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Old 12-08-2009, 12:20 PM
bairdco's Avatar
bairdco bairdco is offline
a guy who makes cool bikes
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Default Re: Engine for this bike?

i was wondering what the deal is with the PK's coming with two head gaskets. in my opinion, that seems like a band-aid fix for a design flaw. wouldn't that be more prone to leaks and head gasket failure?

if the piston hits, why didn't the makers of the PK either machine the engine properly, or else make a thicker head gasket?

with the way it's set up, where's the gain in performance? seems like if you build a higher compression motor, but then you have to scale it back to work properly, you're doing something wrong.

not to add gasoline to this burning controversy, but the performance difference between a PK and a Grubee or any other properly tuned motor is probably not even worth arguing about. you might go, what, 1 or 2 miles an hour faster with one or the other? the slower engine could offset that by getting better tires...

also, from what i've seen, the Grubee 49's come with the mount for oversized tubes, the 66's dont.

since there's no standard in bicycle frame design, the "bolts right up" argument is moot.

on a side note, i'll put my Grubee up against any other motor out there. 'cause mine goes really really fast...
Old 12-08-2009, 12:29 PM
Riding Rich Riding Rich is offline
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Location: pa
Posts: 349
Default Re: Engine for this bike?

Send me one and i'll gladly review it.
Haven't had any of the RAW Engines.

Dose it have a 23 roller cagless needle bearing on the crankshaft big end ?

That's what really impresses me about the PK.

Plus the Dome Piston and the slant head yeild a 9.4 : 1 Corrected Compression Ratio with 2 head gaskets in place.

Whats the comp ratio of the RAW ?
I'd love to have one.
But my wife cut off my spending till after Christmas.

I love all these Happy Time Engines.

When i was new to things i got sold on the Grubee cause of the Hype.
I found out that it wasn't the best.
I have heard Good things about the Raw.

Really though i think it comes down to bearings, no matter what the motor is capable of if the bearings cant handle it , the thing wont last.

Piston and head design would be #2 consideration.

Last but not least i would anaylize the porting #3.

I can tell you all about the motor bassed off these things without even running it.

If someone has even a Broken not running RAW if your willing to donate it to the cause i'll gladly take a look.
I'll send it back when i'm done.

I think we should have a sticky with a teardown of each motor.
Then everyone could make an educated descision bassed on the facts not opinions.
We all seem to favor what we own.
We all have our own opinions.
Everyone could argue indefinatly about there opinion but thats not productive.

A thread as i said for each engine with all the COMPLETE DETAILS and specifications.
Mathematically calculated and accuratly measured.
With the cad drawings to illistrate it all.
Would serve us all very well. and eliminate opinions.

The other thing to consider is the ability of the intended owner, and what chareteristics would suit the owner the best.

I would never put my wife on a bike with a PK80. wife =

More like a robin suburu.

Anyway Peac people.
Lets all help each other "THATS WHAT THIS FORUM IS ABOUT".

Gasbike / KingsMotors Ripped me off.

Pirate Cycles has gone above and beyond what i ever coulda expected for customer service.
Also they are on the EAST Coast so it take me less time to get shipment cause i'm on the east coast.

Venice Motor Bikes
I am sure someday i'll get a RAW just outta curiosity.
When i do it will come apart long before it ever sees the bike.

Now lets get back to Porting !!!!!!!!!!!!!!!!
Old 12-08-2009, 12:39 PM
Riding Rich Riding Rich is offline
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Location: pa
Posts: 349
Default Re: Engine for this bike?

Yep my grubee will go 45 MPH with a single spped 36T.
And yes i run it all the time up to 8000 rpm.

As far as the gaskets.
I working on pricing to buy some copper plate.
If i can get my hands on some i'll laser burn Exhaust Gaskets / Head Gaskets / Intake Gaskets all outta copper.

If i could off enough of them prolly would only cost a few bucks a pc.

I use .005 inch thick base gasket, so i need the height in the head gasket.
With the standard base gasket i'm sure you could get rid of 1 head gasket.
But again don't do it unless you check clearence.

Bottom line is it takes skilled engineers like myself to fix all of the inherrant chineese flaws.

From what i've seen every motor has it's quirks.

What do you expect for $100 bucks.

The learning expirence and fun involved is worth far more no matter what brand of engine you have.
Old 12-08-2009, 12:40 PM
Riding Rich Riding Rich is offline
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Location: pa
Posts: 349
Default Re: Engine for this bike?

Lets Get Back To Having Fun!!!!!!!!!!!!!!
Old 12-08-2009, 12:48 PM
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flybytaco flybytaco is offline
Metal Molding Madman
Join Date: Oct 2009
Location: seekonk MASS
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Default Re: Engine for this bike?

Originally Posted by maxsideburn View Post
so which one of the motor kits on Pirate Cycles is the PK80 that was talked about a few posts up? If that's the one with the serious power than that's what I want, I'm a heavy guy.
hey max. its the jet stealth limited edition comes in black and silver. definately a good motor i have a friend that weighs almost 300 and i let him ride my cranbrook and he was so amazed it even moved him.. 300 lb tested lol
the evader
Old 12-08-2009, 01:01 PM
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Dave31 Dave31 is offline
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Default Re: Engine for this bike?

Allright, I am shutting this one down. Thats enough of the attitude, everyone take a deep breath and cool down.
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