Pocket Bike Engines Tutorial

[Haggard]

Haggard hasn't been around here in a little while. You should introduce yourself while waiting for a reply!
Haggard RULES BTW.
I wonder what he's doing these days.

Thanks Large. Very nice compliment. I have been working real hard and have been offline also for a few months.
no longer have a fulltime job as of a month ago but have been building bikes pretty steadily.
John , The manager at PowerKing asked if i would mind moderating their forum which i have agreed to do so am spending some time there now that i've reconnected.
I will definitely be back on MB's forum daily (if possible) now and will try to catch up.
Heres a couple of my recent builds.

Haggard

 

[mark2yahu]

Hi Haggard, I realize this is an old thread, but I don't know nuthin about pocket bikes...what do you do for a clutch on one of these engines? Is it a manual?

 

[conradcliff]

Hi Haggard, I realize this is an old thread, but I don't know nuthin about pocket bikes...what do you do for a clutch on one of these engines? Is it a manual?

I don't know a lot about them either but I can tell you that they come with a centrifugal clutch and the sprockets use #25 chain and are easily purchased at a number of mini-pocket-bike stores online. Here are two for example:
http://www.minipocketrockets.com/
http://www.davesmotors.com/site/index.html

I am seriously considering one of these engines for my build..this is the one I have in mind right now, but that could easily change. I just signed up at a pocket bike forum to get there opinions.

Haggard, if you're still out there, what is your opinion about the reliability of these pocket-bike motors? I'm super curious about them.

Thanks a ton for any help!

 

[mechcd]

I would love to have a manual clutch!


My 49cc cag copy is strapped onto my GEBE
Its the exact same engine but with a bigger bore. I have a plastic pull start

we need a section or subsection for this stuff.

 

[conradcliff]

I would love to have a manual clutch!


My 49cc cag copy is strapped onto my GEBE
Its the exact same engine but with a bigger bore. I have a plastic pull start

we need a section or subsection for this stuff.

How do you feel about it's reliability? Has it given you any issues?

 

[mechcd]

I haven't had a chance to drive it around for very long. It ran really well for about 15 minutes until my gas tank fell off. I've yet to figure out a better fuel system.

Other than that, I went straight for a Bosch spark plug and a cone filter. The link shows that yours already comes with a new nifty shiny filter

When it has gas going to it, I just turn it over slowly a few times, give it a tug, and it starts up great. Not what I'm used to with weed whackers, edgers, mowers etc. The general consensus is to buy the aluminum pawl just in case the plastic one does break from "lawn mower" starting.

As far as the GEBE setup goes, it all bolted in like they were built for each other. I went with an old brake elver for a throttle though. I haven't noticed the belt slip at all. I did accidentally go full throttle (pinched) from a dead stop and managed to leave some rubber on the road and spin around in a circle with a one legged hop

 

[conradcliff]

Excellent! Thanks for the reply. It's nice to hear from someone that actually has one of these things. I'm really starting to think this is going to be what I go with. I'll probably make a thread dedicated to these engines and see who bites on it when I get a little more time.

Thanks again for the info!

 

[mechcd]

I broke my rear wheel

Today's 30 min run with a strapped down gas tank was absolutely awesome.

Then i got back and went to put 'er away when i noticed my axle was all wobbly and the cone bearings were jammed up..... Either i don't know what I'm doing or i need a new wheel

The engine itself and the GEBE stuff are holding up excellently to my abuse and shoddy bicycle components.

 

[conradcliff]

Yikes! Well luckily it didn't come apart at speed and throw you for a gravity test.
I'm getting my bike this week then I'm going to get all the measurements and start ordering!

 

[TWalker]

I broke my rear wheel

Today's 30 min run with a strapped down gas tank was absolutely awesome.

Then i got back and went to put 'er away when i noticed my axle was all wobbly and the cone bearings were jammed up..... Either i don't know what I'm doing or i need a new wheel

The engine itself and the GEBE stuff are holding up excellently to my abuse and shoddy bicycle components.

I went round and round with this problem on a chopper I built and I'm still not sure I solved it completely.

Your cones and retainer nuts will have to be tightened like you think youll never be able to get em off. Either that or get away from the coaster brake completely.

A cone wrench was a must have for me.