OP
@sime66 avatar
UTC

Hooked
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
 
Hooked
@sime66 avatar
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
UTC quote
I don't think you have a thread for this scooter, Jack221, so here goes.

The WAV you sent was 4th gear, so I used the curve that went to around 7000rpm; it tallies well for expected max speed, but is a bit messy to get an accurate max power or torque.

External inline image provided by member with no explanatory text

External inline image provided by member with no explanatory text
Note the little dips in the curve

I used your old figures for the front page of GSF dyno, except changing the gear ratio for 4th; I've posted it below in case you want to change anything.

External inline image provided by member with no explanatory text

You have two results (neither particularly accurate), depending on which filter length I use (a longer length smooths it out, but loses peaks as well as troughs, so gives a lower result), I get the following:

17.71PS @ 6763RPM (4th)
18.08Nm @ 6763RPM
Max 6957RPM (4th)


External inline image provided by member with no explanatory text
Those little dips in the WAV make a big difference, so a better WAV would give a better result

or

15.91PS @ 6792RPM (4th)
16.49Nm @ 6753RPM
Max 6957RPM (4th)


External inline image provided by member with no explanatory text
Even smoothed out, you can see that a messy WAV limits the acuracy of the result

You'll get a more accurate result if you do a clean WAV of 0-max in 3rd!

Using Gear Ratio 4.71 and Tyre 1350mm you get a max speed of 119.6kph - 74.3mph.

External inline image provided by member with no explanatory text6) 119.65kph - 74mph

-------

For comparison, mine (180) in 3rd and before the detune was:

16.83PS @ 7760RPM (3rd)
16.28Nm @ 5631RPM
Max 8927.1RPM (3rd) (= 101kph - 63mph)
My max recorded GPS Speed in 4th was 116kph - 72mph





(Don't shoot me, I'm only the messenger)
⚠️ Last edited by sime66 on UTC; edited 1 time
@socalguy avatar
UTC

bodgemaster
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7129
Location: So Cal
 
bodgemaster
@socalguy avatar
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7129
Location: So Cal
UTC quote
Max 89271RPM (3rd)
OP
@sime66 avatar
UTC

Hooked
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
 
Hooked
@sime66 avatar
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
UTC quote
Yep, (photos, or it didn't happen?):

My Dyno run (clean 0-max in 3rd):

External inline image provided by member with no explanatory text

Screenshot of headcam video taken a few days later to try to get 100kph in 3rd on road, it wasn't going to do it; well past peak power (actually recorded 95kph on GPS, and 8930rpm on Tacho).

External inline image provided by member with no explanatory text

The film:

But enough about my engine, I've posted that lot before on a thread for my detune; this is for Jack's Tourer really, I posted my numbers just because we thought they should be similar.
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
Thanks for doing that. I think it seems about right, 16/17 bhp for a fourth gear run. As is usual the 3rd gear run would be higher, so could be nearer 20bhp. She will go to about 105km/h on the speedo in 3rd so probably about 7800 rpm and that is the feeling I get. No instruments on this scooter, so no idea about actual rpm or temperature and all been set up by plug and feel
(Mid rpm plug picture attached, still slightly rich).

Slightly fatter tyres on this scooter at about 1370mm but when sitting on them is less, so speed at 74mph is close enough. I have a video of a similar run from the other day, I'll try to upload it.

For an O tuned stock 200 with only a thin ring piston, SIP road II and an SI26/26 that are not original equipment, she doesn't go so bad. Not doing anything more to this scooter. Goes good, stock gearing and 4th pulls uphill. Will just be riding until there is some issue, which hopefully is a long way off.

Power curve on yours is still impressive for a tuned DR 180 kit. We're running pretty much the same port timing but I have more cc and you have a 3 port exhaust.
Forum member supplied image with no explanatory text
⚠️ Last edited by Jack221 on UTC; edited 1 time
OP
@sime66 avatar
UTC

Hooked
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
 
Hooked
@sime66 avatar
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
UTC quote
Happy to do another for 20bhp when you've recorded a 3rd gear 0-max run.
With a 200 gearbox your revs are considerably lower for same speeds, I wonder how temps would compare.

What's your jetting and ignition timing now?
Still with Vortex, no filter and bellows to frame?
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
When a scooter revs to near 8000 rpm, cruising along at 60mph doing 5500 to 6000 rpm doesn't seem to feel like quite as much. For this I think the stock gearing is well suited (and cheap). Important to keep in mind throughout the tune that the porting needs to be done to be the widest powerband, to cover the gear gaps of the stock box.

Timing non variable at 19 degrees. Seems to be ok with it so far. Might add a Kytronic but she really doesn't need it. Would save changing gear sometimes though. If I get the updated Kytronic for the 221, then the old one will go on the Tourer.

Jetting is still ongoing, its very close but waiting for some new ones to be delivered for the final tweek.

Yes, still Pinasco VRX vortex and bellows to the frame. Still not sure about the filter. Lot of dust where she lives.
OP
@sime66 avatar
UTC

Hooked
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
 
Hooked
@sime66 avatar
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
UTC quote
That was my point about the gearing; at say 65mph you're 6000rpm and I'm nearly 7000rpm.

You might try Patrick's in-box flat filter.
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
Yours is geared correctly for a higher revving 180. Much taller gearing and the gear gaps will be an issue.

I might try some of that filter in the carb box first. Where might I get the material? If it strangles the rpm or I have to drop more than one jet size, its coming straight out again though. There is more volume under the tank to do something with a filter if the carb box one fails.
OP
@sime66 avatar
UTC

Hooked
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
 
Hooked
@sime66 avatar
1984 PX(BGM187)EFL
Joined: UTC
Posts: 396
Location: Cornwall UK
UTC quote
I used this, but 200x300 is out of stock direct from RamAir at present:

https://www.ramair-filters.co.uk/shop/scooter-moped/panel-filter/ramair-universal-large-foam-pad-300-x-200-diy-make-your-own-air-filter/

...but still on Ebay, if you buy 2:

https://www.ebay.co.uk/itm/2x-RAMAIR-Air-Filter-Foam-Pad-Large-Scooter-Motorcycle-Quad/390494459170?epid=829136602&hash=item5aeb489522:g:CNEAAOSwbqpT80NE

You can get three filters out of a 200x300 £5 sheet, so it's a cheap test. I have an off-cut and template if you want to try (email an address). Or there's other stuff on Ebay.

I did remove mine, temporarily, when I was trouble-shooting problems earlier in the year, but intend to put it back and give it another go, with some reservations about surface area and volume of box (I fitted the bigger box first to help).




Shorts!! Wha? emoticon
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
Thinking about it the carb box filter just doesn't have the surface area. Would be near ok for stock but I doubt ok for much more.

Something under the tank. Still running the autolube, so not quite as much space as I would like but above the drip tray (air via the original ram air from the horn cast through the frame) and through the front seat hole is where all the air gets sucked in. Some filter sheet strategically fitted/glued near each might help. Plenty of time to think about it. The 221 engine is still in many small boxes.

Re shorts........"when in Rome"...... 8)
⬆️    About 3 years elapsed    ⬇️
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
Not updated this thread for my PX200 in a long time. Finally allowed (sort of) to go where it lives and have a fiddle with it.
All good. Started after a few kicks and the day after, passed the MOT without touching it. Yay Vespa. Sit around for ages and don't break.

After a twiddle of the mixture screw I thought it was running just how I like it........and thought I would celebrate with a video.
Temporary rev counter is just temporary. I like the stock look and feel of this one. Apart from the 20bhp.
@charlieman22 avatar
UTC

Nedminder
62 VBB1T Round Tail W/ leaner sidecar
Joined: UTC
Posts: 4076
Location: california
 
Nedminder
@charlieman22 avatar
62 VBB1T Round Tail W/ leaner sidecar
Joined: UTC
Posts: 4076
Location: california
UTC quote
Ha! ok. Pretty impressive willingness to idle there - must admit.
What carb is on this scoot?
@chandlerman avatar
UTC

Lucky
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9712
Location: Nashville

13 Days Since Last Explosion
 
Lucky
@chandlerman avatar
76 Sprint V, 63 GL, 62 VBB, 05 Stella, 66 Smallstate, 79 P200E, 66 Lammy S3
Joined: UTC
Posts: 9712
Location: Nashville

13 Days Since Last Explosion
UTC quote
charlieman22 wrote:
Ha! ok. Pretty impressive willingness to idle there - must admit.
What carb is on this scoot?
Also, what flywheel? I'm going to guess a stock 2.2Kg to carry it over compression that slowly?
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
Carb is a 26/26E with a Pinasco VRX vortex. Flywheel is stock electric start, I believe 2.3kg.

The project concept was total stock with as few go faster parts as possible but go fast. 26 carb, SIP Road II and a sport clutch. I think that's it. The rest is O tuning the original parts. Oh yeah, and a 68mm thin ring piston in the stock iron cylinder.
Will do 70mph two up, into the wind. And I like it.
@108 avatar
UTC

Ossessionato
V range 50s
Joined: UTC
Posts: 2392
 
Ossessionato
@108 avatar
V range 50s
Joined: UTC
Posts: 2392
UTC quote
Jack221 wrote:
Carb is a 26/26E with a Pinasco VRX vortex. Flywheel is stock electric start, I believe 2.3kg.

The project concept was total stock with as few go faster parts as possible but go fast. 26 carb, SIP Road II and a sport clutch. I think that's it. The rest is O tuning the original parts. Oh yeah, and a 68mm thin ring piston in the stock iron cylinder.
Will do 70mph two up, into the wind. And I like it.
Reviving a tuning thread... Clap emoticon

So great to see O tunes...
⬆️    About 4 months elapsed    ⬇️
UTC

Enthusiast
2005 Star Dlx - VMC 187ccm
Joined: UTC
Posts: 84
Location: Venezuela
 
Enthusiast
2005 Star Dlx - VMC 187ccm
Joined: UTC
Posts: 84
Location: Venezuela
UTC quote
Today id recorded to test my new config. But there is something wrong with GFS Dyno. Its getting 9290rpm in 3rd gear with my gearing (23-67) that is 115km/h. I think is taking wrong RPMs. I did 102-105km/h in 3rd with GPS, so, using the excel Spreadsheet , 104km/h (64mph) would be like 8250rpm with my gearing. That is like 1000rpm below GSF reading which can be traduced in 17hp aprox
Forum member supplied image with no explanatory text
Forum member supplied image with no explanatory text
Forum member supplied image with no explanatory text
Forum member supplied image with no explanatory text
⬆️    About 2 years elapsed    ⬇️
UTC

Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX125 and some motorbikes
Joined: UTC
Posts: 4524
Location: London UK
UTC quote
Riding my Px200 today. Hadn't been started for a few months and took 9 kicks, weird. Once warmed up it felt rich low down. Not so much but definitely not right.

Had tools with me, so carb top off to check the pilot jet. Saw it was wet on the edge of the fuel pipe, thought it was leaking, touched it with the screwdriver I was holding and it moved. Whole float top was loose. That explains that.

Drama over all fine again.
@charlieman22 avatar
UTC

Nedminder
62 VBB1T Round Tail W/ leaner sidecar
Joined: UTC
Posts: 4076
Location: california
 
Nedminder
@charlieman22 avatar
62 VBB1T Round Tail W/ leaner sidecar
Joined: UTC
Posts: 4076
Location: california
UTC quote
Always satisfying when the issue is peeled back to it's onion core, and the exact point of failure is so clearly determined.
Fixed.
It's gonna be a good Saturday.
DoubleGood Design banner

Modern Vespa is the premier site for modern Vespa and Piaggio scooters. Vespa GTS300, GTS250, GTV, GT200, LX150, LXS, ET4, ET2, MP3, Fuoco, Elettrica and more.

Buy Me A Coffee
 

Shop on Amazon with Modern Vespa

Modern Vespa is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com


All Content Copyright 2005-2024 by Modern Vespa.
All Rights Reserved.


[ Time: 0.0284s ][ Queries: 4 (0.0159s) ][ live ][ 313 ][ ThingOne ]