P200 Swapping 20/20 for 24/24
Post Reply    Forum -> Not-So-Modern
Author Message
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Mon Mar 22, 2010 8:32 am quote
I've searched and searched and still have some questions on this upgrade.

First off a littlet history. I put a 226 pipe on and we tried a Spaco 24/24. It was running rich and needed to run pretty small main jet to get it rideable. Although it was rideable it wasn't nearly as smooth as the stock 20/20 with stock pipe.

After a day of riding I put the 20/20 back on and up jetted the main from 98 to 105 (I'm at 4500 ASL in Reno). It's running pretty smooth now maybe a touch rich, but after it's warm it goes good and smooth.

Now my questions:

1) I didn't do anything to the airbox when putting the Spaco on. Just bolted it up. I read that you need to remove something or cut something below the airbox but never found any pics or details. I can see that the hole in the airbox (or some aluminum piece below it) with the carb off is oval, and the 24/24 is round which is what i think may have been causing the issues and the need to run such a small jet with the 24/24. (Lack of air). Anyone have pics of more details on how i should go about properly modifying my stock 20/20 equipped p200 to take a 24/24?

2) Which 24/24 should i try to get ahold of 24/24E or G. I want to keep the oil injection intact. (anyone have one for sale)

The bike runs good now with the 20/20 and 226 but from what i've read the 24/24 is the ticket for a P200 especially with the pipe.

Thanks
Member
2013 Piaggio Fly 150
Joined: 07 Aug 2009
Posts: 36
Location: Redmond, Washington
Mon Mar 22, 2010 10:07 am quote
Re: P200 Swapping 20/20 for 24/24
hurleyskis wrote:
I've searched and searched and still have some questions on this upgrade.

I read that you need to remove something or cut something below the airbox but never found any pics or details.
Thanks
Here is a link to the P-Series Air Box Mod. I am told it works quite well.
http://www.vespalabs.org/Vespa_Tuning/Air_Filter_Hole
Moderator
VNB VSC VBC VSX
Joined: 28 May 2008
Posts: 4844
Location: Hustletown, TX
Mon Mar 22, 2010 10:27 am quote
link above is for an airfilter mod... ? (I am assuming you are using the correct airfilter?)

Anyway, I think the OP needs to mod the airbox to accommodate the 24/24.

The airbox hole needs to be dremeled out to closer match the opening on the 24/24. I used a sharpie marker with a gasket as a template to mark my airbox. Then I dremeled out the opening. Quick, easy (relatively), painless...

Regarding jetting/running rich, I'll let some of the more experienced tackle that. Maybe one of the mods can send this over to the NSM forum?
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Mon Mar 22, 2010 12:02 pm quote
Thanks for the replies.

That link is for the air cleaner and i need the carb/air box one...i'm going to try the Spaco again tonight and i'll take pics so someone in the future has them as a reference.

I was thinking that the reason i was running a little rich with the Spaco when i had it installed was that the opening was restricting airflow...anyone more experienced feel free to tell me i'm wrong.

With the Spaco 24/24, 226 pipe, stock p200 engine, the main jet that worked best was a 118. It still wasn't super smooth though. Also had to have the idle screw all the way in or it would idle rough.
Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1779
Location: Pioneer Valley Ma.
Mon Mar 22, 2010 1:00 pm quote
I did the change from a stock 20/20 to the Spaco 24/24. I have a Sito plus and a 118 jet at sea level.I believe the 20/20 was a USA requirement for emistions. There is a thread on here somwhere how to do the air box mod but you can just trace the box to engine gasket. If you dont plan to take the whole box off to dremel it ,make sure you cover the intake port

I will be doing the air filter heart mod in the near future.
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Mon Mar 22, 2010 8:57 pm quote
Did the mod tonight. I removed the box and took the dremel to it. Re-Installed and it's pretty much the same as before. I'll post pics tomorrow.

1st, I need to have the idle all the way in in order for it to stay running and even then it's a little slower than i'd like. I'm no carb expert so i'm curious why the idle isn't working properly. Would the low speed jet (not sure if that's what it's called) have something to do with this?

2nd, I got down to a 120 main and it was not running right so i probably need to go back to the 118. My neighbors were not going to be happy if i kept rippin up and down the street so i had to call it a night. Tomorrow i'll go with a 160,BE3, and the 118 and see how it works.


What about swapping out the BE3 for a BE4? The stack that came in the Spaco was nothing close to what i've seen people running...190 BE3 122???
Veni, Vidi, Posti
px200 cutdown,px180,px150. Puch SR. Puch scooterette
Joined: 08 Apr 2009
Posts: 5109
Location: west aus
Mon Mar 22, 2010 9:42 pm quote
idle 55/160

main be3--118


should do it


dunno whats goin on with the idle screw



stock pipe is the smoothest you can get ?
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Mon Mar 22, 2010 10:00 pm quote
I'll have to check my idle jet.

When i turn the mixture all the way in the engine starts to rev up. But only when the mixture screw is almost completely in. This makes me think i'm idling too lean and need to richen the idle jet.....not sure if that makes sense....it's getting late here
Veni, Vidi, Posti
px200 cutdown,px180,px150. Puch SR. Puch scooterette
Joined: 08 Apr 2009
Posts: 5109
Location: west aus
Mon Mar 22, 2010 10:16 pm quote
get it to idle rich with the mix screw till it stalls after one or two minutes of warm idling with idle backed out (from fouling)


then screw in you idle screw just a tad so it still idles when a bit rich






least thats my method
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Tue Mar 23, 2010 9:55 pm quote
Problem solved! Fixed!



I was talking to Hotrod Al about an adjustable jet and discussing my problem and we were just working out the physics of how the carb works...

does the idle screw move the slide back and forth...yeah

it only idles when the idle screw is all the way in....yeah

that's probably because when the idle screw is all the way in the main jet is providing the fuel. you probably have some blockage in the idle or idle passage.

Major problem was that there was some sort of blockage or slight blockage of the idle jet. I tore the carb down and blasted the passage from the idle to the main jet every way possible with carb cleaner

I ended up with 55/160 idle, 160 BE3 118 stack and also opened up the airbox (pics will be posted). This ran great, and i could set the idle at about 1 1/2 out. I warmed it up and it was a touch rich at WOT so i opted to drill out the air cleaner above the jets and that was the perfect touch.

Top speed with the 226 hotwing and a 20/20 carb on a downhill was 62. Today i hit 78! GPS via speedometer iphone app. Also checked max speed on a flat stretch and hit 65 before i had to back off.

Tomorrow i'll take it to work in the AM and give it the test on my big hill climb...about 3 miles up of steady grade. I could hold 45 stock.....

Update on the hill in the AM.

Check out 226 website soon for pics and a vid of my rig...1980 P200E 226 Hotwing si24/24 Spaco 55/160, 160 BE3 118 4500' ASL (RENO) everything else is bone stock......for now
Veni, Vidi, Posti
px200 cutdown,px180,px150. Puch SR. Puch scooterette
Joined: 08 Apr 2009
Posts: 5109
Location: west aus
Tue Mar 23, 2010 11:45 pm quote
well thats good then


im intrested to hear how this 226 pipe pulls up hills compared to a stock pipe
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Wed Mar 24, 2010 8:56 am quote
Took her up the test hill on the way to work. Holding 52 all the way. This was max i could hit pretty much tach'd out in 3rd. I have stock gears so when i shifted to 4th i lost speed. I bet with a different 4th i could have pulled up into the high 50's !

Pretty nice improvement.
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Wed Mar 24, 2010 9:22 am quote
Here is a pic of the thick gasket that is on the bottom of the air/carb box. This is on the P200s that came with the 20/20 carbs. I don't think the ones that came with the 24/24 had them. This is in addition to the standard thin air box to case gasket. I left it on since it was on there pretty tight. Most people take it off.



This pic shows the inside of the air box with the carb removed and the carb to air box gasket removed. I used the gasket to trace the shape on the mating surface of the carb using a black sharpie. You can see in this shot and the next one the black portions around the existing oval cutout.

The shiny area is where i've started to dremel away material from the bottom edge of the airbox...eventually working a nice smooth ramp up to the top marks. I then sanded and polished everything smooth.




Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1779
Location: Pioneer Valley Ma.
Thu Mar 25, 2010 9:47 am quote
You don't really need that spacer. I took mine out when I went to a 24/24. I was told it was another US spec. Thing.
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Thu Mar 25, 2010 10:18 am quote
I know it's not needed, but nothing was leaking between the box and case so i figured it's not doing any harm that i'm aware of.
Hooked
1980 P200E
Joined: 02 Feb 2010
Posts: 192
Location: San Diego, CA
Thu Mar 25, 2010 1:51 pm quote
My P200 has the 20/20 carb and that same thick gasket. When I re-assemble my engine (everything is stock) should I keep the thick gasket in place? Should I replace it? Or leave it off altogether?


Also, this http://www.vespalabs.org/ that I see in an earlier post is genius! Looks like I wont be needing the Haynes manual for exploding diagrams anymore...just my laptop! Thanks for posting that!
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Thu Mar 25, 2010 2:24 pm quote
Take it off and then put a 24/24 on!
Hooked
81 - P200E
Joined: 07 Jan 2009
Posts: 305
Location: St Louis
Thu Mar 25, 2010 2:32 pm quote
hurleyskis wrote:
1st, I need to have the idle all the way in in order for it to stay running and even then it's a little slower than i'd like. I'm no carb expert so i'm curious why the idle isn't working properly. Would the low speed jet (not sure if that's what it's called) have something to do with this?

When I changed out my 20/20 for a 24/24 delorto/spaco, the throttle adjuster screw that goes into the airbox needed to be adjusted. If I looked right down into the carb, I saw that the slide wasn't moving when I was adjusting the idle. After I adjusted the throttle screw, it seemed to fix the issue
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Thu Mar 25, 2010 9:55 pm quote
my guess is that the throttle cable was a little tight due to the difference in the linkage and it was probably idling a little high. In that case i'd expect the idle screw would not create any movement in the slide because you're cable was already pulling the slide out of the range of the idle screw adjustment.

When you adjusted it you probably allowed the slide to return to the fully closed position, thus rendering the idle screw affective.


Just my guess.
Veni, Vidi, Posti
px200 cutdown,px180,px150. Puch SR. Puch scooterette
Joined: 08 Apr 2009
Posts: 5109
Location: west aus
Fri Mar 26, 2010 2:30 am quote
got any pics of the pipe mr ski


Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Fri Mar 26, 2010 9:33 am quote
I'll get some pics up this weekend. Got two boxes from Motorsports yesterday so i want to get that stuff on first.....

Front and Rear Bitubos
Smoked Turn Signals
Halogen Headlight
Adjustable Brake Levers
All new rubber for the carb airbox and bellows

The stock rear shock is pretty much useless so i'm looking forward to the Bitubos.
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Mon Mar 29, 2010 7:47 am quote
PICS as promised....









Veni, Vidi, Posti
px200 cutdown,px180,px150. Puch SR. Puch scooterette
Joined: 08 Apr 2009
Posts: 5109
Location: west aus
Mon Mar 29, 2010 5:39 pm quote
what a great looking bike

and can i ask did you need to modify the centre stand to fit the pipe

and also can you drain the oil without removing the pipe first



my pm20 pipe is gone swapped it for this rack and leather top box



Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1779
Location: Pioneer Valley Ma.
Mon Mar 29, 2010 5:58 pm quote
The scoot looks nice . I really like the Big B shocks. The pipe looks a bit too loud for my hood. My peeps would be hating me every morning.
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Tue Mar 30, 2010 9:11 am quote
No mods to bolt the pipe on....226 did a great job making sure of that. Fits in perfect. I'm not sure about draining the oil...haven't tried yet.

Noise....it's not that loud your peeps wouldn't mind.
Molto Verboso
1974 Rally USA 200 1980 P200e
Joined: 27 Aug 2008
Posts: 1779
Location: Pioneer Valley Ma.
Sat Apr 03, 2010 5:20 pm quote
I drilled out a couple of holes in my P's air filter heart today as previously talked about here. I also loosened up my throttle adj. a bit and tweaked my idle. The scoot is more responsive and a bit quicker then before.

I just got around to this task after swapping out my 20/20 to the Spaco 24/24.

I'm running a 118 main jet with a Sito+
Member
Joined: 10 Mar 2010
Posts: 31
Location: Reno
Thu Apr 22, 2010 2:41 pm quote
Just following up on an earlier question regarding if the pipe allowed easy access for oil change...sure does. It's a non issue nothing interferes.

After having this on a while i'm now jetted at 122 main (4500 ASL in Reno) with the 24/24 and 226 pipe. I am going to try a 125 when i get around to it.
  DoubleGood Vespa T-Shirts  
Post Reply    Forum -> Not-So-Modern
[ Time: 0.1913s ][ Queries: 55 (0.1516s) ][ Debug on ][ Thing Two ]