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[Rulg]

sometimes, i swear, i am almost the only american that knows how to tune an engine...

Anyway... i have 39.7 HP theoretical @ 175 psi @ 5K5 rpm

flame front speeds are difficult to calculate;
but just roughing it out, i would not recommend pushing the 535 past it's stock rev limit ... that's a 9cm stroke.

engines can outrun their flame fronts,
( the rev limit should be at the rpm beyond which the exhaust valve would be opening while the charge is still burning )

so idea here is a Max Power Stoich Tune;

that's how i tune, because:

1 ) i don't like wrecking engines

2 ) the fact that liquids don't compress;
is no reason to use a rich mixture to artificially increase the compression ratio, with wasted fuel.

3 ) outrunning the flame font by using a mixture too rich to fully combust to blow the flames off your exhaust valves, might keep your valves from seizing for awhile; but your not making anymore HP up there in the flat line past that, just making smog that no one appreciates, with wasted fuel...

[Rulg]

granted...39.7 HP is Theoretical...but let's shoot for 38 peak..

this is a meticulously polished chamber and crown, high test only, go at it..

i am talking breaking any sharp edges on the spark plug, with worn out 400 grit wet/dry, here...polished.

[Duke of Wybourne.]

One of the advantages that our UK models have is the under seat B.P.D.F. It helps immensely.

[Rulg]

anyone who follows this with a carb;

you can get an A/F ratio meter with an O^2 to swap in for tuning.
( 14.7 is Stoich, and you want the number to be that, or a little less )
after it is warmed up, just try to keep it above 14 if you can.. but don't go over 14.7

i do not condone exceeding the stock rev limit, so i am not going to talk about that.

[Rulg]

i don't have a RE 535 CGT yet, ( i will let you all know if that works out )

just studied the design for awhile, and need some numbers to get my virtual 535 dyno running, so i can start tweaking it up.

mainly i need:

1 ) Rocker Ratio
2 ) stock cam timing data
3 ) length of the intake runner ( from the mouth in the air box to the valve stem )
4 ) approximate exhaust length ( from the end of the pipe, with the muffler off, to the exhaust valve stem )

also see my other thread here entitled:
"535 Horse Power Upgrade ( Mono-Directional Crankcase Breather )"
i am hoping Hitchcock's picks that up, and has a product available in kit form, if the proto gives some go..

[Rulg]

One of the advantages that our UK models have is the under seat B.P.D.F. It helps immensely.

i have to ask you to de-cript the acronym ... i am new here.

[stinkwheel]

If you're going to calculate inlet pressure wave trumpet lengths, I can save you some time. You'd need to start by offsetting the rear wheel.

[Daiwiskers]

If you off set it by 5/3" you should be about right
But then you would need a 4" trumpet

[Rulg]

is "B.P.D.F" some sort of closed loop auto tune box for the ECU ? ... am i supposed to guess ?

[Rulg]

If you're going to calculate inlet pressure wave trumpet lengths, I can save you some time. You'd need to start by offsetting the rear wheel.

5/3rds and 4" intake trumpet .

i will get an MT-03, and hope someone get's something out of what i wrote here someday..