Tanaka PF-3300 performance upgrades? Or swap up to PF-4000? Feedback needed.

Tanaka PF-3300 vs. PF-4000


I've read hundreds of threads and probably thousands of posts on this gold mine of info we call MotoredBikes.com, but I haven't been able to find clear answers on one particular topic: the effectiveness of various performance-oriented upgrades for the Tanaka two-strokes.

I have a very new, not-even-close-to-being-broken-in PF-3300 on a GEBE mount. I have read the multiple statements about how one should accumulate 1K+ miles on the Tanakas before considering performance mods. I'm less than 5% of the way there, but since I'm going to be racking up 35 miles/day several times per week commuting to work, it won't take me long to hit 1K miles. (On that point, I strongly endorse getting a bike computer and installing it at the same time to keep track of usage and performance -- the speedo is obviously nice, but nifty extras like a daily odo and totalized odo are a great complement to an engine kit. I got a Topeak wired unit for ~$30USD and it's an amazing value at that price.)

I picked the PF-3300 over the PF-4000 using the logic that I was doing this to maximize savings vs. commuting in my truck, therefore the better baseline MPG of the 33cc was preferable. Now, of course, that I have actually starting playing around with my buzzbike I find that I'd love to have more power. Even though I know that the Tanaka will make more power once it's properly run in, I also believe that I will get better resale value on a nearly-new motor, so if I'm going to upgrade to the 40cc I should do it sooner rather than later.

Also, upgrading/tweaking/hacking everything I own is a deep-seated character trait. The reader could safely assume that I'm a charter subscriber to MAKE magazine, for example. :)

Assuming that I keep the PF-3300 through the break-in period, I'm interested in hearing about how effective various performance upgrades have proven to be for folks. Here's my list so far, please weigh in with any substantive feedback you might have on each:

Intake upgrade 1.0: high-perf carb with velocity stack intake and high-flow filter (~$100)
- looks good
- how much performance gain?
- how much MPG loss at steady cruise?
- different results for different velocity stacks and/or filters?

Example intake upgrade: http://www.sdminimotorsports.com/site/707069/product/blafk40
Example carb upgrade: http://www.sdminimotorsports.com/site/707069/product/32098

Intake upgrade 1.1: ~33cc "boost bottle" (resonator) plumbed into manifold
- mixed reviews on benefits
- probably not worth trying without first doing intake upgrade 1.0

Example: http://www.sdminimotorsports.com/site/707069/product/334-7356542

Exhaust upgrade: Expansion chamber exhaust pipe
- proven to increase performance, but how much??
- noise level increase -- any of these kits equal to stock muffler in SPL?
- VERY noticeable/flashy, may draw unwelcome attention from LEOs and/or prospective thieves (could be remedied with muffler wrap, which I might elect to apply in any case to reduce burn potential and keep heat away from engine)

Example: http://www.powerequipmentandparts.com/tanaka_power_pipes.htm

Cost to buy a new-in-box PF-4000 assuming good resale value for the PF-3300: less than $100. By way of comparison, an upgrade pack for the 33cc with hi-perf carb, intake, and exhaust would run about $250, more than a brand-new PF-4000. (I'm not considering the Tanaka 47R because I would like to keep my setup CARB-legal, and besides, I'm not sure if the GEBE kit would last very long with a 47R driving it...:))

To recap the key questions from above:

Will the carb/intake upgrade for the 33cc have about the same fuel efficiency at cruising speeds, or do I give up MPG across the board for more top-end power?
If there's an MPG decrease, how big is the hit?

Has anyone installed one of these outrageous expansion-chamber monster exhausts and gotten the SPL (sound pressure level) down to stock-equivalent levels or lower?
If so, what exhaust did you buy and why?

Thanks in advance for any and all insights.


Alpha Geek

Two-Cycle Tourist here in Asheville NC. Bikenstein and I have ridden through mountains with full touring gear from here to VIrginia, WV, Maryland and Pennsylvania several times. Ive been on a Vision Recumbent bicycle with underseat steering for ten years. in 2007 I added the GEBE Tanaka PF-2600 and Im now powered by a Tanaka PF-3300. Its a good motor in my opinion and makes strenous road cycling in the Southern Appalachian mountains one of my very favorite thing to do. Im thinking of upgrading to a PF-4000, and for belt alignment and motor-mounting related reasons am wondering if you know of the physical size of the PF-4000. I mean, do you know if it lines up the same. My concern is that installing the PF-4000 may require additional machining or mechanical modifications. I havent been able to get photos or necessary technical assistance from Tanaka. Also I cant find anyone with a PF-4000 in stock to make a firsthand evaluation. Do you have any knowledge about this? And thanks for your posts.
Ive been through a lot of work and rework to get my Bikenstein on the road, and to keep it there. IMG_6611.jpgIMG_6634.jpgIMG_6657.jpg
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When that family with 5 kids built their bicycle for 7 riders and rode it from Kentucky to Fairbanks Alaska, they didn't have as much gear as I see your carrying! No wonder your wanting a more powerful motor. I'm thinking a WRX motor with after market turbo on it. My son's is pushing 450 HP at the tires and 550 ft lbs torque last time he put it on a 4WD dyno.