#1. Don Butler 70cc Minarelli Cyl. HOT ROD SkyHawk engine with OCDT.

Grubee Inc


This add is for a 2 Party deal consisting of party #1 being Gru-Bee and party #2 being Don Butler's Speed Shop.   

Before placing your order, please send us an email confirming you have read all of the order description and fully understand all order requirements.   Ask questions first. Cancellations cost money!

NOTE:  Any Customer order cancellation for refund after the engine has been shipped to Don Butler's Speed shop will be subject to a 25% service charge.  Any cancellation of a confirmed order before shipping to Don Butler's Speed shop will result in a 10% service charge. 

Buy our famous Gru-Bee SkyHawk Gt5A-ES engine with OCDT for $200.00 as is in stock form and charged here-in.  We will then ship it to Don Butler's SPEED SHOP in Chickasha OK for his magic 70cc Minarelli high performance touch.      

After Mr. Butler completes his work, you will need to send him a Postal Money order by USPS priority mail or via PayPal for the balance due of $575.00. If going to Canada extra shipping charges would apply. 

When all done Mr. Butler will supply you with his Invoice and mailing address with Phone number.   He will guide you with break-in requirements and provide you with valuable technical guidance.  

Our SkyHawk Gt5A-ES engine includes OCDT = Over-Running Clutch Drive tool for handheld Electric starting. $36.95 value.

Includes:  HP TZ CDI red box and wire  high output ignition module: $20.00 value.   

Includes High Flux Rotor and High Voltage producing Horseshoe Magneto coil.    $29.95 value

Includes:   7 pcs engine mount shim kit:  $12.95 valve 

Includes:  USPS PRIORITY SHIPPING to Don Butler's SPEED SHOP   $22.00 value and also includes USPS PRIORITY SHIPPING to you which is another $22  value. 

 Includes:   3 Pt electrode 2 stroke spark plug.      $5.00 value 

 Includes:   46cm long rubber fuel line.  $8.00 value  

Includes:    Fuel line filter    $3.00 value     

 This high rev, high horsepower modified engine has a $125 DHL SAF clutch, installed and tuned.  Why?  Because the power this puppy makes will soon smoke and slip a standard 15 pad China Doll clutch.  NOTE: Order delay may occur if DHL is slow on clutch delivery due to qty. back log.   

Your Patience may be required but you don't pay Don Butler until the engine modifications are all done. 

Don Butler's Speed Shop is in Chickasha OK. and he will ship from his garage straight to your door. 

NOTE: You pay Don Butler directly for his work and communicate with him directly regarding questions about his workload and estimated ship times.   

Here's what he does to deserve the bargain price he charges which includes free USPS priority USA shipping > $22-dollar valve!

Step 1.  We deliver our Gru-Bee SkyHawk Gt5A-Es engine to Don's Shop.   You can check out all the salient features of our engine at our SkyHawk Gt5A-ES engine add here-in.   

Step 2.  Don completely disassembles the engine, checks and balances the CRANKSHAFT ASSY. adds 3 extra balance holes per flywheel.    The Dual Crank flywheels will have 5 holes on each side instead of 2.   This is a $125 balance job.

Step 3.  Don buys and installs a Minarelli 70cc vertical cylinder / 47mm piston and a flat reed valve.  Installed with 8M head bolts.

Step 4.  Don Butler PURCHASE ITEMS: 

(A.)  Don buys a DLH CNC billet cut manifold.   I'm guessing this cost maybe $50.   

(B.)  He buys a DLH SAF clutch that adds in another cost of approx. $125. 

(C.)  The final touch is for a CNC cut Billet head as shown in our ad picture which cost another $60.   

Step 5.  He does a porting job on the cast iron 47mm bore cylinder and checks the squish to assure 0.09 to 1.00mm.   A good porting operation is what makes this engine run like a scared deer! 

 So, what's his "Know How" and 6 hours of labor worth?   Go figure. 

Step 6.  He re-assembles and shim aligns the engine crank with new 2 stroke C fit engine bearings and new oil seals. 

Note:  (The 6202-1RS Crank Bearings are installed with their rubber seals on the outboard side and have open balls on inboard side for gas/oil mix lubrication.   

Don says Ball Bearing seals on the outboard side helps keep crankcase pressure from leaking which is one of the major problems with all China doll engines.   

Step 7.  When all done he does a run test that confirms starting and run ability with a dedicated in-house Carb and CDI.  

Step 8.  Don includes a new VM22 Knockoff Mikuni carburetor and AC in the box with your engine. 

Disclaimer:  Due to not being able to ship any carburetor which has had gas in it he is unable to pre-tune adjust it so you have to learn how to do that on your own.  If you don't understand basic mechanics, engine operation and tuning, please know you are in the wrong ballpark.  

Step. 9    In with the engine is a TZ HP CDI module made by the same factory that makes the magneto rotor and coil so all 3 items work in concert.   

A miss-matched CDI and rotor magnet is one of the reason some China engines run poorly.  

Don's Speed Shop does all the High Performance tedious technical work for you.     

This little Gru-Bee/Butler rice grinder is ready for a drop in frame when you get it.  100% Guaranteed to run when installed correctly.    

NOTE:  Using our OCDT assures you can electrically drill start this puppy instead of a heart attack pedal start.  

If you need a installation kit for this engine that includes: a gas tank, sprocket, cables, throttle, clutch lever, etc. we sell an Install-kit separately here in that includes all these items. 

Our HD axle wheel would give you a Pro-Shop installation.  Some, not all, die cast aluminum mag wheels with disc brake M5 pattern sprockets have been known to bust out the sprocket screws with this amount of engine power on some cheap wormy castings.

Check it all out by viewing all the pics. 

Please understand that engine rebuilding is not an instant process so it will take time to complete based on Don's work load and his parts inventory but rest assured it will be done in reasonable time by the most professional bike engine builder in the industry.