P200e not running right

[cayote]

Hello I need advice on my p200e 1983 y reg .I’ve just purchased.the man I purchased it of said he didn’t no what it had been done on it so on inspection it’s got a mallossi mhr kit on it and a dellorto phbh 30 bd carb on it .the problem is it starts up first kick and ticks over the first couple of reves sound crisp then it sounds like it chocking up .when I try to ride it it revs abit then chokes up abit like fuel starvation.I’ve put new stator plate on/ fast flow tap/new cdi/plug/cleaned carb and jets out twice but still doing the same thing .any help would be appreciated

[Jock]

Check your gear box oil , might be a drive side seal gone , hopefully not -

[cayote]

Ok will do

[gpowell]

Was it running okay when you purchased or is the a "new" issue.

[cayote]

Just checked needed a bit in but not empty.what is the seal you mentioned and is there any other symptoms with this seal gone

[cayote]

No it was running the same as it is now I just started it there sounded ok so i bought it. He had about 50 bikes of all sorts .

[cayote]

Is there a way to check if the seal is leaked without taking the engine out or splitting it

[Jock]

Drain the gear box oil - petrol in there , seal has gone -if lots of white smoke ,seal has gone ( drive side seal ie clutch seal ) it could be a hairline crack in casing - im guessing at the problem , could be something like a gasket missing on carb, carb rubber might be split or not tightened correctly - i do hope it is a simple / easy fix

[Jock]

Check it without the petrol cap on - if ok - then the cap has dirt in the tiny centre hole blocked

[cayote]

Update on the p200 .I had it worked on by a scooter specialist he replaced all crank bearings and seeks new flywheel all jetted up correctly and still doing the same he said he’s done all he can and he thinks that the carb is leaning back to much and it’s not getting enough fuel .but I Carnt seem to find a inlet with more ov a curve to make the carb more level . Or is there a carb I can fit back on instead any help appreciated thanks

[adrian]

Delorto carbs will work perfectly well at an angle , mine is angled up and to the side with no issues. Might be a silly question, but is the fuel pipe kinked or maybe to long 🤔 basic stuff that you have probably checked, where abouts are you based ? Might be someone on the forum who could cast a second pair of eyes over it

[cayote]

yes ive replaced the fuel pipe and put a fast fuel tap on. its getting me down now if a scooter mechanic carnt sort it but he is going on holiday tomorrow so said he didnt have anymore time .i was oing to buy a 26 26 carb with 135 main jet .  .im in chesterfield 

[gpowell]

I have seen PHBH carbs very badly set up.

What jets are in it?

Does it rev clean on the stand?

[cayote]

I’m not sure what jets are in it the scooter bloke put other ones in and it run even worse . So I’ve bought a new 26/26 carb and box exc and put it on yesterday and it runs and sounds really good so it was the dellorto after all £500 later. Thanks for everyone’s help and advice

[gpowell]

Which 26 is it.

The straight spaco based on the 24 or a BGM, Pinasco with opened up fuel ways.

With a mallossi kit you should increase the pilot and main jet.

Start with a 135 and see what happens, come down.

Put a 52/140 pilot

Get a pack of main jets from KMT down to 128.

Air screw at 2 and a quarter out to start.

You may want to consider the air filter mod as well

I rate the si carb for mild tuning, have use a 26 for a long time.

[cayote]

It’s a spaco I’ve just put it on as standard to see if it was the carb and run it s few miles . And then going to do the 2.5 mil drill to the jet and a bigger jet . What is the air filter mod ?

[gpowell]

There are a few little mods to do but beware drilling the main jet passage in the float bowl.
I open up the banjo and the in the inlet in the float chamber.
The air filter mod. vespalabs.internetscooter.com/wiki/vespa-tuning/carburetors-carburetion/air-filters/air-filter-hole

[cayote]

You say beware is this because it will take too much fuel ?also how do you older the banjo

[gpowell]

It not about using more fuel, it about not doing it correct and ruining the carb.

Have a read of this

vespa.proboards.com/thread/4947/si-carb-modifications-considerations-celebrations

[cayote]

Thanks for that really good info