Funny but ... LOL
Seriously any plans to trim the weight a bit more
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Kinky is using a feather. Perverted is using the whole chicken
Are our crankcases cool enough?
Frits mentioned in his cooling cooling cooling post and showed some shouds and some fins explained the crankcases are also water cooled
the reason i ask is i have noticed a couple of trends.
Why because air expands when its heated.
Crankcases compression is now lower...... air heats when its compressed.
Transfers streams are directed avoid the piston crown (the crown is hot)
All very obvious i know but what is the hp drop per deg c increase of the crankcase mixture?
Frits mentioned (i think) to adequately cool the transfers would require a rad as big as the engines, would that be a bad thing and is there other ways?
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Kinky is using a feather. Perverted is using the whole chicken
Old, cast Rotax cases,make better power than CNC billet replica ones as the rough cast surface sheds heat more effectively.
Even where both are watercooled.
On the dyno the CNC cases heat fade very quickly.
Very very little transfer flow is created due to case com, except in your lawnmower,its all to do with the diffuser depression around BDC.
And there is a Catch 22 happening with the piston.
Transfer flow needs to attach to the crown to cool it, but this heat transfer affects the volumetric efficiency badly.
Cant have one without the other, but the piston simply isnt able to shed heat fast enough, just thru the ring and skirt alone to the cylinder wall.
In a 125 engine at 50 Hp, raising the head exit temp from 50 to 60* looses a couple of Hp instantly.
The deto sensors are connected one wire to earth, the other to the guage.
A good direct connection to the guage and chassis earth is essential.
In the units I have tested with two wires I havnt seen any connection of the sensor body to either of the wires and polarity doesnt seem to matter - except where there is a shield
strap.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
Thanks for confirming that, I was concerned because I had to guess, but it turns out I connected it properly.
The earth in my arrangement connects everything in a star arrangement, Battery, Ignitec, Deto Filter, Deto Pickup, Frame, Ignition Coil and Engine.
There are direct paths between complimentry pairs like Ignitec and LT side of the coil and engine and HT side of the coil and everything is tied to ground without the ground return for the LV side having to share a direct path with any HV stuff.
With my wiring layout everything is connected by copper wire to earth (or 0V at the center of the star), and the frame is just one element directly tied to earth.
The frame itself is not intended to be an earth path for anything as there is a piece of 0V copper wire for everything thats doing the earthing job. This star arrangement should cut down on signal noise.
Hi TZ, ran the ATAC this weekend - hard to know how much difference it makes but does seem to work![]()
First one is good.
The second one is shinnier and has clearer pics (but he has no idea LOL)
Keen observers will notice the offset butterfly so as to minimise flow disruption. Plus it is orientated to further minimise the disruption to flow.(Blade direction)
As has been previously pointed out.
Back to the shed? For mk2 I must admit i missed that little gem myself as well
What is yours made from a carb butterfly?
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Kinky is using a feather. Perverted is using the whole chicken
Look at the 2nd page here: http://www.bosch.com.au/content/lang...sors_knock.pdf
The two-wire sensors have their pins mentioned as "signal" - both of them. So I guess it just does a "|Vsignal1-Vsignal2|" and it's independant of polarity, as Wob already said.
The third wire of some sensors is mentioned as "shield".
No, unfortunately I haven't tried mine. I am saving some € to buy the gauge.
Here's some installation instructions:
Installation instructions
The sensor’s metal surfaces must make
direct contact. No washers of any type are
to be used when fastening the sensors.
The mounting-hole contact surface should
be of high quality to ensure low-resonance
sensor coupling at the measuring point.
The sensor cable is to be laid such that
there is no possibility of sympathetic
oscillations being generated. The sensor
must not come into contact with liquids for
longer periods.
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