Introducing myself, a scooter newbie and a lifelong gearhead

[pngwen]

Hi everyone!  I just came across this website and thought I would join in on the discussion.  I am a 35 year old college professor in East TN, and I have just recently joined the ranks of scooter riders.  I bought a 49cc TaoTao-50 Scooter a few months ago and I have had a lot of fun riding it around town.  Prior to my scooter purchase I was (and still am) an avid bicyclist, so two wheeling wasn't new but doing it at speed was!

I decided I need a little more power, and I am a resolute gear head, so I set out to modifying the bike.  I put in a nice Kehin carb, deristricted the airbox, and this past weekend I installed a big bore kit.  I now have a nifty little fire breathing scooter that runs like a dream.  (and for a total investment well below $1000.00).  I've discovered in doing this just how simple and modifiable these bikes are, and so I will continue to make changes and tweaks as time goes on.

My next project is to play with the CVT.  I'm thinking about putting a high performance variator in there, and adjusting my clutch to get better uphill performance.  Most of my commute is spent in the foothills of the Appalachian mountains, so uphill is important to me.  I'll probably put in a better exhaust system on the next go around as well, given that it's just 2 bolts and 2 nuts to pull the exhaust off.

This little Chinese scooter is probably going to be my main vehicle for quite some time.

Oh yeah, and in other interests I am a computer scientist by trade.  My area of research is robotics, and so I get to spend a lot of time swinging a wrench for science as well!


Here's a pic of this weekend's rebuild.  I'm the guy on the right.  The man on the left is my buddy who wanted to learn more about engines.  He's a scooter enthusiast as well!

 

[derbiman]

Welcome aboard!!! You definately have the right platform to start with if you like pulling wrenches. Lol There is nothing wrong with the Tao Tao. It makes for a good learning experience. If you have a lot of hills where you live, I would suggest lightening the variator weights. That should increase your rpms and help your uphill speed. As for the exhaust, I would just modify the stock one. You won't get much of an increase in power with a so called performance pipe. You will be better off tweaking the CVT. your may also consider changing the contra spring which is located behind the clutch. A stiffer spring may also help with the hills.Changing the small clutch springs will only change the rpms when the clutch engages.

[90GTVert]

Nice pic. Looks like you're checking out the old cylinder beside the big bore and laughing maniacally at the thought of the power soon to be unleashed with a twist of the throttle.

[paulmohr]

Welcome to the forums. I have a dykon, but it is basically the same thing as a taotao. You don't need an expensive after market variator either. Just go with some lighter weight rollers but not too light. I think I have 7gram in mine. Some 1500 or 2000 rpm clutch springs will really bring it to life too.

You probably won't need the exhaust either, if you want it that is fine but don't spend the money because you think you need it. I don't think they make a huge deal on four strokes unless you have really worked on the internals first.

If your really handy you could make your own though. Use a long straight through style muffler for a small tractor or something and keep the diameter of the tubing small. All the research I have been doing on smaller engines says keeping the tube velocity is the most important thing. You can supposedly build a straight through design but still keep 1 or 2 psi back pressure if the diameter is correct.

[FrankenMech]

Dear professor, you look like you are having too much fun. I agree with Brent about the maniacal laughter.

Good luck with the robotics. It is a wonderful field.

[derbiman]

Also, don't forget to upjet the carb. You are going to need to get more fuel to the engine for the increased displacement.

[katastroff]

Glad to have you onboard!!!

[phil1979]

Welcome that's awesome I think you'll be quite pleased. I don't know what kit you bought but mine came with heavier rollers. I installed them for bit thinking it would help my engine run smoother as mentioned before by Paul he's totally correct I think about the weights. As far as the exhausti gained 4 mph in doing also I think it lets the engine breath which creates less stress and keeps it cooler. I ran super rich for the longest time especially with the stock exhaust my engine just did not perform well with the stock exhaust.

[pngwen]

Thanks for all the words of welcome and advice. You are right about the laughter bit. My wife took that picture right after we had finished prepping the new piston. We laid everything out to think about what this was going to do to my speed!

We upjetted the carb. A little trial and error showed that a #110 worked perfectly with the needle on its most lean setting. I also put in a #35 pilot jet. I haven't changed any instrumentation so RPM and fuel consumption were guesses, but it sounds good and has good acceleration and runs at top end just fine, so I think I have a winner.

For the gearing adjustments, my big interest in stiffening the clutch is due to the way the bike starts out now. There isn't much of a sweet spot where the bike can be power walked vs where it wants to go screaming down the road. Also, I want to smooth out the acceleration curve a bit.

I'm new to CVT servicing though. I know the basic operation theory (which I learned by disassembling mine when I first got my scooter.) I've ordered weights of various sizes to mess around with to get a feel for what they do. I have also looked at some variators that have steeper traces for the weights. They aren't too terribly pricey so I may try on a couple. I think you guys are right though, the weights are going to be the thing to make a difference.

Oh, while I'm on the topic of rebuiling, my big bore kit included a replacement oil pump. I put it on there but I couldn't see any difference between the stock oil pump and the one I put in. Does anyone know why that was included with a new cylinder and is there a difference I didn't notice?

[derbiman]

You have the power that you need. Now it is just getting it to the rear wheel. The way that you set up your cvt is as individual as every member here.It all comes down to personal preference,rider weight and terrain. You will know when you hit that sweet spot. The stock oil pump is probably about the same as the one that came in your kit.

[phil1979]

I got one as well before cracking my block I call the guy I bought it off from on eBay he told me and I could be wrong that it wouldn't make a difference. I did the same thing on my carb I jetted it to 95 then 110 then 100 then to 95 again back to 100 then to 90 with lighter rollers wow what a difference. Reason being was on a hot day less than ten miles I would notice significant drop in power intake was covered in fuel. Reason I richend up was the the fact it seemed like it was over heating as well. I finally messed around with my valves that still didn't make a lick of difference and seemed worse with a 90 jet vs 100 and then it dawned on me it was the weights. I even increased my top speed as well by lighting them up and barely no more spuddering. I ran a 60 mile round trip the other night 30 miles one way took one break each trip about ten minutes probably took me without breaks about 40 to 45 minutes one way. I'm running the exhaust a9 cam 90 jet 19mm carb with 90 jet 49/17 gears and 83cc bbk. Best run ever was 51mph but only got 47 thereafter however haven't tested since the jet and changing out the rollers I can say the other night my needle was burried but it wasnt all flat and all the hills I had no problems doing 60 kph + most of the time though I would lighten the throttle so I didn't stress out the engine.

[derbiman]

Take your time tuning your scooter because once you get it running the way you like it, you will have to find another project to work on. Lol

[pngwen]

I'm definitely taking my time tuning. Like you say, once that's done I'll have to find something else to do. That's the place where the real trouble can start