Looking to purchase a Dyno Flywheel Axle Assembly that
is balanced to get minimum face run-out? Details below:

COMPUTER CUT-OUT, BLANCHARD GROUND TILL PARALLEL
ON BOTH SIDES, THEN WE WELD ON SPECIAL INNER HUB
AND TORQUE UP WITH DIAL INDICATOR ON FACE
TO GET MINIMUM FACE RUN-OUT.
IF ITS NOT GOOD ENOUGH,WE TAKE IT APART
AND START OVER!

Contact me to purchase:
Stan Hewitt
c 641-512-3395
hewittdyno@gmail.com
twitter.com/InertiaDyno

Here’s a dyno pull comparasion of a Chinese yellow clone motor on gas. We started with a stock engine with a stock muffler, put in 16 oz. of 10w30 oil and did a couple of dyno pulls. Engine ran very bad, sounded like a bad spark plug. As you can see by the lower dyno pull engine surged very bad due to very lean condition. Made 4.6 hp at maximum at 3000 rpm. First thing we did was remove stock muffler and replace it with a small header we got from ARC.  Really didn’t help much, engine still very lean. Drilled main jet out to .037″ and dyno again. Engine souded very strong and made big jump in horepower. We then tryed Animal springs instead of stock springs. Really didn’t do anything, in fact lost hp on top end. Went back to stock springs and stuck on large RLV header. Made a pretty good jump in hp. Ended up with large RLV header and .036″ jet. I don’t think this header will be legal for the rules that I skimmed thru very quickly but just for your infomation. I think the small header from ARC ran best with a .035″ jet.  I know A.R.C.  & J.C. Specialtys both have parts for these.
About 5400, this motor really fill off. A couple of people have told me spring pressures will make a big difference but they will not be legal!
The dyno sheet show a comparision of a bone stock engine with how we ended up with all stock parts except for jet change. Tightening valve lash settings didn’t make much differance. Ended up gogin back to .003″.  Max torque was at 3600 rpm, peak hp at 4900 after jet change.

Interested in Purchasing a Hewitt Inertia Dyno?

Call me today…

Stan Hewitt
c 641-512-3395
hewittdyno@gmail.com
twitter.com/InertiaDyno

Used on v-twin briggs engines on dirt type race cars. We made a quick change #40 chain two piece split sprocket so he can change from 3-to-1 or 4-to-1 ratio. This engine has electric start so he just hooks up battery, starts engine, turns on the data system and hits the gas. This dyno is accurate to 1/10th of a horsepower & also is a clutch dyno. Measures engagement rpm, slippage ratio and also measures where total lock-up of clutch occurs.  Interested in a Sling Shot?   Give me a ring.  Stan

2008 AXLE/FLYWHEEL ASSEMBLIES

From experience in building over 110 assemblies, we make sure these are built correctly to allow no axle keyway wear, loosening or wobbling. The flywheel is built to be used as a brake rotor. We have the outside and inside diameter cut with a CNC torch. Both sides are then ground on a Blanchard grinder so they are parallel. Then we weld on a special female type hub assembly. The axle and male hub are put together and torqued up straight using a dial indicator so that the face run-out is less than .015”. We can use any axle size from 1” to 4” including metric up to 50mm.

Normally we use 1 ¼” stress-proof steel with keyways cut only were they need to be. We never have a keyway where the bearing is going to ride. We stock axles in 1 ¼” and 1 ½” in length to 47”. We can custom make whatever you want. We can also build 40mm at a slightly higher price. We stock one-way sprag clutches and torsion shock systems and can get most sizes overnight. If you want us to ship a flywheel/axle assembly to you, we will need your zip code for a freight estimate. We use R&L Carriers since they have Tommy lift type tailgates to get the assembly to the ground and you can get it into your shop with a pallet jack. Residential deliveries cost an optional $50.00. Its best to ship to someone with a forklift or loading dock. I give a 65% discount off of list price. The flywheel will be banded on a pallet and shrink wrapped. These assemblies include high quality Japanese NTN pillow block bearings with eccentric lock collars. They are computer balanced to less than 5 grams at 500 rpm’s. There is a heavy duty sprocket hub included with a 53 tooth sprocket. If you plan on adding electric start or belt drive it is best to add that before balancing the assembly. If you are using a clutch dyno, use a 24 or 29 hp flywheel with a higher gear ratio so you aren’t so hard on your clutch. I recommend a Premier Titan clutch with yellow springs. Horsepower ratings are for 15 second dyno pulls. I highly recommend installing a flywheel so that electric start and belt drive can be added at a later date. We do sell dynos in kit form so all you do is weld it up and start using it. You will get every part with a basic blueprint. We build dynos up to 125 horsepower with multiple flywheels so you can do 3 hp up to 125 hp. Please note that for flywheels above 30 hp, I recommend 1 ½’’ to 1 ¾’’or 40mm stress-proof axles and those above 40 hp to use 1 ¾’’ or 2’’ stress-proof axles. The following are the three most common flywheels that we sell.

1.25” x 28” rated 24.16 hp. sells for $1681.42

1.50” x 28” rated 29.16 hp. sells for $1761.07

3” x 23” rated 26.5 hp sells for $1759.85

Remember this includes all the labor to do everything including the machine work, assembly, computer balancing, (3) new NTN bearings, key stock, H.D. sprocket hub, #53 sprocket, crating, banding, and put on a pallet for shipping.

Looking for a dyno that cand do engines from 4 hp up to 100 or more.   I’ve done hundreds of  Inertia Dyno’s in the U.S. and a few internationally.  Engine Builders – If you are seriously looking to improve overall performance from your engines you must utizlie this technology.  All data systems come with a S.A.E. weather correction system. Most customers order head temperature and some use a exhaust sensor in the crankcase oil to make sure engine is up to temp. Air/fuel ratio is now available as an option.  Questions?  Want to purchase? Call me…

Stan Hewitt – Owner
c 641-512-3395
hewittdyno@gmail.com
twitter.com/InertiaDyno