It turns out that the exhaust upgrade was fairly trivial once I knew what to look for.  I ended up choosing the Jiangwayne Performance Pipe III , which according to their charts offers a roughly 45% increase in horsepower over the stock pipe and increased torque.  It’s not clear to me if that involves any other tweaking, like intakes, but I’ll take it at face value for now and try it out.  I bought the III because it seemed quieter than the other two and that’s one of the reasons I bought the C3 in the first place.

I also did a couple days with the standard 6g roller weights back in (with the Boppers on).  Definitely better than before, but not as good as the 5g weights both in acceleration and getting to top speed.  For now I’ve settled on the 5g weights, though I may revisit that decision once the new pipe is in place and I’ve got more power.

I now have a phone that’s capable of doing GPS tracking, so hopefully I’ll get a chance to do some speed tests and get a reasonably accurate measurement of how fast the bike can go with the changes I’ve made.

I ended up ordering two new sets of weights – one 5g and one 7g (again, 15x12mm to fit in the stock variator) – in order to experience first hand how they altered performance.  The 7g weights caused the scooter to bog badly – at that gear ratio, the bike simply wasn’t generating enough torque to accelerate well or hold top-end speed.  The 5g weights worked well to improve acceleration up to about 30mph; after that, the acceleration drops off  but is functional to get me up to the peg (about 44mph) on a flat surface and faster on any downhill.  The 5g weights also hold speed better when going uphill.  I now have a better understanding of why that is  from www.scootnfast.com , which has a great explanation of the dynamics of the CVT in their 2-stroke section. Basically, there is a large spring, the contra spring, that pushes the rear pulley plates back together when speed falls off, essentially “opposing” the roller weights in the variator in order to reduce (increase?) the gear ratio to adjust for speed.  Now that the front weights are lighter, this spring will push back more quickly when speed drops off, which causes the gear ratio to change more quickly and give more power for maintaining speed.  This dynamic also explains the “floaty” feeling I was getting with the 4g weights, as they were not heavy enough to oppose the contra spring and thus could not maintain top-end speed.  I’m going to order a set of 6g Dr. Pulley weights and compare those to the 5g – I should have a phone with GPS today, so I should be able to take some speed measurements.  With the 5g weights, I was able to ride to my brother’s place in Raleigh in just over 30 minutes, which is a significant improvement over my previous time.

Tires – I ended up doing quite a bit of research on this, most of which was a fruitless search for rolling resistance specifications from manufacturers.  It came down to either the Michelin Bopper or the Pirelli SL26.  I decided to go with the standard 120/90-10 Bopper on both front and rear, as someone on a forum had graded the rolling resistance on those tires as “A”.  That person was absolutely right.  With the Reggae, I felt like the bike was fighting me, especially uphill – if you got slow enough, you could actually feel the tires bumping, and when you let off the throttle, the deceleration was swift and decided.  The Boppers are quieter and during yesterday’s ride I had to use the brakes much more than normal because the bike really felt like it wanted to roll.

Side note:  Michelin, you seriously need to work on your scooter tire branding.  I was riding a Giggle with Reggaes.  Now I’m riding a Giggle with Boppers.  Not exactly the most appealing branding ever, you know?  You’ve got good tires, but I bought them in spite of the name, not because of it – not the best marketing!

So as things currently stand, I’ve:

  • removed the restrictor washer for a 4-5 mph increase in top speed
  • replaced the variator weights with 5g 15x12mm Dr. Pulley sliding roller weights for better low-end acceleration and still decent top speed
  • replaced the belt with a Malossi Kevlar belt, which eliminated a sluggish spot from 20mph to 30mph that was apparently due to belt wear
  • replaced my Michelin Reggaes with Michelin Boppers, which probably gave me 1-2mph top-end and help maintain speed.

After reading scootnfast’s site, my next task is improving/derestricting the C3’s exhaust to gain power.  I’ve seen references to a Jiangwayne pipe that appears to work, as well as some homemade modifications.  Back to the Internet!

To celebrate my third year riding my 2008 Yamaha C3, I decided to void the rest of the warranty and tune up the performance a bit.  Unfortunately, there’s a very small amount of useful information out there about the C3 (aka Giggle, aka Vox).  I’ve pieced together a good bit of information so I’m recording it here for myself and anyone else in the same position.

The most important thing to initially know about tuning up the C3 is that you must remove the restrictor washer.  Discussions of C3 performance tuning, roller weight modifications, and other changes all assume that you’ve de-restricted the scooter.  If you haven’t, the changes you make will be very confusing and not at all what you are expecting.  For example, I bought a new set of roller weights and had them put in before the restrictor had been removed.  Instead of improving performance, I got great acceleration … right up until 30mph, when the bike hit the rev limiter and wouldn’t go any faster.  Not useful. :)  After removing the restrictor washer, I tested it first with the stock roller weights, and was able to peg the speedometer going slightly downhill with ease – something I had never been able to do before.

The next step is to replace the roller weights as discussed in the movie I linked above.  The roller weights help control how fast the CVT gear ratio shifts.  Lighter weights give you better acceleration and theoretically lower top-end speed, while heavier weights slow the increase in the gear ratio, sacrificing low-end power for higher top speed.  With the C3, one of your more serious problems is slowing down when going uphill, so I believe that, in general, lighter weights are what you want.  This is especially true when you’re using the Dr. Pulley sliding roller weights, which are a different shape that gives you more top-end simply by allowing the plate to move further.

Here’s the information you really need, which took me some doing to find out: the stock roller weights on the C3 are six grams and 15mm x 12mm.  I bought a set of 16×13 4g weights that the shop had to grind down in order for them to fit in the stock variator.  The video I linked above recommends 5g weights, and I think that’s a good recommendation if you’re looking for maximum top-end speed and while retaining some improved hill-climbing performance.  My current Dr. Pulley weights are probably around 3.9g after being shaved down, and while low-end acceleration is good, high-end is somewhat lacking.  I can’t measure top-end speed at the moment as the speedometer is not useful past 40mph. My opinion on this may change after some experimentation, I’ve only ridden a few miles with the shaved 4g weights.  Also note that while the stock roller weights may not entirely wear out, after 12,000 miles mine showed serious signs of uneven wear with several weights having multiple areas that had been rubbed flat.

Finally, your tires are important.  I replaced the stock C3 tires with Michelin Reggae tires (the stock tire on the Zuma) after the stock tires wore out.  This turned out to be something of a problem – I lost 3-4mph on the top end, going from being able to hit 42-43 to being stuck around 39mph (this was before de-restricting and replacing the roller weights).  I believe that the Reggaes have a significantly higher rolling resistance, which accounts for the slower acceleration and lower top speed.  Finding tires with lower rolling resistance turns out to be another difficult problem, as many tire manufacturers don’t list the rolling resistance of the tires they sell.  This is my current line of research, and will probably end in calling the tire companies and trying to get the information directly.

One final note – working on the CVT on the C3 is trivial, as even I can do it.  Once you get the hang of it, the whole thing only takes about 10 minutes to take apart.  You need:

  • A strap wrench big enough to hold the variator in place while you get the variator bolt off (see the video)
  • 10mm, 8mm, and 17mm sockets and a socket wrench with an extender that’s at least four inches
  • 5mm Allen wrench (hex wrench) to remove the kick starter

The hardest part is getting the variator bolt off – I had to use a length of PVC pipe to give myself enough leverage to get that 17mm bolt off, and it took me a few minutes to get the strap wrench set properly to allow that leverage to be used.

My next step will be to order a set of 5g 15×12 Dr. Pulley weights and compare those to the shaved 4g ones I have in there now.  After that, I should have the tire research finished and a new set of tires on order.  With those upgrades in place, I should be close to 50mph as my top speed while retaining the C3’s 115mpg fuel economy.  Then, maybe, I’ll look into a new pipe.

A Fun Scenario

December 29, 2010

First, read the legal commentary and follow his links as well.

Now consider how spyware is generally installed.  A user is enticed into downloading a program, and along with this program comes a spyware program.  It’s marginally legal – the necessary text is in the EULA – but people generally don’t know they are installing it, and don’t want it.

Now, consider the Ninth Circuit’s decision in MDY v. Blizzard.  Circumventing a “technological measure” that protects a copyrighted work violates the DMCA.  That means that a spyware distributor could argue that using rootkit-like techniques to protect their software from being “tampered with” is a “technological measure” to protect their copyright.  If the rootkit-as-DMCA-technological-measure argument is successful …  presto, you have the perfect storm: spyware that leaves you legally liable for copyright violations if you remove it or disable it.

And the best part: how would the spyware owners know who you are in order to sue you?  Because their software goes through all your files and watches your internet traffic, all on the up-and-up because you agreed to the EULA.

Do you own your computer, or don’t you?  The line is becoming increasingly blurry in the commercial software world.

Yanking the Leash

July 29, 2010

So, Modern Warfare 2 players, how does that DRM leash feel when Valve pulls on it?  Unfortunately, Rock Paper Shotgun got the headline wrong – this wasn’t a goof.  It’s not an accident.  It is the direct result of Valve’s decision to prioritize their DRM software over their customers.

Also, note Valve’s policy on this sort of banning.  There is no appeal, no recourse, no discussion.  Valve, sometimes, will rescind bans that they determine to be errors – that’s it.  Anyone involved in software development knows there are plenty of bugs that can escape detection for quite some time, particularly in tricky things like anti-cheat detection and DRM software.

Do you own your software, or does your software pwn you?

A Million Ways

May 11, 2010

The entire premise of DRM is that people will simply steal software that is unprotected, and that developers who don’t use DRM will not get paid for their work.

If you still believe that DRM is required for a company to survive and for software to be sold – you’re wrong.  You’re just wrong.  A million bucks says that you … are … wrong.  Valve, EA, Ubisoft, Battlefront, all the publishers that use DRM – you’re wrong.  Deal with it.  If you want to survive, start treating your customers like human beings again and provide value instead of irritating copy protection.  This bell has been rung, and you can’t undo it.

Go forth, do good things and get good games.  Even though I already own World of Goo and Lugaru HD, I’m getting the bundle for the rest – all DRM free, all native Linux games.  To do this, I’m putting off my Grim Dawn contribution and putting all $30 I have remaining to the Humble Indie Bundle.  An awesome idea guys!

As of this morning, when I checked out the bundle, they had made $445,000 in sales.  For anyone who says that Linux gamers want everything free and don’t buy things, check out the platform price differences – Linux users have paid twice as much, on average, as Windows users.  None of these games have DRM – by standard major developer logic, these developers should be getting nothing.  The games can be pirated at will, by anyone who is capable of working a mouse.  Yet 55,000 people and counting are paying.  Are you listening, Valve?  Are you listening, EA?  Are you listening, Ubisoft?  Or are you going to go out of business still trying to screw your paying customers?