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Old 06-10-2015, 10:38 PM   #3 (permalink)
Cycle
EcoModding Lurker
 
Join Date: Mar 2015
Location: California
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Sorry, I forgot to include details of the engine:

- 174.5 cc fuel-injected liquid-cooled single cylinder.

- 62 mm bore x 57.8 mm stroke

- 0.37 mm deck height

- Squish area: 15.58 cc

- 11.2:1 compression ratio (OEM)
Although it'll be a bit higher due to the ceramic heat shield coating on the piston face and cylinder head, so let's say 11.3:1.

- 227.2 psi compression pressure

- gasoline engine

- maximum RPM: 9200 (OEM)
I'll be extending that to 12,000 with the new ECU and a beefed up crankshaft and connecting rod.

- Valve timing (OEM):
Intake Open 12° (BTDC) Close 35° (ABDC)
Exhaust Open 28° (BBDC) Close 8° (ATDC)
The new cam grind will do away with valve overlap. It'll roughly follow the same valve timing as what's found on the Negative Pressure Supercharging - Impulse Engine Technologies Pty Ltd - Australia site.

The documentation for this bike states a power output of 11.4 KW (~15.3 HP), but I think mine is a bit higher, given that it's always exceeded the factory-stated top speed, and would hit the rev limiter far too easily, which was the reason I geared up. I attribute the hard break-in (ala MotoMan) and the LiquiMoly Ceratec as two factors contributing to lower blow-by and thus better compression and power.

Last edited by Cycle; 06-10-2015 at 11:27 PM..
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