DR Evolution 70cc upgrade for ET2

Here is a brief introduction to "Vespa" - my 2003 ET2. It's a 50cc 2-stroke CVT scooter I have owned since 2005. I conducted a series of upgrades on the scooter recently (See my Leo Vince SP3 exhaust upgrade thread on Modern Vespa and my struggles to get a 17.5mm Dell'orto PHVA carburetor working).

The SP3 upgrade increased the acceleration of the scooter a fair bit, and the top speed from ~37mph to ~42mph. This was after upjetting the stock 12mm Weber carb from a 76 to and 80 main jet, and lightening the rollers to 5.7 gram (included with the exhaust).

Adding the 17.5mm PHVA carb didn't really help the scooter. Overall, my conclusion has been that the 17.5mm carb is unnecessary on the 50cc stock engine, even after a modest exhaust upgrade. The engine doesn't breathe enough, in my opinion, to keep up with the more open throttle positions on the 17.5mm carb.

Following these experiences, and having become used to the power of my 200cc P200E Vespa, I decided to upgrade my ET2 from a 50cc cylinder to a 70cc. I mulled over kits for a while, but ultimately settled on the DR Evolution kit. It is a cast iron cylinder with 2 ring piston. I chose it over the Malossi and Polini cast iron options because it was cheaper, but has a reputation for being very durable. It also is tuned for more modest rpm levels according the SIP scootershop from where it was ordered - importantly, it's optimum RPM (~9000) is roughly that of the SP3 exhaust I have, so my thinking was that their intended power-bands were well matched.

Here is a shot of the DR Evolution 70cc kit (arrived incredibly fast from SIP in Germany!):

The instructions are charmingly sparse and poorly translated from the Italian manufacturer, but I read extensively online prior to the modification, and felt pretty comfortable in installing the cylinder.

The first step was to chamfer the ports in the cylinder. This means rounding the edges of the ports to reduce the likelihood of catching a ring in higher stress situations and trashing your top-end. The edges of the ports typically come from the factory VERY sharp and abrupt, and if you run your finger along them you can imagine how an expanding ring passing over the port could snag.

Here is an image of the ports before chamfering. The goal is to take a file or dremel bit and GENTLY soften the edges. People often recommend ~45 degree angle cut into the edge, no more than 1mm along the length of the bore, to create a ramp which will help the rings ride back up beyond the port without catching:

Here is an image of the ports following my dremel work:
Hopefully you can see the softer edges on the ports. I discovered, however, that getting the edges just right is very difficult, and I would not say I achieved a perfect 45 degree angle on each edge of the ports. I think the most important part is to be as consistent as possible, and avoid highs and lows within the same opening which might facilitate snagging of a ring. I recommend the slowest speed on the dremel and be careful not to nick the inside of the cylinder! Note that the edges of the ports parallel to the front and back of the cylinder are the most important, since the rings come against these edges, while they travel along the edges of the ports which run from front to back (perpendicular to the rings). Remember, the key thing here is you are NOT trying to open the ports up - you don't want to take of a ton of metal and change the port timing! All you are trying to do is soften the edges to help the rings cross the openings without incident.

The next step was to gently clear out grinding dust from the bore, then remove the pipe and old cylinder from the scooter.

Prior to installing the new kit, I prepped the piston by inserting the circlip on the left side. This is because there is very little space to work on the left side of the scooter with the engine installed (yes, I did this project without dropping the engine!). So by installing the circlip on the left side first, all I had to do was insert the piston pin through the right side and attach the right hand circlip (which is easily enough done on the right side of the scooter).

Here is the piston prepped for installation - note the green arrow indicating the circlip installed on the left side of the piston in advance (the bottom/exhaust side of the piston is marked with an etched arrow on the crown). Also note that the openings of the circlips should be toward the front or back of the piston, not up or down.

Finally, after installing the piston I lightly oiled the bore of the cylinder with 2-stroke oil, installed the base gasket for the cylinder-casing interface (also oiled), and gently worked the new cylinder into place! It was fairly easy to compress the rings and slip the cylinder on - much easier than on the P200. After installing the oiled head gasket, followed by the cylinder head, and reinstalling the exhaust pipe, the upgrade was complete!

I began with the following jetting in the 17.5mm PHVA carb for the DR70 cylinder with SP3 exhaust: 74 main jet, needle clip at 2nd notch from top, and a 34 pilot jet. So far, this jetting seems to be working beautifully - at break-in speeds (under ~42mph) the spark plug has a very good color and the scooter is responsive.

My first impressions are very favorable. This machine is FAST. I suspect it will hit 50mph on a flat pretty easily - while the top speed of the stock machine was ~37mph, it now hits 37mph almost effortless and will happily accelerate past this speed on a moderate incline. I don't know the top speed yet because I plan on gently breaking the cylinder in for about 100 miles first, but if nothing else I am very pleased with the drastic increase in low-speed power over the stock machine. It will be much better for my frequent two-up riding.

I will post back with updates on top speed and fuel economy (likely in the low 40mpg range), as well as refined jetting (if any) in the future. But for now, I will say that the DR Evo appears to be a great kit.

Motorscooter Diaries part 1 - Boston to VT and back

To take advantage of the celebrated reliability of the Vespa P-series, I embarked on a 500 mile trip, riding my 1980 P200E from Boston, MA, to northern VT and back. I spent most of my childhood growing up in central Vermont, and I am very sentimental about the country there. While in Vermont I visited scenic landmarks and friends and family near the towns of Randolph, Northfield, and the capital - Montpelier.

*note, most of the images are pretty clear and can be enlarged by clicking on them

 
View Larger Map

The trip took 6 hours each way (about 200 miles one way). Because the top speed of Old Rusty is limited to the lower 60s on a flat, I took all secondary roads and minor highways. I made about 4 stops each way to rest my hands, eat and hydrate, and refuel.

This is the longest ride I have gone on, but with a spare tire under the left cowl, a Jerrycan of spare gas, spare cables, and lots of tools, I was prepared for almost any eventuality.

I left Boston at 10am on Friday the 15th. It was a beautiful day - sunny with scattered clouds and about 84 degrees. The temperature was rather warm when stopped, but with a ventilated riding jacket I was quite comfortable once traveling above about 30mph.

The scooter all fueled up in Boston and ready to go
The route took me west out of the city through central Massachusetts.


Here is a shot of the scooter by a pretty pine forest in central Mass


Near the city, nobody paid me much mind (more than usual, anyway, on a colorful old machine like this). But once I was an hour outside the city I started getting noticed - waves from pedestrians in small towns, people in old cars honking, and plenty of waves from motorcyclists. This became particularly common once in southern New Hampshire, where Harleys were a common sight and I, meanwhile, was clearly riding from a long distance off.

When I plotted my route, I foolishly ignored topography, and was unaware that the path I was riding would lead up through the foothills of Mount Monadnock. The scooter rode the higher elevations pretty well, even without adjusting the carburettor, but there was a long stretch of road near the mountain with a posted speed limit of 50 coupled with a very steep incline. There were a few cars behind me which were unhappy. Despite slowing a few cars down, the route past Monadnock was one of the prettiest stretches of the journey, with scenic vistas of mountain farms and alpine lakes.

Here's a gorgeous shot of an old barn with the mountain peak looming in the background

And two pretty shots of the scooter crossing a high elevation lake - one with the foreground under clouds and the peak illuminated, and one with the peak under clouds and the foreground illuminated


On the other side of the mountain's foothills, I took a lunch break in the small town of Marlborough, NH. I ate at a small local gas station - cash only, regular gas only, cheese burger and fries made in front of me for $3...

Mt Monadnock behind me, the rest of the ride through NH felt long - especially once I was riding alongside the Connecticut river and could see the green hills of Vermont on the other side. But eventually I made my crossing near Springfield VT, and I was back in my childhood home state


From here, I rode one of the longest break-free stretches of the journey, but it felt a relief because I was back in VT. By this time, it was near 3pm and the sun was hot and my back quite sore. But Route 5 along the Connecticut river has a gorgeous mixture of curvy forested roads and open views of farm land - tall midsummer crops waving in the breeze along the Connecticut river with green mountains for a backdrop.

Eventually, my path branched off onto Route 12, a forested and shady road which cuts through low mountains up into the Woodstock/Quechee region. While my planned path was to cut northwest through Woodstock up through the mountains and farmland into central Vermont, I had to make a quick detour through the town of Quechee to ride across the gorge. Quechee gorge is a scenic point where the Ottauquechee River cuts deep into the hills. The town is full of tourists on a warm summer day, but the view is beautiful


The ride from Quechee northwest up through Woodstock, Barnard, and Bethel into the town of Randolph where I made my first visit to friends was very pleasant. The air was cool, and I was traveling roads I often took in my childhood. One of the wonderful things about driving through Vermont is that the scenery is constantly changing, from wild fields cut through by meandering rivers, to sugar maple forests, to farm land with cows lazily swatting flies with their tails, to pine-forested mountain roads, to the historic New England towns VT is famous for.

At last, at 4pm, 6 hours since my departure from Boston, I rolled into the town of Randolph where I went to highschool. I stopped by an old friend's house while in town to see her new baby (she was up in town visiting her parents from North Carolina).

I then continued on along Route 12 to Northfield, where I stayed overnight with one of my best friends and his wife. And my long ride was done.

In the following days, I rode the scooter back and forth between the homes of my friends in Northfield and Randolph, and my father in the capital of Montpelier. There were a number of fun adventures I went on for which I don't have photographs, including a scenic bicycle ride with my father along the Winooski river near Stowe, Vermont.

Below are a series of photos from my time on the scooter riding around the state.


While riding from Northfield to Montpelier to visit my father, my odometer turned over to 9,999.9. I figured I had better take a picture, because I wouldn't see that series of numbers again for another 90,000 miles...


The Vermont statehouse is quite a nice building. It's an interesting state, because Montpelier is so small that the governing politicians of Vermont are readily accessible - you can say hello to the governor in the bagel shop in the morning or a senator in the coffee shop just down the road


Here are some shots of Old Rusty stopped at Baker Pond, heading south from my friend's place in Northfield to Randolph. My elementary school class used to go hiking in the state park nearby


I tried to visit the parents of another of my childhood friends near Randolph, but they were not home. Nevertheless, their house has a commanding view of the valley, and I thought it was worth snapping a picture. My home used to be on the other side of the mountains visible across the valley


While I rode almost entirely on paved roads on my journey, most of the roads in Vermont are still dirt roads. To get to houses like that of my friend's parents above, I had to ride some of these paths. While less safe on two wheels, something feels more personal about old country roads like these, and the hazards of riding on gravel aside, the leisurely pace was a good fit for my slow old scooter

A Vermont country road



My last night in Vermont ended with a bonfire down at my friend's pond with a reunion of several old friends. It was nice for the Vespa to be able to attend


And finally, nearly halfway home to Boston, here is a picture of the scooter taken on the Vermont shore of the Connecticut river as I hid from the 90 degree heat


All told, I rode 500 miles on the trip, averaging about 65 miles per gallon (two fill-ups broke 70!). It was a long ride, with the return trip being particularly taxing due to high heat, a strong headwind, and severe traffic outside the city. But the scooter performed without a hitch, and didn't seize up even after long stretches of riding full-throttle. I'm confident that I could cross the continent on this machine as some have done in the past, but it is clear from the riding position and power output of the vehicle that it is not meant to be comfortable for overly long distance rides except at moderate speeds and with frequent breaks. While vintage scooterists consider this a model built for touring relative to other vintage Vespas, the riding position, wheel size, and engine displacement are all still of a design optimized for nimble urban riding.

Still, the scooter handled the task with relative ease, and I believe the route I followed would be absolutely amazing with fall foliage and cooler weather. I may yet ride to Vermont again...

I will leave with an obligatory picture of my father's puppy, Henry, taken on this trip

Disc brake conversion

This conversion was completed a while back now, but my life's been hectic lately and I'm finally getting around to posting.

What I've done: converted my P200E to have fully hydraulic front disc brakes.

Why: I've been using the old beast as a daily rider for a while now, and frequently ride two-up in various conditions from hi-speed cruising to hectic stop and go traffic. Especially when I have a passenger, the stock front drum brakes can be pretty insufficient (note: proper maintenance of the drums can keep them from being useless... if they hardly work at all for you then it's probably not the drum brake's fault, but rather the condition and adjustment of the brakes).

Here's a mostly complete list of the items used for this conversion: 20mm LML fork, 5-spoked PX hub, PX-series speedo cable, Grimeca 20mm disk brake kit, PX lower headset (to provide a mounting point for the handlebar master cylinder), Grimeca/PX handlebar master cylinder, PX hydraulic brake line, PX front mudguard (the original P200 mudguard can be easily modified to fit the bill - a slot would need to be cut into the right side of the rear of the fender to allow the hydraulic hose through).

There are so many things which need to be done to make this work. It's hard to figure out where to start my coverage of the progress.

Let's start simple: I wanted to keep my P200 looking mostly like a P200, despite the upgrade. To that end, I'm retaining the original electrics and speedo, so I want to use a P2 headset cover instead of the PX cover. The problem is that the hydraulic line from the handlebar master cylinder needs to go from outside the headset to inside the headset so it can run down through the frame to the front hub. The PX headset cover is designed for this to happen, but the P2 headset doesn't know what hit it.

To get around this, and opening must be cut in the P2 headset cover to allow the brake line into the headset.

Here is the P200 headset cover on PX lower headset with master cylinder mounted:



Here is the dremel work prior to painting the parts. Now the brake line can be attached to the master cylinder and run down into the headset!


Here are the upper and lower headsets painted and ready for assembly:



Here's the PX front mudguard all painted and ready to go on. At this point I was ready to finish assembly of the fork setup and swap it onto the scoot.




Let me just say - this was a LOT of work. And it's the little things which are so annoying: hydraulic hose doesn't fit with P2 horncrest, so that needs modifying, hydraulic hose doesn't fit through neck of frame between fork tube, so that needs to be ground open wider. PX lower headset is wider than frame so it just looks a little funky. hydraulic hose doesn't fit within P2 headset very well at all - it needs to be CRAMMED in there to fit with speedo and turn signal indicator light. The LML fork tube must be ever so slightly shorter than the P2 fork tube, because the fork bearing retainer nuts are thicker than those of the P2, and prevent the headset bolt hole from lining up with the indentation on the fork. It would work fine with the P2 bearing retainer nuts thickness-wise, but the threads on the fork are a different damn pitch!

Basically - no, the P and PX bodies are not "the same," and LML inexplicably changed very small things with the fork like the fork nut thickness and thread pitch just enough that the parts aren't "compatible".

Ultimately, I got it together. And it stops on a dime. Lovely improvement in the braking and will definitely be a much safer ride. But the effort required was quite large. I always hear that the semi-hydralic setup offers inferior performance - but I suspect they ARE a good deal in terms of the labor-results tradeoff. It probably comes down to the level of performance you demand from your brakes...

Here are some images of the grinding which is necessary to run a standard PX hydraulic hose on a MK1 P. The metal fixings on both ends of the hose are too thick to pass through the opening in the frame around the fork tube. In addition, there is a metal shield around the hose which sits at the level of this opening, to prevent the hose from getting sawed through over time with the turning of the handlebars. Because this metal shield doesn't squish, it will not move back and forth through this opening with sufficient range when the handlebars are turned.

Therefore, I needed to grind the opening wider. I felt bad, but this isn't a load-bearing zone, and makes not aesthetic difference to the scoot.

In the first pic I've drawn in red permanent marker how much I needed to grind to run the hose through. However, if you can tell from the second picture, further grinding was necessary along the extent of the opening to allow the metal-shielded hose sufficient room to move (otherwise, you literally can't turn the handlebar more than maybe 5 degrees to the right without the hose getting jammed and trapping your steering in that position).



Here is the finished product - notice further grinding was done to allow the hydraulic hose room to move without jamming the steering up:



Routing the hydraulic hose was also a chore. It passes down through the gap in the frame around the fork tube and out to the finder, then down through a hole in the back of the fender to the calipers.

The hose needs to be held in place near the pivot point of the fender to fit under the horcrest amicably (but see below). On a PX, there is a hole in the frame near the fork tube at the height of the turn signals, and a ziptie with a plug attached clips into this hole and holds the hose in place.

I didn't have a good enough drill bit to run through the thick steel to replicate this hole (which is obviously absent on a MK1 P), so I settled with a ziptie on the fork tube to hold the hose in place at roughly that height. I toyed with schnazier methods, but decided it was a minor point and would be easy to upgrade/change the ziptie approach if it turns out to be insufficient (so far so good).

As hinted above, even when this is done, the MK1 P horncast doesn't have the room for a hydraulic hose passing through - the horn leaves little room behind it, and the openings at the bottom of the horncast to fit around the fork are too small for the hydraulic hose to pass through and rotate around the fork pivot point. So, I got the dremel back out and dremeled away most of this lower lip on the horncast on the right side, giving the hose room to twist and move as the handlebars turn.

It never did fit great, but it's in there. Rubber buffers on the hose at that point still snag a bit on the horncast at times, but nothing dangerous to the handling of the scoot. I'll probably dremel it a wee bit more down the road. On the upside, this modification, like the grinding of the frame near the headset, is not visible externally, so the appearance is still intact.


At last!
Here's the finished product:


The speedo cable is mis-routed in this pic - I have since moved it between the fork and the tire, rather than around the outside.

The only remaining chore was to extend the wires for the front brake switch out of the hydraulic hose hole in the upper headset to the switch on the master cylinder. This was a relatively mild chore in the scheme of the whole project - straightforward soldering is all that is required.

Overall, after months of riding on the conversion, I am very pleased. I feel much safer in tight braking situations. My efforts to keep a fairly stock appearance have me satisfied as well - the original P200 look is simpler and more pleasing to my eyes. Overall, it's turning into a very nice looking scooter from where it started, and it now stops on a dime.

Anyone who wants to pursue this modification themselves should feel free to contact me - it should be obvious at this point that it was quite a chore. Also note, I have a sport shock mounted on the front fork. I recommend a performance shock of this level or higher (perhaps a Bitubo), because with the increased braking power comes increased front-end dive. It is both a comfort and handling consideration to have a stiffer shock with these brakes.

Autumn pumpkin picking in New England

My girlfriend and I took the P200 on a wonderful country ride today to get out of the city and pick ourselves up a pumpkin to carve for halloween.
The farm we went to was fairly commercial - they had a small grocery store selling bananas on the site. But it was one of the few places in the area which let you go into the field to pick your pumpkin, rather than just having them prepicked at a stand.

The ride was wonderful - high 60s, mostly sunny, and the leaves were really starting to near full bloom!


View Larger Map

Here's a picture of my girlfriend with the scooter at the farm:
The pumpkin patch. Look at that sky!
We found a decent little pumpkin we'd be able to carry back. Here's our catch on Old Rusty!
The clouds there were pretty interesting - their passing constantly changed the perception of the fall colors
Here are some of the beautiful fall colors we saw!

New scooter forum - ScootNewEngland

Today some friends and I officially launched a new inclusive online scooter community for New England riders - ScootNewEngland. We already have a number of members who ride and maintain modern Vespas, vintage Vespas, Hondas, Yamahas... you name it.

I'm very proud to be a part of this. Check it out!

Freeing the beast

So, here's an interesting story. The P200E has a single cylinder 200cc engine. To feed this (relatively) large engine, Piaggio provided a 24mm aperture carburetor on the machine. However, in 1980, in order to pass tighter emissions laws, Piaggio restricted the engine on the P200s by using a 20mm carburetor. The 20mm carburetor was paired with an airbox (which sits between the carb and the intake) which had an oval shaped opening into the crank area.

Now, most owners over the years swap the 20mm carb on their P200s out for a 24mm, not so much as an "upgrade" but a "return to stock". The catch is, the opening on the bottom of the 24mm carburetor into the crank area is circular. Because the 20mm carb airbox has an oval opening which is smaller than the circular opening on the 24mm carb, modification to the airbox is necessary to take advantage of the larger carb.

Basically the airbox opening blocks off part of the opening of the 24mm carb, restricting the volume of fuel/air/oil mix which can move into the crankcase at a given time.

Proper 24mm carburetor airboxes are hard to find, so the better solution is to modify the 20mm one which came on your 1980+ P200.

It just so happens that somewhere in my scooter's life it had indeed been upgraded to a 24mm carb. However, whoever did the upgrade didn't think through what they were doing and no modification was made to the airbox. So I took it upon myself to finish the job, and make my 1980 P200E a 1970s P200E. It's pretty easy. What I did was take the carb and airbox off the engine. I took the gasket which sits between the carburetor and the airbox, and positioned it as it should sit in the airbox. I then took a permanent marker, and marked the part of the airbox which was obstructing the opening on the gasket (in blue below).



I then took a dremel with a gentle grinder tip, and went to town. This took some care, because on the underside of the airbox there is a channel for oil to be pumped into the carb, and it runs near this opening. The opening of the airbox is also tapered on the underside to match up with the opening on the crankcase. I'm not sure how critical it is to try to mimic the taper when grinding the opening bigger, but I figure the fuel system is a pretty important part of the function of the engine, and wanted to do it right. So I took quite a bit of time with the grinder bit followed by a polishing bit to really machine it to match the opening of both the carb and the crankcase.

I didn't get a good shot of the underside, but I think I did a good job machining the opening to have just the right taper to it. No more restriction here!

Big things in the works

So a lot to update on since the last post. First of all, the glovebox is finished being painted:


I also got new tires in the mail for it. VERY good price on some good michelins. The previous tires were these crusty old whitewall Sava tires, and the rubber was splitting right along the transition between the white and black rubber. The new tires were a pain to get on, but a little bit of soapy water rubbed along the inner surface of the split rims helped them slide into place (I've since read that it is better to use baby powder or the like to prevent rust, but you live and learn).

So, with the glovebox mounted and the new tires on, I've got a complete P200!