Noticable by your butt dyno, or lap times. If your an Expert level rider a significant change will show in lap times.
All moot for me as my race org had a simple rule to keep costs down. "no metal may be removed form the engine internals.
A few exceptions were a 3 angle valve grind only and small amounts fro balance purposed.
They even tried to ding me for elongating the cam chain sprockets for decreeing the cams.
BTW I found the stock settings (cams) produced the most area (power) under the curve. albeit a 2 hp loss from some more aggressive settings.
But for my home track Loudon. best pull out of the corners at 6000 RPM was critical.
It was never on the dyno, definitely the butt dyno. Was running megacycle cams, 38mm flat slides, raised compression, ported head, supertrapp 2 into one and methanol fuel. This was in the early nineties so I can’t remember what l had the lobe centres dialed in at. The racing class here was open so you could do anything you wanted. the 500 was always a better bike out of the corners and top speed than the 400 4s but the chassis suspension, wheels and brakes were no match.
Interesting approach kiwigpz! It is in the same line as I did with two other bikes. I also reshaped the valve seats as shown below. The exhaust port will be widening from the valve seat up to the end of the port, so the hot exhaust gasses can keep expanding without building up pressure.
Besides the seats and ports, I removed every hump of material between the valves in the combustion chamber. This will probably feel as a contradiction because this step will lower the compression ratio. But in the earlier posted diagrams from the before and after dyno run, a 14% gain in torque over the full rpm range is visible. Also, the oil temperature dropped 10^C. In my Moto Guzzi the oil temperature even dropped 20^C.
I'm really curious to what this approach will do for the EX / GPZ!
you missed some tricks. if your looking to get max power.
1 Re cut the seats to get the maximun diameter the seat inserts will allow then cut the seat width to 1/16 use a larger valve if you need too cutting the valves does little.
Run valve clearance as low a .005 (recheck often)
Porting without a flow bench is really guess work and can backfire and things like laminar flow and turbulence cannot be determined.
I have found little more than cleaning of the worst carbuncles is all. rough cast surfaces actually flow better than polished
I'm not looking for more peak power. Hopefully the modifications wil actually make the power delivery more manageable and with that save the crank. With the EX, it will not only the exhaust that will be ported, but I'll make the intake ports also smaller in according to the Moto Man USA method.
Does anyone know how to loosen the timing chain?
I'm replacing the cylinder head and have the tensioner out but the chain will not loosen up. Camshaft brackets are out but I can't get the cams out because the chain wont let go
First off im new to these threads. I have done a search to try and find anything related to my problem but nothing rly is the same. I currently own a 2005 Ninja 500 with about 2600miles and just recently while riding down the highway it started to decrease in speed and finally cut off on me...
Hey guys, I think this is my third thread so far but
my bike has been going to 3/4 on the temp gauge on idle during stops. Just changed my oil and coolant which seems fine. I do have a manual switch for the fan installed by the previous owner but I don't knoe whether or not it's suppose to work...
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