Dry Lake Racer

Here's the latest info on the internetscooter project. The theme now is a Dry Lake Racer and all my notes are being captured on the Vespa Labs wiki (another project I am working on). The Dry Lake Racer is more than a theme though, as I plan to race it on an actual Dry Lake, thanks to Dry Lake Racers Australia and DLRA Speed Week March 3rd-7th 2008.

Time is tight, Jeremy (fellow Vespa Labs Dry Lake Race Team member and mechanical wiz) has taken over the engine development and it looks like we are almost there...

I am doing everything else, currently I am focusing on aerodynamics, forming a tail section and underbody section with expanding foam and resin. I also have to sort out hydraulic dampers, electronic programmable ignition and a number of other things to get the scooter on the road and through the DLRA tech inspection.

The scooter will be entered in the 250cc class, we hope to get at least 100 mph (161 Km/hr), but are aiming for the current Australian record of 106.521 mph (171.429 Km/hr)... first hurdle though is to get it doing more than 0 mph...

Step one and two in fitting a KDX topend

Step 1) Make a hole in a 20mm aluminium plate


Step 2) Make sure the KDX fits in the hole

First steps in making a top-end KDX conversion. The idea is to make an adapter plate which will negate the need for aluminum welding. I inherited my dad's lathe and I think it is very fitting to put it to use to make what could be Australia's fastest Vespa.

Things are hotting up...

OK, Max (the new bub) has been great so I haven’t been idol, just erratic...

After riding to the Mountain Goat run and having a partial heat seize (due to pushing an engine I knew was not set-up right) and, subsequentially being effortlessly passed by a Gileria Runner 180 the whole way, I decided to rethink my engine direction. After a bit of research (including looking at fuel injection and Orbital’s direct injection) I decided that a Kawasaki KDX 200 top end was the best way of getting modern performance out of an old engine. Rather than being off the road for ages though, I am getting some new cases in to hack away at.


Yes 2 - 1991 (with "the" bad power valve) and another a 1996


In other news I have started the process of making the scooter more aerodynamic (plus replacing some front end bits for good measure). The first step is to replace the front guard with a smaller one (bought from SIP, unfortunately it needs some modification to fit a disc model). I also need to work out where to fit the radiator.


Headless scooter

To do the above required dismantling the whole front end and I am now faced with a whole bunch of wires that need to be reconnected… bugger it I thought, I may as well do more as I never what to remove the headset again… so on the way I have some :

* Stebel Nautilus Compact Dual-Tone, 139 dB air horns (after an incident riding Laura’s scooter).
* HID Xenon H4 head light kit (which I’ve always wanted since my spots lights failed)
* Extra wiring so that I can hook up more gadgets with easy
* Maybe some LED indicators (if I can find some flat ones)

Back on the Pinasco front, www.electrosil.com.au gave the cylinder a light hone and it came up great. With a thick base gasket it managed to get to Mt Gambier and back (over 1000km full throttle), without problems, even with a flat piston top! However, I did have issues with the exhaust stub. ANYONE FITTING AN EXHUAST TO AN ALUMINUM STUB, MAKE SURE IT IS ALWAYS TIGHT!!!! Once the wear happens, it will stop holding correctly and you’ll go through exhausts every few thousand k’s! I have resolved the issue on the dodgey cylinder with springs.


spring loading

Once I get the scoot back on the road I’ll be re-profiling the head (based on a standard head) and fitting a Mikuni 30mm carb (with autolube!). I have a new Pinasco kit on standby but I’ll see how much my current one can take as a sacrificial kit for the furtherment of science!

Max Gatland McIntosh is here...

OK a new additional project to add to the list, my new boy Max Gatland McIntosh! Born 25th Feb 2007 at 00:27am, a whopping 4.6Kg (10 pounds 2 ounces) and 55.5cm tall. (Note: new babies are normally about 3.5Kg).


Max and his first scooter... "Dad, get a life" he is thinking

For those that like the gory details...

(Warning graphic content)

Due to some concerns related to gestational diabetes (a common problem in pregnancy) the doctor didn't want Max going too much over the due date. We booked in for induction 7am Saturday 24th Feb.

The first steps in induction took longer than expected, however it seemed to trigger Laura starting naturally as well. By 12:30pm, Laura had started a combination of drip fed oxytocin and her own... very painful as it was basically a double whammy of pain.

Too much pain/contractions is also bad for the baby (as it gets squeezed without a chance to take a breather). So they throttled back the drip and let things happen naturally. By 6:30pm Laura had done her best to fight pain and we called in the big guns i.e. the epidural (after the doc checked that she was half way there at this stage - 5cm dilated).

By 10:00pm Laura was not in pain but her body was loosing strength. Nurses were rushing around making subtle suggestions that something urgently needed to happen, like calling the doc back early and wiring her up for operation! The doc came in and announced with pleasure that Laura was fully dilated and good to go with a natural birth! She just needed to push a bit and it would be all over.

Her body was getting tired, so contractions started easing off. Laura had to push as much as she could (without actually being able to feel due to the drugs) every 10 minutes, when the contraction started. By midnight we were close but not quite there.

The final leg was doc assisted (i.e. forceps), lots of tugging, blood and horrible yanking/cracking sounds. Followed by Max popping out and letting us know why it was all so hard... 4.5Kg instead of 3.5Kg!!! We had to fit him with 000 size clothes, which are normally reserved for 3 month olds!

There was some concern that the cracking noise was Max breaking a collar bone, thankfully he was OK with just a bit of bruising. Laura came out needing a bit of attention by the doctor (nothing unusual but trust me you don’t want to know) and is recovering as well as could be expected. Although it sounds (and is) painful, she will recover a lot better than a ceaser operation and today we went for a little walk with Max in the pram.


Max, Mum and Dad

We are both home now and getting Max into a routine of feeding, pooing and sleeping… which seems to come natural to him.

Pinasco 215 not designed for Long Stroke...

I worked out one reason for the power loss, it appears that although it fits fine without a base gasket (but with a bit of combustion chamber adjustment to correct the compression), the Pinasco 215 kit is not designed for long stroke.

After pulling the engine apart I have found that the piston top has flattened out. This is a sign that the piston-to-spark clearance is too small (i.e. the top of the piston is heating up too much). By measuring various bits I have found that the cylinder of the Pinasco sits ~0.5mm shorter than standard. More worrying is that the difference in spark plug depth in the head is 2mm. If the kit was designed for a 1.5mm higher piston, then I would not expect the cylinder and head to put the spark 2.5mm lower and some info I found in German seems to tell the story correctly

So I have damaged my kit a bit and will see if it can be saved or need replacing. The trick seems to be to use a standard head and adjust it for the Pinasco i.e. for standard stroke use Pinasco head (or Worb5 adjusted head), for long stroke either use base gasket or adjust a standard head (where the spark is 2mm higher).

Note: the true measurements for the above can only be done with the piston in place, since the Pinasco piston and standard piston are different (however I doubt very much that they would be as much as 2.5mm different).

Plans for the New Year

Big plans for 2007!

First up for the year is a new baby, no not a new scooter, an actual baby, a boy called Max!

In between nappy changes, I will be sorting out my Pinasco head (which needs a complete make over), new 30mm carb, building another possible race engine (if I can't make the same engine both super fast and super reliable)... hmm... ok, a very likely new race engine build. Also getting my scooter computer back underway... yes, lots of stuff that I can do at home, as I won't be going out much!

Power Shift

OK - here's why I could not get the same top speed on the open road. I think that due to having to weld up the Sito exhaust, maybe some worn rings (they have done over 20,000Km) and running it harder than it should have (cyclinder head not perfected), has caused a dramatic power shift.


Dyno Results

I dyno'd it tonight and found that I have lost around 1 Hp in a wide region before top speed of 130Km/hr. So it is a lot harder to get there, although my peak power is actually a bit more (up 0.2 Hp). If you look at the dyno results above, the area in black is the negative difference between results from July (i.e. power that I have lost) and the hatched is the power I have gained.

This is good news because it can be fixed easily with stuff I have in the pipeline already... stayed tuned kiddies!