compression down and things cool...
These infos do have potential
Lets start from the beginning


1) Longstroke needs a top head gasket NOT a bottom gasket
old wrong info to liftvthe cyl. Its about TIMINGSs
Just raising barrel lowers the blowdown, raises the exhaut oort timing which is both bad. It narrows the band and costs performance

HEAD GASKET it is.
for 210 & 177


2) sport 210 with longstroke does come over the top of the cyl
Its does not stay even with the top, only 57mm does

Here explained at a sport 210
https://www.youtube.com/watch?v=zTYO4E61wr8


As malossi squish is always too little
Sometimes only 0,5mm which is rubbish

Use a 2mm top spacer to get a healthy squish
Of course again pla center the head with the gasket

Asso or vertex piston (2016 on), both are fine
Older asso needs a bit more machining





Setup tip
2mm top gasket
65% ex port
Opened piston

Intake timings 190-200degree
Idel is 10degree oveleapping
BUT only if the rotary valve tolerance is 0,05mm
Otherwise blowback issues = defect rotary VALVE

Sipv2 tap
2,5mm mj bore
All mj corrected

And it will hit clearlly over 20hp at the wheel with just a box
polinibox is the best.

Last edited by freakmoped on Thu Feb 06, 2020 3:14 am; edited 5 times in total
Thu Feb 06, 2020 2:58 am

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Thu Feb 06, 2020 2:58 am linkquote
omg. forgot this super annoying link posting issue of this old forum software... all corrected!

to add some moved pics for more. Info

Malossi sport 210 timings
https://www.youtube.com/watch?v=c0KiflUmGgQ

Intake timings optimizing
https://www.youtube.com/watch?v=9zGBeT1YrD0

Ultimte timings guide
https://www.youtube.com/watch?v=MvGNkw1g6C8

Rotary valve tolerance explained
https://www.youtube.com/watch?v=gnWy7WKmfKs

Squish guide
https://www.youtube.com/watch?v=D9wG6vZrrkw

main jet bore
https://www.youtube.com/watch?v=K7TJXHEAfaA

new sip v3 fuel tap
https://www.youtube.com/watch?v=_fZMdXSu2CU

just pnp 210cc? then thats your guide
https://www.youtube.com/watch?v=t3CRLNi0kbE

Last edited by freakmoped on Thu Feb 06, 2020 3:19 am; edited 1 time in total
Thu Feb 06, 2020 3:02 am

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Thu Feb 06, 2020 3:02 am linkquote
Questions pls better over fb page
As i am rarely in formus and esp
Here

Drive safe!
Greetz
Sun Mar 01, 2020 2:33 pm

Hooked
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Sun Mar 01, 2020 2:33 pm linkquote
Sent the cylinder to Gickspeed to be bored for the Mallossi MHR piston. Looks great, defiently feel good about running this now.
The cylinder and head had previously been modified. Head fits into the cylinder and has an o-ring to seal.
Looks like it will need. 1-1.5mm base plate to completely open the exhaust port. Also need to order an oring.











Sun Mar 01, 2020 2:34 pm

Hooked
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Sun Mar 01, 2020 2:34 pm linkquote
The way the head and cylinder were modified makes the spacer in the head a difficult option.
Sun Mar 01, 2020 2:48 pm

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Sun Mar 01, 2020 2:48 pm linkquote
Without a spacer the piston will hit the head cranking over by hand, a custom spacer between the head and cylinder would help, but a spacer at the base will allow the piston to completely clear the exhaust port and keep the piston away from the head.





Sun Mar 01, 2020 3:44 pm

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Sun Mar 01, 2020 3:44 pm linkquote
Declan wrote:
Without a spacer the piston will hit the head cranking over by hand, a custom spacer between the head and cylinder would help, but a spacer at the base will allow the piston to completely clear the exhaust port and keep the piston away from the head.
Have you figured out what your timing numbers are and what they will be with a base spacer? If it were mine I would be contemplating a base spacer as long as timing numbers supported it. If you put a spacer on top, you won't get the benefit of the o-ring on the sealing surface for the head.
Sun Mar 01, 2020 3:59 pm

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Sun Mar 01, 2020 3:59 pm linkquote
Haven't measured timing numbers, but between the head , and eye balling things the base spacer looks like the most logical solution.
Sun Mar 01, 2020 5:21 pm

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Sun Mar 01, 2020 5:21 pm linkquote
Looks great mounted up to the cases. Looking forward to seeing it done and on the road. Glad i could help out with boring the cylinder for you.

JG
Sun Mar 01, 2020 7:28 pm

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Sun Mar 01, 2020 7:28 pm linkquote
Looking good so far. To get this to go you're going to have to measure the transfer ports. Deciding on the base packer thickness is everything.
Is that a 60mm crank?
Mon Mar 02, 2020 3:27 pm

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Mon Mar 02, 2020 3:27 pm linkquote
60mm crank
Mon Mar 02, 2020 7:17 pm

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Mon Mar 02, 2020 7:17 pm linkquote
Lot of work done on that cylinder. I imagine it is set to have the piston flush at the top.

If you measure the transfer port to the top. And exhaust port to the top. We can tell how it will go.
Tue Mar 03, 2020 2:57 am

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Tue Mar 03, 2020 2:57 am linkquote
Jack221 wrote:
Lot of work done on that cylinder. I imagine it is set to have the piston flush at the top.

If you measure the transfer port to the top. And exhaust port to the top. We can tell how it will go.
a bajillion moons ago Al and i were talking about this, and his whole idea behind the SS and the Alpha was that it was supposed to go on a stock crank so that it could be a bolt on. i'm guessing this is where the problem is stemming from.

granted, even with a stock motor it should be "blueprinted" and double checked for optimum performance, but it would be damn near close.

-g
Tue Mar 03, 2020 10:30 pm

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Tue Mar 03, 2020 10:30 pm linkquote
I will work on getting some measurements, worked on by brothers scoot tonight, slight frustrations stemming from what should have been an easy task.

I hadn't planned on running this cylinder when I opted for the new crank. In hindsight I could have avoided problems. I am hoping the base spacer will help, it appears that it will at the bottom of the stroke the piston is hanging over the exhaust port about the same distance it is protruding above the cylinder at the top of the stroke.

Worse case scenario I can run my stock cylinder, but I hope this will work out.
Sat Mar 07, 2020 12:02 pm

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Sat Mar 07, 2020 12:02 pm linkquote
Still waiting on the spacer. I pulled the cylinder an measured 35.31mm to the top of the exhaust port and 47.23 to the top of the transfer port. 60mm crank. Isn't there a way to convert that to degrees? Does that do any good not knowing the squish?
Sat Mar 07, 2020 12:42 pm

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Sat Mar 07, 2020 12:42 pm linkquote
Declan wrote:
Still waiting on the spacer. I pulled the cylinder an measured 35.31mm to the top of the exhaust port and 47.23 to the top of the transfer port. 60mm crank. Isn't there a way to convert that to degrees? Does that do any good not knowing the squish?
You need piston top to the top of cylinder also, do you have reed valves or a rotary intake? If you have a rotary intake you need more numbers I'm not familiar with.

http://ddog.at/stz/rechnen.php


If you use chrome web browser it will translate to English for you.



Another option I've seen but am unfamiliar with.

https://lambretta-images.com/tuningh/port-timing-calculators/
Sat Mar 07, 2020 7:44 pm

Jet Eye Master
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Sat Mar 07, 2020 7:44 pm linkquote
Declan wrote:
Still waiting on the spacer. I pulled the cylinder an measured 35.31mm to the top of the exhaust port and 47.23 to the top of the transfer port. 60mm crank. Isn't there a way to convert that to degrees? Does that do any good not knowing the squish?
Well done. This will do fine. The squish is not the most important. Number 1 on the list is the transfer duration. From your measurements with 60mm crank this is 124.5 degrees when the piston is exactly flush with the top of the cylinder. Exhaust is at 175.5 degrees, which will do.

Going to pull really strong. Will go great with stock gearing. Ignition timing will need to be reduced a few degrees to 21 and the carb is going to need a significant upjet.

Not sure what exhaust you have but no need for an expansion pipe. Going to be considerably better than stock.
Sat Mar 07, 2020 9:20 pm

Hooked
1984 PX200E, Vespa 100 Sport, Vespa GS160, and a 1957 VB1 project
Joined: 04 Apr 2015
Posts: 247
Location: St. Louis
 
Hooked
1984 PX200E, Vespa 100 Sport, Vespa GS160, and a 1957 VB1 project
Joined: 04 Apr 2015
Posts: 247
Location: St. Louis
Sat Mar 07, 2020 9:20 pm linkquote
Thanks, how did you calculate That? I have a pinasco 24.24er carb, and a sip 2.0 exhaust, elf gearing. Picked up the sip exhaust cheap, but still considering a bgm touring box.
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