Peugeot 50cc Kit. Give me advice.

My plans are as follows:

50cc malossi kit

ported stock cases

sito exhaust (not an expansion chamber, but performs much better then stock)

16mm intake with large doppler reed

16mm sha carb (possibly phva carb)

My intentions are to build a 50cc engine that performs better then stock (aiming for an easy to reach 45), but still gets decent gas mileage and is reliable.

The sito exhaust is being chosen for two reasons. I want it to look stock. It's going on my 104. also, When I ran a stock exhaust with a polini 70 kit, it was super torquey.

I already have a super fast, gas sucking 103. I don't need two.

I'm posting this thread because I was just lectured by bret hoffman on the phone about how this kit wont do shit unless I put a high revving variator and a giant expansion chamber on the bike. Now I have my doubts, but I generally don't follow bret's advice anyways. Any opinions? Elliot, I heard you saying something in the background.

Re: Peugeot 50cc Kit. Give me advice.

It might rev higher because of port timing. Lighter weights in stock variator. High compression for mpg and power. You will do 45 mph. There are low profile non articulating expansion pipes available

Re: Peugeot 50cc Kit. Give me advice.

You might have bit trouble getting it to perform super well, oh the hours I have been sitting and reading about expansion chambers. Might I add it's so easy to calculate ~ max power for particular pipe is if you have a degree wheel and measuring tape. No I don't think you need a better variator, just modify the stock one. If you want more torque and something that won't burn up the motor so quick remember a longer pipe is better then a shorter pipe. Also look at pipes that have smaller dwell(belly or midpoint on the pipe) and longer cones. RPM's will eventually kill your motor, it's just more wear and tear. My 2 cents.. oh and Eric I'm going to be doing the same project :-) sounds like you will beat me to it.. I was even thinking of using a phva carb.

-naz

Re: Peugeot 50cc Kit. Give me advice.

Also Steve just gave out some great advice....

Re: Peugeot 50cc Kit. Give me advice.

🇮🇹💦 Of the Loin /

the 50 kits for french bikes are SUPER in the high revs

my moby bidalot 50 is amazing.

you can get away with stock pipe, but you really need to lighten the variator no matter what.

although if you slapped a doppler or a g2 on it, youd never wanna go back to sito pipe

Re: Peugeot 50cc Kit. Give me advice.

I know that an expansion chamber will make the bike kill. I don't want this bike do do what my 103 does though. I want a pretty french bike that I can go 45 on and wax the paint all the time.

There is tons of good information in here, and I will be lightening the weights in my stock variator.

Thanks for the advice!

Re: Peugeot 50cc Kit. Give me advice.

You are going to be so disappointed in your $200 cylinder that goes no faster than stock. 50cc kits have amazing potential but need to have the other parts of the puzzle in place to function right. heavy variator and no expansion chamber means no power band almost ever, and very mediocre performance. You'd be better off getting a 70cc kit and putting stock stuff on it. At least that would have some pick up.

Re: Peugeot 50cc Kit. Give me advice.

Oh and if you order the malossi weight set for there variators like the variotop they work on the stock variator fine. Cheap and easy way to have adjustable variator. Oh and the reason alot of the 50 like to rev so high is because the have extremely long durations for there exhaust. Let's say you take 180 degree open exhaust port you measure your exhaust from the midpoint of the crown to the midpoint of the rear cone and you have something around 25.5" then your pipe will be reaching it's maximum hp output around 12,000 rpm. :-)

-naz

Re: Peugeot 50cc Kit. Give me advice.

oh and by midpoint of the crown I mean midpoint of the piston crown. The calculation is also just a approximation so it might be off by inch or so one way or the other.

Re: Peugeot 50cc Kit. Give me advice.

Maybe you could find a big rear sprocket. The mild port and compression job on my red bike does 43 mph. Maybe you should port a stock cyl. Someday I plan to build a Peugeot 70-80cc for high torque, slow engine speed with a 40 or 45 tooth on the back. Someday

Re: Peugeot 50cc Kit. Give me advice.

i want one of the 72 tooth anodized rear sprockets. . .

some day

Re: Peugeot 50cc Kit. Give me advice.

so your saying you want to convert to some sweet #219 action?

Re: Peugeot 50cc Kit. Give me advice.

Re: Peugeot 50cc Kit. Give me advice.

Keep it coming. Keep it coming!

Re: Peugeot 50cc Kit. Give me advice.

Keep it coming indeed! I don't know very much french, but I figured this may help.

1225214682_peug1.jpg

Re: Peugeot 50cc Kit. Give me advice.

So, what would a good stock Peugeot cylinder port map look like? The cylinder I have (marked F) has tiny square transfers, and a really narrow and small exhaust port.

So far I've bored out the stock intake, and made a reed plate that uses trimmed down QT50 reeds. It's what I had sitting around. Also going to use one of my generic "Wang Poo" 15mm Dellortos. I also have a mini bike pipe that has a nice looking profile that will probably work.

I'll show you once I find the camera.

1225215069_peug2.jpg

Re: Peugeot 50cc Kit. Give me advice.

🇮🇹💦 Of the Loin /

yay you posted a peugeot 102 porting guide haha.

get a tomos or polini reed plate. bolts right up. wayyyyy better.

i would go to town on that exhaust port, raise it like 2mm, and widen it by about 2mm (1 on either side) and see what that does. you can also advance the timing by a couple degrees.

and of course slap on a puch ignition coil to make it reliable.

Re: Peugeot 50cc Kit. Give me advice.

i swapped for the bosch coil + HT coil and I couldn't be more pleased

Re: Peugeot 50cc Kit. Give me advice.

Has anyone made wiki entry for this? Might be worth while, since it takes a somewhat un-reliable ignition and makes it very solid.

Re: Peugeot 50cc Kit. Give me advice.

🇮🇹💦 Of the Loin /

i think i tried but as much of an internet nerd as i am i dont know if i can figure out the wiki

Re: Peugeot 50cc Kit. Give me advice.

Yeah I was trying to see if Ian would do it.... I'm to lazy to figure out how to post it to the wiki.

Re: Peugeot 50cc Kit. Give me advice.

Wow, my powers of observation are ... not so good.

The second page does say something about the 103 - run a 15mm SHA Dellorto, 3 balls in the variator and use a 12 tooth sprocket? I think....

Cutting the piston sides open makes sense.

I don't know if I want to raise the exhaust port on mine- the side transfers are only 1mm ahead of the exhaust- don't want the exhaust to open before the transfers, right?

Re: Peugeot 50cc Kit. Give me advice.

🇮🇹💦 Of the Loin /

hmm its been days since i ported peugeot, i didnt realize they were that close. raise the exhaust as much as youc an tho without passing the transfers. and yeah cut the piston sides.

home made speed parts

I bored out a stock intake.

1225943359_intake_bored1.jpg

Re: home made speed parts

opened up the bottom too.

1225943442_intake_bored2.jpg

Re: home made speed parts

opened up the reed plate, and used reeds off a qt50 (they were there)

I have a strange feeling my cylinder bore is chromed, I still haven't cut it.

1225943665_reeds.jpg
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