GP460 Engine On Friction Drive

5-7,

i don't think you want to use the chuck to actually put grabing force on the starter strap.

when it starts, it'll throw the drill at your head !!

much safer to use the pawl or a socket on the flywheel nut.

or you could make a "T" bolt / strap by putting a bolt thru a piece of flat stock, then 2 bolts protruding from the top flat "strap" to engage both sides of the "T" bar that Glen made.

make sense ?
steve
 
Okay Steve, it makes sense.

I could cut a flat plate, install a centered bolt and two more holes at the end. Then I bolt the plate onto the flywheel.

Or I could do what Ed has been doing.

FYI, after turning the flywheel easily by hand, it's not because of the higher compression that I'm having difficulty yanking the pullstart. It's because this modified pullstart is a bad design for this engine.:geek:
 
well not exactly, how would you disengage that quickly ?

what i had in mind was a bolt to mount in the cordless chuck with a flat stock "T" plate, the 2 outrider bolts would engage on either side of Glen's plate and just be drawn off as it starts.

sorry to hear that the pullstart mod is a dud.

steve
 
Steve, it will never actually throw the drill at ya, I used a socket on the bolt, when it started, it'd spin the drill with the motor, and then you just pop it off. (The drill can free wheel) If the chuck is not tight on there you'd be fine, but something better to hold on would be the right way to do it.
 
That's right guys. It's a high-speed drill and freewheels when power is stopped.:unsure:

Went to Sears, got the 3/8" socket adaptor, hooked up the cordless drill and...

nada. Hard to spin, cordless drill's clutch engaged and disengaged, engine won't start.

Hooked up a regular drill, spun that sucker over and over,,,

STILL nada.

Looking for the original pullstart assembly now.

Might swap in a new 460 engine just to see.

Well at least I changed the back tire.:giggle:
 
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Well, if you got good spin and no start, must be something else. Check spark and fuel :)

Also make sure it was spinning the right direction?
 
Ed, it started last week and for a few seconds yesterday.

Engine pullstarts clockwise and the tire spins CCW.

I have a spare engine so I'll swap in the CDI before replacing the entire motor.

I ordered a stock 460 pullstart assembly from DDM. Lemme start it with this first then go from there.

Also ordered two .005" copper base gaskets for the stock 460 engine. This should bump compression to 13:1 so I can Use the same fuel:eek:il ratio on both engines.
 
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It's Alive!

While waiting for parts to arrive, I spun the flywheel again with an electric drill and 12mm socket.

STILL no start, so I reworked another modified pullstart assembly and bolted it onto the high-compression 460 engine. I mounted the pullstart so the handle faced up, 90 degrees off what I had previously installed it.

In three pulls the engine came to life!

After a 10-minute ride in the park tonight, the throttle was out of adjustment, the air cleaner fell off and the rear engagement bottom bolt went missing.

However, in that time I learned that the engine could be made to idle smoothly and at a low rpm. The pocketbike clutch engaged VERY well so far, but I was unable to get to screaming rpm.

I installed a correct air cleaner, adjusted idle and stabilized the rear engagement support.

If "The Iron Dragonn" behaves, I'll ride it six miles to work tomorrow. That's over 12,100rpm at 40mph.:giggle:

The myth that 460 engines cannot be harnessed by friction drive has been dispelled. This one has over 5hp and purrs like a kitten at low rpm, with a 1.25" friction roller.
 
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this is great news, post up when you get to work on it.

my concern is what happens at the power transition at about 20-25mph.

if it stays hooked there at 1/2+ throttle and crossing 11,000rpm you have harnessed "the dragon"

good luck,
steve
 
The GP460 has a lot of power because the torque holds up at high rpm,not because the torque is much higher than an engine of similar displacement.Therefore the notion that friction drive can't handle this type of engine is erroneous,since this is a matter of torque,not rpm.But It takes a small roller,1.25" at 10k corresponds to 37.5 mph.Wether that has any effect on the max. torque that can be transmitted is uncertain,it might to some extent, but I don't think it would amount to much.
 
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