Pocket Bike Engine Project

I agree, the Tanakas are so sweet I am spoiled forever against any other engines.

Join Dax Friction Drive Fan Club please! I featured your bike.

I found this for you. Privee Production small-company built direct bolt on stem and bar combo, bolts onto triple tree fork clamps, not the steerer!

http://sadpanda.us/images/1172180-S6XAHK5.jpg

lowracer said:

Today I got all p'd off @ the Cag engine & am done with them for good.
The pull starter rope broke (again) & it vibrates too much (into my seat).
I installed the Tanaka 40 & rode it around.....ahhhhh such refined bliss.
I boxed up the cag with the two others I've accumulated & wont be mounting them ever again. I ordered a Tanaka 33 (had one, sold it on a bike, but loved it) & will either mount it to the front of 'The Beast' or to the back of 'The Banshee'...Here is the latest pic
-Lowracer-

Click to expand...

That's ok. FB can be annoying so I don't blame you. It's fun for me though.

I, too, gave up on the Cag engines after replacing the piston and cylinder on my GT50R after the Opti2 ate it up. Then the clutch springs broke (it is still new after a year - less than 5 miles). The friction drive ate my armadillo tires too fast, so I put on chain drive. The chain promptly broke. The head started leaking even after beefing up the head bolts. Boxed it up this spring and went back to my 2005 Golden Eagle with the 25.4 cc Komatsu. I would guess it has about 2000 miles on it after 7 years and runs like new. I know Golden Eagle stands by the Tanaka engine.

What more can I add? You are spot on. My next will be a 4stroke with belt drive only. More than likely the Golden Eagle 4 stroke Subaru on bikeengines.com - Good luck with the friction drive (I do not like what they do even on a wet road, let alone raining, big mess).

I'm also in the process of giving up on my cag engine. Seems like there is too much spitting out of it and it is very loud and vibrates lol. The thing is I just don't have the money to buy a good engine now (I wish I never spent over $150 in the cag engine plus parts on it in the first place). For that price, that equals to a good engine except the costs will stop adding up because no parts need to be replaced. So in the long rung a Tanaka might be cheaper.

While my CAG engine is reliable in terms of piston and cylinder and everything else... The only problem is the spring snapping one and that makes a huge difference in riding. I recently snapped a spring (finally) midway home and pedaling was hard because I have a chain drive with a gearbox so it took twice the effort to pedal.

That is the only thing that I'm frustrated about and it's a major problem. Stalling out of know-where as a result of the spring getting stuck in the bell is not cool. Then you have to take out the gear box and take that spring out to let it spin freely again.

If only it wasn't for the spring snapping problem, I would have otherwise kept on riding it especially if I also fixed the fuel spitting problems which I think exist on all 2 stroke engines. Infact since it's all I have for now, I will keep riding it.

For the pull start rope, I got a quality rope and used a tapered punch to punch up the edges of the copper ring on the inside where the pull start comes out of because that was one cause of ripping pull start ropes. Now, so far I have not ripped a rope with this quality rope I put on and it was cheap.

Now about your Tanaka engine tilted:

Why did you remove the flex pipe?
Does this tilt of the engine cause the carburetor to become unbalanced? And isn't that bad?
Does the Tanaka spit as much burnt fuel as the CAG engines spit the black burnt fuel?
Does burnt fuel leak at the tip of the muffler after a ride like you would see if using a CAG engine (I'm pretty sure you know what I'm talking about because especially after long rides like yours you would see this)?

Where you mounted your expansion chamber with springs, did that place where the expansion chamber attaches to the engine by sliding over a head pipe require you to seal it up? Does it leak there?
Does the expansion chamber pipe slide in with a tight fit or did it slide in with a little play when sliding it onto the head pipe?
What did you use to seal it up? (I would suppose it would seal by itself if it was a tight fit where the exhaust pipe had to be pushed onto the head pipe.)

very good thread! have just spent the past hour or so reading through it. i'm planning on building my first motor assisted bicycle using a standard cag and after reading this i think i'll go with a similar setup using belt and rim to rim just wondering if i could do it on the rear wheel or is front easier?