HP Pocket Bike Engine On Friction Drive

[Hawaii_Ed]

Well, I do have a complete, running pocket bike , can always "borrow" this weekend if you want!

One of the electric start cat-eye engines would be cool, plus they have the charging setup!

 

[5-7HEAVEN]

Electric start would be nice!

 

[Xqizid]

Does it run when you put fuel in manually?
Checking the connection where the lead attatches to the coil might be a good idea. It isnt the best setup on these motors, just a screw.

 

[5-7HEAVEN]

I'll have time to troubleshoot on Saturday.

Things to do:

Mix fuel/oil ratio to 25:1 or higher

New sparkplug BPM7A gapped at .028"

Check for spark and fuel.

 

[5-7HEAVEN]

It's Alive!!!

Hawaii Ed dropped by to check out "The Iron Maiden" and its HP pocketbike engine. His starting technique is different, being short and quick. After he adjusted the throttle for a smoother pull, the powerful engine roared to life.

Ed says it sounds MUCH more powerful than my 5hp GP460 engine which was originally on the bike.

The engine couldn't idle and Ed noticed that the Walbro carb was mounted upside-down. That meant that my carb adjustments were incorrect. When we readjusted the carb, the engine settled down to a steady rumble.

Fuel/oil mixture was a heavy 16:1 ratio. After a few minutes of running, the 25:1 gas in the reserve tank was allowed to flow into the goped tank. This will keep raising the oily mix until it stabilizes at 25:1. Later I'll experiment with a higher F/O ratio as the new engine breaks in.

It's late afternoon and cooler now. Time to test and tune at the park!

I'll then ride "The Iron Dragon" over the hills that proved to be too much for my 460 engine.

 

[Hawaii_Ed]

Sometimes a new set of eyes can see things from a new perspective

This bike is going to be insane! I have a stock pocket bike for my son, and this beast screams in comparison. If the tires stay in one piece, I bet it will best my top speed easily!

 

[5-7HEAVEN]

Thanks for dropping by, Ed.

I went for test and tune today. Even in poor tune, the pb engine climbed better than the previous GP460 engine.

However, its carb is also sensitive to adjustments, and it's a BEAR! to start.

The engine stalled a few times, and it wasn't easy starting. Two miles from home, the pb engine stalled and wouldn't start. Had to pedal home.

I pulled the ADA aluminum head to check which compression dome rested above the piston. There was no stamping onto the compression dome, so I'll just order a 13:1 dome to be safe.

 

[Hawaii_Ed]

will prob start and run better with less oil 25:1 is the break in, then 50:1 after that.

 

[TREEWK]

5-7 , I Have One Of Those Engines (52cc Big Bore Kit) Mine Has The Red Head, It Even Sounds Mean. Also Have Some Of The 49cc With Out The Big Bore Kit. When They Are In The Pocket Bikes They Have Air Shroud All The Way Around The Cylinder. After I Run Them Awhile, Seem To Have Trouble With Them. Am Wondering If The Fly Wheel Fan Cooling Only One Side Is Causing Cylinder Distortation. I Mounted A Gas Tank On It, Off A Stock 49cc And The Larger Head Melted A Hole In The Gas Tank. You Need To Check Your Head Bolts Also. Had It On A Friction Drive And Now It Is On Cvt Free Wheel Set Up. Soda Cans Would Even Work For Shroud Material. I See You Have The Aluminum Starter Cover. The Big Bore Kits Usually Have Them, More Compression Requires It, I Think. My Eng Would Like That Exhaust! Lol. . Ron

 

[5-7HEAVEN]

Thanks for your input, Ron. Maybe I'll look into the cooling shrouds.

Looks like you have quite the setups in your bikes.

What's your top speed on each bike?