Pocket Bike Engine Project 3 (V Belt)

This bike was most recently setup as a DIY rear rack friction drive. I didnt care for the friction drive w/ the high powered engine (bad tire wear) & changed it to a more efficient V-Belt drivetrain. I mounting this pocket bike engine on a lightweight, strong, aluminum rear rack using 1/4" aluminum stock & some 1/2" thick rubber skateboard riser pads as motor mounts to absorb vibration. I'll probably need to flip the handlebars upside down to get more weight onto the front wheel for handling purposes. Here are some pics of the mostly completed project. Check out the cable connection I made using a brass spoke nipple & some silver/lead solder. Instead of having to solder a new end to fit into the throttle slide, I simply cut the too short 42" cable I had, cut a new brake cable to fit into the brake lever throttle controller & soldered the two cut ends into the brass spoke nipple. Works great.
-Lowracer-

 

[HeadSmess]

that lil pulley with almost no wrap doesnt slip? even when soaking wet?

id personally use an idler to get some more wrap or rub some violin bow rosin on the belt.

otherwise looks good

 

[lowracer]

HeadSmess,
The belt doesn't slip.
I have run a skateboard wheel tensioner in the past on a few of my V-Belt drive bikes, but mainly to take up excess belt & not for slippage. I do use the AX version of v-belt which is notched to allow for smaller pulley wrap angles & perhaps why I dont get any slippage.
I dont ride in the rain, so I can't answer the soaking wet question.
-Lowracer-

 

[blue 48]

how do these go compared to the ht style engines?
what size are they?

 

[professor]

Nice job Lowracer!

 

[lowracer]

blue 48,
The pocketbike engine I have is 49cc . I don't know anything about the HT 1st hand since I have never owned one. From what I read, they HT's aren't high performance engines & cant rev high. I can rev 10-11k rpm's effortlessly (have a rpm meter hooked up to bike) & can hit speeds over 50mph if I want to. When I ride civil, I get approx 150mpg's (did a test). I have 2 bikes now with the same pocket bike engines on them & bought another one (on the way).
I'm hooked.
-Lowracer-

 

[blue 48]

ok im sold the hts never let me down (one of which has about 15000 kms on it and still going well) but i like the mid frame mounting and chain drive so thatll be the issue ill have to tackle which wont be too bad

 

[lowracer]

blue 48,
I'm surprised there aren't more of these engines being done in-frame since they are fairly narrow, can be bolted down onto an engine mount using the bottom mounting holes, & run strong for only $129 w/free shipping on eBay with a clutch driver 6T pinion. I'm thinking by using a seattube mounted jackshaft setup similar to a Sick Bike Parts shift kit, this driveline would be awesome.
-Lowracer-

 

[lowracer]

I've been having expansion chamber withdrawal syndrome (ECWS) since putting on the DAX canister muffler. The little can kills the power output of the 2 stroke engne in a big way & though I thought a little de-tuning would be a good thing for a no-suspension bike, I was wrong.
I had to do quite a bit of re-engineering to get the chamber onto this rig. The engine mounts had to be moved a few inches out & required a full day of re-work.
Got it done today & I like the power...
I also flipped the handlebars, pushed the seat forward, & dropped the seat way down for center of gravity & handling.
Also added the skateboard wheel belt guide/tensioner.
-Lowracer-

 

[bideronit13]

Does it have back breaks?