Piaggio Zip 4T cylinder upgrade advice

Hello,
After long freezing winter (all January was with negative temperatures) I manage to begin with some activity on my Piaggio. I wasn't sure of my ability to complete the job and decide to check some local so called "scooter services". Believe me you never seen such an alcoholics in one place. I collect needed tools and decide to begin the work. I read and watch so many books and vids that make me feel more and more confident.
First step was engine removal (this thing was the scariest for me). There is no step-by-step or how-to tutorials for that operation for Piaggio Zip 4T. This is the sequence of my work for engine removal:
1. Remove battery;
2. Remove exhaust;
3. Remove some electrical connection on the right side (just forgot how it was in English);
4. Remove rear brake cable;
5. Unbolt air filter box;
6. Unbolt the carb from cylinder head;
7. Unscrew the starter motor cables - this was unpleasant surprise for me because no one ever speak about this;
8. Unscrew the bottom of rear shock;
9. Remove the big long bolt who is connecting the engine to the frame - here I have another shitty surprise - there was something round and plastic that was on the way of the long bolt. I have to lift up very high the scooter in order to remove the bolt.
After that the work was like a song. I know what and how to do everything. Here are some pics


Everything goes perfect till the moment of using torque wrench. I borrowed one from a friend. It was cheap and shitty wrench and unprecise setting leads to this

I manage to cut one of the studs. I'm lucky that I cut it on the top side and was able to remove it. So now I am waiting for four brand new studs and will continue my job. So never use some shitty crapy lidl/kaufland/billa tools.
Now I want to clear how to rejet my carb and any advice will be helpful.

 

OK, friends ... I receive my 4 genuine studs and one hose which was cut


and was able to finish the work. Replacing the studs was easy. Also set valve clearance to 0.10 intake and 0.15 exhaust and rebuild the engine



Next step was to rejet carburetor from 75 to 80. Just in case I bought Naraku set of jets from 80 to 90 but as I saw in some videos recommended jet is 80.

So today I assemble the scooter and after 15-20 kicks the old Piaggio starts with virile voice.
First impression after around 10 km (6.2137119224 miles) was impressionable feel of engine power and may be increase the top speed. I said may be because I have to ride with no more then 40 km/h (24.855046528 mi/h) first 500 km (310.68559612 miles).

 

Do you know what is this?

 

Looking at the dial, and the Nm scale (newton meters), I'd say it was an old torque wrench gauge.
Try clamping it in a vice, put a wrench in the square hole and turn it, see if the dial moves

 

Yes, this is shitty soviet torque wrench. It was made in 1990!!!

 

Please need another advice about choosing exhaust. Again the cheapest is winner. I found these 3 are compatible for my Piaggio Zip:
1. Tecnigas GP4

2. Tecnigas Next - R

3. Turbo Kit - this one is a little bit expensive for me

So, after almost 200 km I noticed that the scooter has more power according previous engine. It feels very good on uphill. I didn't reach top speed yet but what I feel it will be not much more (then 50-60 km/h). In other way acceleration is mad. I guess that I have to work out with roller weights to reach best performance.

 

They are all decent exhausts, BUT, do not buy one that has chrome.
You will obviously have to play with the carb jets and rollers to get the best of the exhuast performance.
It all depends on your personal budget and how you want the bike to look.

 

The technigas Nex R is a two stroke exhaust it wont work well with your fourstroke engine as you do not need the back pressure it produces.

its a choice between pipe number 1 the technigas GP4 or the turbo kit. most fourstroke exhaust come with a baffle insert usually a small screw holds them inplace, depending on the law and police you maybe able to remove them so you get that sweet Brap brap sound these exhausts produce , the baffle inserts are there to cut down on noise .

 

Thank you for the replies. According the site of tecnigas Next-R is for PIaggio Zip 4T
http://www.tecnigas.com/o/model.php?codi=17&cat=2&idioma=en
Here is one video shoot by hand

 

To be safe i would contact the shop before you by a Next R and make sure its for a fourstroke......

that pipe is an expansion pipe it creates an acoustic wave form that travels up and down the exhaust , its designed for twostokes .

notice it is very different to the other two pipes they just have an end can they dont have a expansion chamber because they are fourstoke and have valves that close off the exhaust port fully when the intake port valve opens hence you do not loose some of the fual/air charge thats forced into the cylinder . thats the reason a twostroke has a different pipe like the next r .

i would make my choice between the technigas gp4 or the turbo kit because these are for fourstoke motors. the technigas next r is only for twostrokes, its the same as the technigas trek and the leo vince tt both of those are also expansion pipes to . ( trust me on this i run twostroke and that next r is a twostroke pipe buddy )

 

Sorry but Nikitzo is right on the exhaust, it doesn't look exactly like the picture but very close and it is made for the 50 4 stroke 2 valve engine.
I had a scoot shop send me one and it didn't fit the 4 valve because of different size exhaust port. Been working on the 4 valve a lot and maybe start a new thread because there is way to much misinformation in this single thread alone. also like to find someone with knowledge on the final drive gears specifically on the newer 4 stroke 4 valve 50 typhoon

 

Hello, just pass 500 km after kit. I have to retighten engine head and check valve clearence. After that I will change the oil

 

Buy a piaggio lump with cdi .. 125 180 200 250.. all carb lumps

 

In your earlier statement about babying the engine not going over 40 km/h is the wrong approach, for piston rings to seal up they need a workout especially with hard alloy plated cylinders.

 

Hi, english is not my native language so please be patient with me.
Petey - I guess that you mean to buy Piaggio CDI for 125, 180, 200 or 250 cc engines? I can't figure it out how this will improve my engine? Can somebody explain me? As I know cdi's task is to provide right current in right moment to the spark plug. I guess that custom cdi's have abillity to adjust ignition timing. Do cdi's are connected with rev limitations?
yahmon - what is the correct approach according you? I'm following manual which came with my cylinder kit (bottom of page 15)
http://www.motorparts.it/documenti/pdf_libretti/ISTRUZIONI_9925150.pdf

 

i can't speak for every vehicle but for the typhoon 4 valve 4 stroke 50cc i bought malossi cdi, it did increases rev limit and supposedly has better performance timing. the cdi unit hides up front behind the key and also reads temp and controls choke and fuel temp

 

Just arrived

 

let me know what you think, got mine today also. That plug in the back only has 8mm hole, the inner perforated pipe is 14mm. I took plug out for now thinking it simply to small for 80 cc engine

 

first installed malossi variator today, was not impressed with the fit of the splines on the crank, seems rather lose compared to the stock that fits nice and snug. Used the 6.1 gram rollers that were supplied and malossi blue rear spring giving it nice revs shifting all the way to about 70 km/h and topping out at 85km/hr at the rev limit. After that changed the pipe it seems like it gained a bit of torque taking of better and pushing faster in a head wind.

 

yahmon - can you please describe the changes you made to your scooter?
Because when I installed malossi multivar (mine was supplied with white spring) on my stock engine it was very very slow.
According Tecnigas the first impression was only the weight reduce according stock exhaust.
Tomorrow I will re tighten cylinder head, check valve clearance, change engine oil and mount new exhaust.
Another thing I was thinking about is overheating of the engine. Till now I was riding like this:

I will refit this shell tomorrow but I'm afraid of overheating. Daily temperatures during the summer here are over 30 degrees Celsius. What do you thing is it good idea to cut several slots with dremel tool to this part? Something like this: