Rally 200 modifications

[henri]

if it dont ring "true" its cracked somewhere , an thats gospel from a "wheeltapper&shunters" union member , junk it .H

[vespasco]

Absolutely H.
It's gotta ring true, so off with the old and on with new.

That wasn't the the main culprit tho'

My SIP Road pipe mkl is dead
It was getting so hot today, loss of power, sounded horrible, temps a little higher than usual.
It was the same as my homemade, 'stock' expansion pipe.... the internals are shot to bits.
Might be another mouse in there.
It's done well for the thrashing I've given it over the years.
It was ok when I first started this morning and I even got a digestive plug, well, more of a custard cream, a little lighter than I prefer but its ok.

So now I'm slowly getting used to the mkll. A very different pipe.
Im not so sure I like tbh
I'm not so sure I would have as much fun at traffic lights now either

I started the jetting with what I had...52/150 idle 160/ BE3/ 152mj.
I could not really tell if it was lean or rich tbh, it felt so different after years of using the mkl pipe, where I could instantly notice the change of jetting.

Everything felt so slow to pick up, in all rev ranges. Which made me think I could come down a little on the MJ.... but there was no bogging at WOT ... and not so much power going uphill or into the wind... but it was revving out clean in 2nd and 3rd.
In 4th there was little power.

But I'm feeling my timing needs an tweak, as very occasionally it would miss a beat and it's not so clean between 4000 - 5000-ish rpm, despite changing atomizers, jets etc, including a slightly opened up top holes BE3.

Then I ran out of fuel! On the way to the petrol station! Doh!
I've learnt to carry spare fuel as I don't have a fuel gauge, run on reserve all the time and not every petrol station has premium fuel, especially on nice days as they get emptied pretty quick by other 2 wheeler folk.
But Sods Law, when I don't carry my spare 1 litre of fuel (in an old 2T bottle) in my toolbox I ran out on the way to the pumps, but only 1 mile away so not so bad and I was outside a house where I'd previously done some work so knocked on their door and asked to leave it in their garden, safe n outta sight. I'm not leaving the vespa on the side of the road unattended and I don't do push if I can help it. Then I managed to get a lift to the fuel pumps so didn't have to walk either Thank you!

So tomorrow I need to work on the SIP road mkll, get some colour on the plug and make it fast n smooth.
See where I am with the jetting
and then change the piston.

I have a new one but it does not have the Dykes ring anymore!!
Just 2 x thin and wide rings!

I'm not so sure how all that will effect my port timings?

The piston needs changing for sure, before I put a hole in it.


Edit
For my records. I fitted the SIP mkl onto the Pinasco in April 2011 and thrashed the fudge out of it ever since.

[pxguru]

Did you try to stick with the AC140 or the AC150 you made? The AC160 seems to be too lean for yours, just going to confuse the hell out of you and jetting will be extra sensitive to the weather.

The first thing to achieve is a brown plug at WOT before fiddling with atomisers, slides or anything else. The most active jets to get a brown plug at WOT are only the MJ and AC. For the carb to work in a balanced way an AC that gives a main jet between 130 and 140 is the target.

Once you have the brown plug you can start leaning it out from there and start the fine tuning and timing.

It might go well with a white plug but you know it will blow.

btw; I have just assumed you no longer have any air leaks and less inlet timing allows it to differ from mine and Simes

[vespasco]

Further update:
I've got the pipe running well now. But it doesn't seem to have the power of the SIP mkl. More noticable in headwinds and uphill.

I've tweaked the timing back a little, it was over 20' before!. That improved the running a little. There's still a hint of mis-fire around 4000rpm. Nowhere near as bad as before.

It's now jetted, by seat of the pants and it feels and sounds good. Temps are a lot lower too and I took it for a long near WOT thrash today as it was running so sweet but only because of the backwind.
Temps never went over 260'f.... thats around 20'f lower than I would have expected...and cruising in traffic at 63mph less than half throttle and it wasn't getting too hot

I'm still using the 52/150 but am waiting for my drills to arrive so I can make that a 52/155. there's just a hint of a richness in the progression... I have another 52/140 if it's too much.

But the biggest improvement was to revert back to the stock slide... that smoothed things out straight away and also helped it rev out more...
Now, is this because it's making it leaner?
Or
Is it because it's pulling in more fuel?

I tried a 160mj and could feel it was rich and bogging...coming down to a 150 in the end.

150mj felt pretty sweet but I never plug chopped with this combination. I'm still half expecting it to be white but all chops this morning showed whitish with some custard cream/digestive.
I still can't get it brown at WOT tho'.
The B9 seems to be the right heat range.

First do some plug chops with the current combination.

Now I'm a bit more used to the mkll pipe I will try the 140AC again and keep coming down on the mj to suit it and get some chocolate on the plug

Am I living in the past and hoping to get a chocolatey plug at WOT
or is it the fuel and the oil that are cleaner at WOT?

Then a biker friend of totally confused me (yes, easily done) when I mentioned the white plugs I was having... he suggested trying 'normal' grade fuel as it has a higher flash point.
Anyone?

I'm also assuming I have no leaks. The compression test was not so bad. Everything is dry in the important areas. But I have spotted fuel in between the fins, just above the exhaust, that's not got a great seal but that normally spits out black stuff if anything. It's not from the head either although the colour of fuel looks the same.
That needs further investigation.
I had to re-torque things again which threw me for a bit when it started getting hot.

I don't actually have the 140 anymore, that's the one I drilled out to 150. When I put the 140 in everything went in slo' mo'. Which is what made me make the 150.
I'll give that 150AC another go now I now where I am with the pipe.

I've had that Pinasco kit almost 6 years now and it was second hand when I bought it! That's done pretty damn well in my books.

[pxguru]

Yeah, on the same page here, for now put in the AC150 and work from there. If it doesn't go brown at WOT you need another AC140. As said before you need the AC to give you a digestive plug at 130 to 140 MJ. No point considering any other carb adustment until this is the correct colour. Once the WOT is correct everything else you have done will be out again.

Flash points of fuel are more relevant to 4 strokes. Your issues are way bigger that this finer detail.

The black gunk round the exhaust port is "splooge" (as we said before "spooge" in American speak). You cannot do the exhaust up tight enough to get rid of it, so forget that idea. Splooge always means that your progression upto mid throttle jetting is too rich somewhere. This is a really good indicator of how you are doing with the jetting. The more sploooge the richer it is, if you are getting raw fuel then its really very rich. I always worry if there is no splooge at all, very small amount of weeping splooge after a few thousand miles is ideal. Splattered all over your flywheel cover and back of kickstart is way too much. Less splooge also means the torque at low rpm will be higher. And with only 4 gears to play with, after eating too many pies, we all need maximum torque

[vespasco]

ok.
It has been running very rich in progression and idle yes and with the tap not shutting off recently it has certainly been flooded a few times too...and some fuel spilt in the chassis when dis/assembling the fuel tank which has found it's way though the chassis and onto the gear cables near the cylinder. I'm hoping it's just that that I've noticed on the cylinder. None of this helped with my starting problems I'd been having.... too rich.

The black splooge out of the exhaust stub isn't so bad, its the signs of a fuel coloured leak that worried me. I'll clean that up some more and wait for it to dry up and clear itself now it's running better.

My flash point friend is a 4 stroker to be fair.
And I was clutching at straws hoping it was just the fuel or oil thats not showing me a brown plug.

I've also got a SIP shim around the stub too. Carlsberg export cans did not prove to be the best shims in the world after all. They didn't take too long to disintegrate. Like my brain when I'm drinking it.

I'll use what I have now as a bench mark and repeat Sundays setting up but with the AC150. I think it should be better now I have the stock slide fitted and should not take too long now I'm used to the pipe.

My drills came today but it did not have the one I wanted, a 1.55mm! doh!
But now I have the stock slide fitted I may not need to change that anyway. It started strong this afternoon on second kick, although I didn't go out for a ride. I was just curious to see if it started in 1 or 2 kicks, when it did not used to (as it was too rich)
I still have to coax the piston to just passed TDC before I kick it or the kickstart lever will just bounce back.

So, hopefully tomorrow, if the weather is good, in with the 150AC and re-jet from there and report back with a chocolatey plug

[pxguru]

If the AC150 is enough to get you down to a 140MJ for a chocolate plug at WOT, then you will probably need a richer pilot jet anyway. I wouln't go mad with your drills just yet. It will all be different once the WOT issue is sorted.

The MJ starts working at somewhere like 2,000rpm on an SI carb, so running a 150MJ is going to make a pretty rich bottom end. I am sure you will find a bit more bottom end pull, once the mid throttle is running leaner on a sub 140MJ.

[vespasco]

A chocolatey plug with a 140mj?! hahahah nice one.
I tried the 160mj (or 162mj) with the AC140 before I drilled it out.
It ran rich as hell but still the white plug

I tried the AC150 today..no joy trying to get a good plug colour
although I can get it starting to show colour. It's not quite snow white anymore but its more white than brown.
It didn't run too well on the ac150.,, maybe with a little work that could be better.

I see what you mean about it running leaner at the bottom end once I come down on the MJ and will leave the drills alone.... for now.

Ive settled on the ignition timing at 19' btdc

I went back to using the ac160, be3, 150mj with the 52/150 idle and stock slide as it runs very smooth although a bit on the rich side during progression (seat of pants, not plug colour) and starts hot n cold.

It still feels like it's lacking some power compared to the SIP mkl. Its ok if there are no hills. Good job i'm in windmill county. But a head wind doesnt help. I almost had to change into 3rd to overtake! that's unheard of!

There are a few more combinations to try but Im struggling to get a choccy plug with my smallest AC and largest MJ.
I can get a v nice plug colour at 1/4 throttle! but thats it. anything above 1/4 throttle and it gets whiter and whiter.

Maybe I should clean up and fit my delly ph28mm and blast that muddy fudster down it's throat.

I'm going to order 2 x 120AC or 140AC and play with it some more.

Im not expecting it to be easy to set up with such a small AC but will give it a go... so long as i can actually get a brown plug at WOT!

[pxguru]

It really should be running rich at WOT by then. If you get to 120AC and 140MJ and it is still not all choccy, then there really is something else wrong.

[vespasco]

Update.
What happened in the end?
Did i re-restore it?

No
I went travelling again
Yes, a few days (only) in Bhutan. Then an unexpected few years in India and Nepal. (The weather was nice) I then ended up getting married, somewhere totally different lol.

The Vespa? The Vespa was locked up, serving solitary confinement for 3 years while i was away, until i ended up selling last tear, without even having the chance to say goodbye 😥

You served me so well, the Vespa.

I remember when i gave re-birth to you back in 2009. Every single piece of your magnificent body and healthy internals had been sweetly caressed and throroughly inspected by your loving master. Then I bought you back to life again, in all your former glory, just like the God of Piaggio made you.
But this time with some enhanced internal surgery to bring you into the 21st century.
Although, unfortunately, you had a skin condition and all i could give you was a roller brush finish. But you scrubbed up well. From a distance you looked factory condition. Close up you showed signs of a good life.

I then unashamedly rode you all over UK, showing off your 'one-stomp-start' to all that dared to show interest. Proud to be able to overtake lorries with ease. Applauded by national express bus drivers for being on a motorway and never in the 'slow' lane.

You were like a wild stallion, the Vespa, let loose on motorways to occasionally be able to break the speed limit.
Making me take you out on 300km day trips, most weekends just to buy you lunch was so exciting, you little orange rascal.
You acted so young and frisky, especially at traffic lights and roundabouts when people were watching.
The exotic holiday to Morocco we had was so joyful that we ended up holidaying together for 3 months. I will never forget.
I know people looked at us strangely sometimes. They even laughed at us. But most were happy to see us, giving their open palmed blessing and a smile.
But nothing will ever break the bond we have.
Sorry Spain was wet and windy. I know how much you hate water (and soap), you dirty little jaffa cake.
And sorry i made you climb those horrible hills in the Chefchaouen.
And sorry i made you eat Stop Leak engine additive in Casablanca. My mistake.
But i always took good care of you. Gave you everything you never needed. You are still fit and healthy and ready to roar like a sheep pretending to be a jacket made from wolverines.
I'm sorry if the trips to surgery were painful. I think the dremel may have scarred you a little. But no pain, no gain.
You were something else the Vespa



*The Vespa is gender neutral 😄