Any engine modifiers out there?

:cool:We are all blessed with many engines to choose from, in motorizing our bicycles. The more common ones are the 48cc-80cc Chinese engines, rack-mounted HONDAS/MITSUBISHIS/ROBINS/TANAKAS and a sprinkling of pocket bike engines.

I have two of each kind.:eek:

I'm wondering how many members are modifying their engines for more power and performance, in true hottrodding style. If so, let's hear your testimonials.

I'm digging into my $100 pocket bike engine with great vigor. First, I installed an advance crank key, which easily slipped onto the crankshaft. Next, I installed a DELLORTO 14/14/replica carb.

http://www.davesmotors.com/store/product871.html

I was disappointed that I had to remove the reed induction system to facilitate the carb installation.


A few days later, I found a high-performance reed system made specifically for DELLORTO carb on pocket bike engine.

http://www.davesmotors.com/store/product172.html

It bolted on easily, and I'm happy again.

I discovered that a tuned pipe would greatly enhance the pocket bike engine's power and speed. This is especially so if I were to use a brand name and model expansion chamber that had been proven on national racing tracks. For obvious reasons, I would not be able to use a lengthy tuned pipe made specifically for a pocket bike.

Since pb engines are very similar to goped engines, I reasoned that I'd be able to find a goped tuned pipe to fit my engine and bicycle.

I found Davesdiscountmotors.com online, and realized they had a LOT of goped and pocket bike performance equipment. First, I bought a "TERMINATOR X-CAN" made specifically for pb engines.

http:www.davesmotors.com/store/product1210.html

It's the size of a pack of cigarettes, and offered some performance gain. I bought one, and it would NOT bolt onto the exhaust flange, due to incorrect bolt spacing. Darn.

Next I carefully measured the exhaust port and bolt spacing. I also read and re-read the online catalog, painstakingly looking for cross-references between pocket bike engines and goped engines. I found out that the ZENOAH G62 goped engine shared similar exhaust port size and bolt spacing as my pb engine. So I bought a SIKK flange for a pb engine and an ADA billet flange for the G62 engine. Even though the SIKK was specifically made for the pb engine, its narrow flange restricted the engine's exhaust port by over 40%.:eek: Thankfully, the ADA billet flange matched the pb's port perfectly, and just needed the bolt holes enlarged to accept larger exhaust bolts.

After much time doing "spatial visualization"(like fitting upside-down puzzle parts) between available tuned pipes for goped engines and my pb engine, I WAS going to order the G62 tuned pipe. HOWEVER, since the G62 is a 62cc engine and my pb engine has 49cc, I ordered an ADA pipe that was catalogued for a 40-something cc engine.

http:www.davesmotors.com/store/product212.html


I reasoned that my ADA billet flange SHOULD match any ADA tuned pipe.

All my guesswork paid off. The G62 billet flange for the 62cc engine bolts onto my pb engine's perfectly. The 40-something cc engine's ADA tuned pipe slips perfectly into the ADA billet flange. The semicircular expansion chamber clears all obstacles, such as engine, STATON friction drive and tire. It is a very good fit, and I expect excellent midrange-top end acceleration.

IF the engine blows up, I'll rebuild, install an oversize cylinder kit and balance everything.

Let's hear about your engine mods!

Myron

that set up should run very well the reed set up is going to be the ticket!!!!
 
Right now, I'm running a Mits 2.2hp engine, ADA-1 tuned pipe and friction drive on my 26" Raleigh girlie cruiser. The pipe really opened up the top end. Previously, the Mits fell flat on its face at top end, like a governor kicked in. The problem was excessive exhaust backpressure, which the pipe eliminated. Now the Mits will rev to redline.

I just changed the spindle bearings and upsized to 1.5" roller. Low end should suffer, but at least the engine won't be screaming at 30mph.

Also prepping the 10hp(supposedly) pocket bike engine for friction drive on my Raleigh.
 
yes finaly some cag engine owners!

hey dont run the advance key! its ****!
and not even my cag engines get near 10HP
also the ports on these engines have bad timing so that needs to be fixed as well
 
Yeah, the guy I bought it from claimed he had dyno work done on the cag to show 10hp. I didn't see the dyno sheets, so it's just hearsay. I paid $160 for it and I'd be happy if the engine produced 6 hp.

What's wrong with the rocket key? I put one on my stock cag motor, along with reeds, Dellorto replica and ADA-1 tuned pipe. I haven't run that engine yet.

I'm still playing with my 2.2hp Mits engine, which I've had good results with. I need more power at the top of the hill to blast through the intersection. As soon as I downsize the roller from 1.5" to 1.375" and experiment with that, I'll move on to testing the cag motors.
 
go cag cause it will eat that silly mitsu alive lol

and the rocket key takes away top rpms and runs the motor hot hot hot

ive built 22 cag engines to date andthe rest were piston port x1 motors and goped engines. all the kits i see here on this site are junk the 80cc motors will have a tough time running against a tuned stock cag engine!
 
go cag cause it will eat that silly mitsu alive lol

and the rocket key takes away top rpms and runs the motor hot hot hot

ive built 22 cag engines to date andthe rest were piston port x1 motors and goped engines. all the kits i see here on this site are junk the 80cc motors will have a tough time running against a tuned stock cag engine!

Cagliari pocket bike engines are designed for high RPM and high performance. They feature reed induction, high compression, and require premium fuel. The Mitsubishi TLE's are utility engines, designed for low emissions, quiet/efficient operation, and long life. The Cag engine may deliver more power, but the Mitsu will be running long after the Cag as been recycled into beer cans.

I love the name "Cagliari" - I guess you're supposed to think of a fancy high performance Italian racing machine. "Chongqing" would be more appropriate, but it wouldn't conjure up those same thoughts, huh? :LOL:

Also - there are too many people here that have run their "Happy Time" kits thousands of miles to call them junk.

If you really want that much more power, buy a motorcycle. Talking trash about how your 50cc engine is better than another 50cc engine is a little "wee todd did". :p
 
the mitsu are of the same quality as the cag engine i would know as i have built them
the kits i see the engines break from over reving! a two stroke shouldnt be able to over rev! ive owned a cag engine for six years back when i was a wee lad and just recently put it on a scoot and got new rings and it runs as good as the day i got it.
and heres the bewidering part for you my cag engine is a mitsubishi!! the engine you are talking about is a piston port they have a great torque capacity but largly uneficiant in design.

so it depends on what you want a motor that has the power to go past 30 without breaking a sweat or a super quiet low profile bike.
 
the mitsu are of the same quality as the cag engine i would know as i have built them
the kits i see the engines break from over reving! a two stroke shouldnt be able to over rev!

I've worked on both too, and your eyes must be seeing the finer details in the "Cag" engine that my eyes don't. Oh, and any engine that cannot be over-revved is called "restricted". :LOL:

teamgorillaracingTGR said:
ive owned a cag engine for six years back when i was a wee lad .......
I remember when I was 18 and knew everything...... ahhhh the good old days. ;)

Seriously though - when I was a teenager, I was constantly tinkering around with mini-bikes, mopeds, old scooters, etc. (much like yourself) This is a hobby that has stuck with me my entire life. Even though I never worked as a mechanic, I do hold (an outdated) ASE Master Technician certificate. My neighbor was a mechanic and car/motorcycle nut and I learned a lot from him too. One of the things I learned from him and my father was that you never know as much as you think you do, and a little humility goes a long way.
 
Yeah, the guy I bought it from claimed he had dyno work done on the cag to show 10hp. I didn't see the dyno sheets, so it's just hearsay. I paid $160 for it and I'd be happy if the engine produced 6 hp.

What's wrong with the rocket key? I put one on my stock cag motor, along with reeds, Dellorto replica and ADA-1 tuned pipe. I haven't run that engine yet.

Do you have a picture of the motor? I know my fair share about these motors from building and racing them back in the days. A lot of people don't relize that the most important part of these motors is the clutch engagement. If the motor bogs on the bottom, tighten up you're clucth to engage at a higher rpm and you'll see a huge difference.
 
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