ESE's works engine tuner

[ac3_snow]

can any one say what a 'race ready' FXR weighs in at? think I have heard about 110kgs...

[Buckets4Me]

can any one say what a 'race ready' FXR weighs in at? think I have heard about 110kgs...

sounds close enough around the 100+

[richban]

sounds close enough around the 100+

Weighed mine yesterday and it is 102 with about 2 liters of gas.

[Gigglebutton]

He He, watch out or I will tell No Mates you guys think you are fast - and he will turn up with the 5 year old 29 Hp RG100/RS125, just to put you all in the fence.

I have spoken to him already. Looks like he will come down for practice and put us into the weeds

[Gigglebutton]

I was under the impression that the reeds worked at lower revs and helped to increase the lowdown power? (I realise this also depends on the thickness off reed used)

finding an ignition is my next duty, I looked at the KX80 as you suggested tezee but they all seemed semi pricey, for this reason I grabbed a cheap RM80. Turned out to be an expensive mistake as the taper is different
So back to looking at KX80s again and if anyone wants a rm80 ignition let me know, $70ono!

I can re-cut the taper if you want

[RMS eng]

I can re-cut the taper if you want

marks TS100 has 1995 RM80 set up, taper was fine,and we ran 1980-85 RM80 and 125 rotaors on our RG50s and TS100 motors,fitted good.

[jasonu]

I would have to say the RS is the best bet, but something for those of us who find a RS physically to small for comfort.

1991 3Ln FZR250 roller $600 http://www.trademe.co.nz/Browse/List...x?id=370679045

With the original alloy wheels mine comes in at 93kg with a splash of fuel and Chambers FZR with wire wheels is 81, and I think NedKellys Honda RS was 72. (all weighed on the Mt Welly Kart track scales)

I am hopeing for 68 -70kg. My TZR weighed 76 with water and oil. We know the RS frame is 7kg less than the TZR frame. The RS swing arm is a bit heavier. This bike will have RS wheels so there will be a good saving there. If I take a good dump before getting on it that is another kg maybe more. Diet and exercise, fuck that!

[kel]

Question for Wobbly
Is there an optimum relationship between the transfer port axial angles specifically the boost. The industry standard would seem to be around 25deg main, 10deg aux and 50 to 60deg for the boost. Does the boost angle increase with the aux or is it an inverse relationship? and does a greater boost angle lift midrange power output? should the boost tangential flow taper in towards the exhaust as per the majority of recent motors Ive seen and what is the reason for this?
Ive epoxied up the boost and thought some profeesional input to the final angles might be in order.
Cheers

[rabidnz]

The mhr kits are usually pretty clearly stated as race only on most of the sites ive seen!

[wobbly]

Shit, it would need a PhD thesis to even begin to answer that question.
The problem is are we talking refining toward an optimum setup, or just trying to get shit designs to work better.
The RSA leads the way with the "refining" approach and its very evident that the inner radius size and angle is the key to keeping all the flow attached and heading in the right direction.
It has A port angles of 28 roof,16.5 floor.B port is 6.8 roof and 7.4 floor,Boost is 53.3 roof and 37 floor.
A 2008 CR250, very undersquare and with a flat top piston has 25/10/55 roof.
There is only 2 ways to optimise any system like a 2T port layout.Do what Aprilia did, employ a genius and have 150 people try shit he tells them to do.
Or, like Yamaha did around 2000 when they won the 250GP title,and use an Anemometric flow visualiser, even better a Laser Doppler one CNC driven.
We dont have those luxurys but all we can do is try to emulate what we know the trick shit stuff has for geometry,big inner rads and plenty of roof upward axial.
But if we understand why the axials are why they are that way, then maybe a light will come on above your head.
Here goes - the flat roof B ports collide in front of the boost, this clears out alot of residuals that normally are left behind, and as these opposing flows slow down - they are pulled upward by the boost port ( its flow has already attached to the rear wall).
The A port flows over the top of the B port flow, and they all join together in the rear 1/2 of the cylinder as a slowly rising column - the famous "loop".
The idea is to create as much coherent flow entering the column as possible,and at the same time clear out as much exhaust residuals as we can,ahead of that column with no mixing.
Thus if the Delivery Ratio is high, and we keep the streams entering the cylinder "coherent" then the Scavenging Efficiency will be high.Then if the pipe works properly the Trapping Efficiency will be high and lots of power is released.
If it all works together, then a 30+ Hp bucket is easy.

I dont quite understand " the boost tangential flow taper in towards the exhaust", please draw it or explain to my limited intellect in another way.

[kel]

Sorry using Yamaha's terminology and probably should have said boost tapering to the centre of the bore. See attached RGV/RS250 port map


The KE mains are at 20deg aux at 5 and boost at 55deg. I was thinking that possibly the angle relationship between aux and boost maybe inverse to help drag flow up the rear wall to the combustion chamber i.e. would the low aux angle benefit from increasing the boost from 55 to say 60deg.
I like those CR angles, they seem to agree with the majority of text Ive been able to find on the subject, but it would mean adding even more epoxy to the ports.

Another question if I may, whats the advantage of the loops to the rear of the aux transfers ports which turn the flow back towards the centre of the bore (as shown on the attached portmap), vs the angled across the boost port to the rear wall approach? Figure its to further enhance removal of exhaust gas, but (limited understanding disclaimer) wouldnt this cause seperation from the rear wall?

[wobbly]

That port map is derived from the Suzuki where the engine came from and is not very modern.
Aprilia GP has the B ports walls both dead square across the bore, with the rear wall hooks meeting at bore centre.
The boost port has parrallel side walls with taper only in the front/back direction.
Increasing the boost angle will reduce its effective flow area, and yes it will attach earlyer to the rear wall, but will be much less effective,in grabbing the B port flow and pulling it up the back.
Personally I would epoxy the A port roof, to give 25*, and fill the front wall of the B port to make it square to the bore, having a flat top septum as per the GP cylinder.

Its all a matter of trying to emulate a well we can what is SOTA and wins GPs.

[cotswold]

I just opened a flikr account so should be ok this time.

http://www.flickr.com/photos/timcoopey/?saved=1

[Henk]

Looking good. I dread to think how you will go on a fast bike.

[cotswold]

Looking good. I dread to think how you will go on a fast bike.

Be nice to find out