Scooter’s First Check Up
Posted by Stephen on
September 27, 2008

So this week, Scooter made it to 1000 KM’s which signalled that it was time to take him in for his break in tune up. The Yamaha C3 doesn’t require a lot of maintenance, but the first service is usually important to make sure that everything is tight and working properly. I took him in this past Wednesday during that ugly patch of weather that we had and just picked him up today. In addition to the usual service stuff, I also asked the shop to throw in some performance variator weights. I got these from a group buy on a site called C3Rider. The Dr. Pulley Slider Weights are lighter than the original weights (4g vs 6g) and are said to improve acceleration and top end speed due to their unique design. For $25 bucks plus shipping, why not.
The Ride Home…
I’ve been riding my scooter pretty much totally stock for the past three months. Except for an oil change at 600KM to Motul 5100 motor oil, I’ve done nothing to improve its performance. At the same time, I also refreshed the final drive oil using stock Yamaha Gear Oil. Although the scooter did seem smoother after swapping out the totally silvery crap that leaked out of my engine, there was no improvement in top speed or climbing performance.
After rolling out of the parking lot, I noticed immediately that the acceleration was different. Before, it would slowly take off and accelerate evenly. After the service and the change to the Dr. Pulley 4 gram slider weights, the scooter now accelerates just a little slower, but then takes off like a rocket after about 10 KM/h. You can really feel the scooter take off. Since there is so little horsepower in the 49cc engine, any changes are immediately noticeable and this was definitely noticeable.
Other Performance Increases…
Besides the change in the acceleration, the change in weights have improved mid range power and top end speed. The 10% grade hill that I have to ride up to get home would normally rob me of power quickly and drop my speed to a lowly 30KM/h. With the new pulleys, the speed drops very slowly and bottoms out at 35KM/h in the steepest part of the hill.
On flats, after the initial acceleration and take off, Scooter willingly, and smoothly, makes his way up to 63KM/h which is somewhere just over the 60KM/h mark and right before the Yamaha logo on a Canadian Spedometer. I have also noticed that on downhill slopes, the rev limiter no longer kicks in as quickly nor as harshly. I have yet to find the limit so I’ll report back when I can get a good downhill run.
The mid range is very usable, allowing me to easily surge with traffic and keep up smoothly with the twist of the throttle. I am really liking the results of this quick and easy $25.00 upgrade.
What About The Restriction?
The Yamaha C3 does have a washer that restricts top speed slightly at the expense of acceleration and mid range speed. Esentially, it makes the belt ride up on the variator a little higher, taking away a lower gear, while giving you back a higher gear. Since I’m really loving the way that it is driving right now, especially in the mid range, I don’t think I’ll be removing that washer anytime soon. Even the guy who discovered this modification decided to put the washer back in likely because he felt that it was way more driveable with it in. I’m sure that in flatter locations, this mod would be nice.
Any Other Mods Coming Up?
I do want to pick up a new exhaust for it so that it makes a bit more noise in traffic instead of running silent and freaking out people at crosswalks. I’m still trying to find a good one that I can buy immediately, instead of having to wait 5 weeks for it to show up. I haven’t really been able to find any good information on what sort of performance increases there are from this upgrade though. Hopefully someone with experience can leave a comment here for me.
The other thing that I’ll want to do is switch to a proper street tire to reduce rolling resistance. Most of the ones that I’ve seen are also a bit taller, so they should improve the top speed of the scooter, without screwing up the mid range. I’m all for more top speed, but I won’t do it if it screws up my hill climbing. Not to mention, the taller profile should also give me a couple more inches of clearance so I can drop a knee without scraping the center stand, which I’ve done quite a few times already. Scary.






Hey Stephen! Thank you for showing me the proper way to reply to your site. I’m going to call my dealer in the A.M. about having the recall done. I surely hate to, In 1400 miles, Except for the panel that covers the sparkplug access hole disappearing, I’ve had zero problems. I wonder how many miles were on the C3 that developed the con rod cracks and sudden stopage , And what kind of maintenance it got? (Man! That just isn’t a pretty sight!)Thus far all I’ve done is have that washer removed at the 600 mile service. I lost a bit of starting off power, But in the 800 miles since the power’s been coming back to almost where it was before the mod. I’ve averaged 48 mph @ 112 mpg. I’ve got a Stebel single note airhorn Half the size, and quieter (125db) than the bigger unit& an oil filled heavy duty rear shock absorber that I might as well have my dealer install while my scoots in their shop. Thanks for your messages, They’re interesting, imformative and often very funny! Blessings! Gabe
Yeah, I’m kinda worried about the recall too. A connecting rod breaking is bad juju on the road. Hopefully the last batch of 2007 Canadian C3’s are exempt. I mean, Mike and Keri did a pretty good job stress testing it with two people onboard riding it across Canada for over 4500+ KM’s.
I was having a look at how that destriction mod would help the scooter speed up, but it looks like it could also have a slightly faster belt wear, bringing the two halves of the variator closer together. I wonder if it’s not just simply breaking in the belt a little quicker for you and that non restricted C3’s will get there eventually on their own.
After riding the C3 a bit more with those 4 gram weights in, I think the clutch is actually not able to grab the extra pick up so I think my next logical mod would be a stronger clutch (not springs since that would just make the clutch grab later). It revs up, then slowly slips and grabs which seems to indicate that it’s a slipping clutch and not springs that are too weak.
Something definitely must be different with the US scoots vs. the Canadian Ones. My C3 only does 63 km/h max with the new weights. At 48MPH, that’s over 78 km/h. Most CDN C3’s are only doing 58 – 60km/h out of the box. What was your speed before derestriction?