ESE's works engine tuner

[TZ350]

The TZ500 pipe graph was the last run of the night and it never went back on the dyno so we are positive we can tune the 'peak' part of the curve to something better.
I don't recall any port timing numbers but when I built it I used A. Graham Bells 2 Stroke Tuners Guide as a starting point and went from there. The actual number will be close to what you find in the book and I do remember it is a fairly mild number. The good thing with the disk valve motor is if you do cock it up, you can simply bolt on another disk and try again. I know people say that book is old hat but it is still relavent to a lot of buckets as they are generally old hat motors.

When modeling my engine on MOTA I would often get a peak like that and the area in front of the peak could be filled in by delaying the inlet closing point.

I know MOTA is not a real mota but it did sugest a direction to look in.

Std inlet timing was 145/55 and modified was 145/85 and as a comparison my TZ was 90/90

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[TZ350]

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So, I would say A water cooled two stroke head brings increased reliability and power. Unquestionable advantage.

I have to agree

Could someone please over complicate that for us?

and not wanting to disappoint,

I have to point out that an air cooled head is much more efficient at shedding heat than a water cooled one........yes its true!!

So why are high power race engines water cooled? now that's something to think about.....

And how is the majority of the heat transmitted from the cylinder head to the water?...... and hint, it's not by conduction

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[TZ350]

a little off what you guys are talking about could someone point me to a thread that will tell me how much better a water cooled head is and what pump to use etc (tf125) cheers

BTW in F4 you can't run water cooling on a 125 but can on a 100.

If I was running a water cooled head for extra power I would also seriously look at water cooling the crankcase's too.

I have been looking at a lot of high power kart engines and notice that some water cool the crank cases.

There are lots of places like the cavity's around the TF's front engine mounts you could run water through.

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[F5 Dave]

Don't lose any sleep, look at what he is running the TS in. Not a bike.

[Buckets4Me]

Don't lose any sleep, look at what he is running the TS in. Not a bike.

he still needs top workout how to get HP out of it before worring about watercooling the head

otherwise he may as well just buy an rs125 engine and go for both BIG HP and bling bling with the watercooled head

ps I know where there is a good rs engine for sale

[bucketracer]

ps I know where there is a good rs engine for sale

Me too, but TeeZee has fitted the carb from it onto a GP engine and I think he is looking at doing something with the ignition too.

[bucketracer]

So why are high power race engines water cooled? now that's something to think about.....

OK. I'll chance my arm here.

Its because cooling "efficiency" and "effectiveness" are not the same thing.

A British sniper is "efficient" while a patrol of gum chewing American soldiers blazing away with their automatic weapons is "effective".

It all depends on the result you want.

Internal Combustion Engine Heat Transfer Outline....http://www.engr.colostate.edu/~allan...ge1/page1.html

OK TZ if the heat in a water cooled head is not transferred from the cylinder head surface by conduction, how does it get transmitted into the water?

[TZ350]

Internal Combustion Engine Heat Transfer Outline....http://www.engr.colostate.edu/~allan...ge1/page1.html

OK TZ if the heat in a water cooled head is not transferred from the cylinder head surface by conduction, how does it get transmitted into the water?

By forced convection and micro bubbles........

Check it out here:- http://www.liquidcooledairpower.com/lc-ridofheat.shtml

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[TZ350]

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Had a few test runs up the drive on the new bike.

Much to my relief the diffuser carb idea seems to work ok,

It has 230 degrees inlet duration and still idles well.

Inlet opens 145 BTDC and closes 85 ATDC, Ex opens 83 ATDC 73% bore width and Transfers open 116 ATDC, Honda RS125 chamber.

On Taupo gearing I can even drive off from a near standstill just on the throttle and without using the clutch.

Can't tell if there is the same or any more/less power but it drives well.

Possibley get it to the dyno Wednesday to dial it in and check the shape of the torque curve.

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[sonic_v]

tz - You have so many changes compared to your present setup was wondering if your rm125 based exhaust will fit on this engine so that at least you get a back to back on the exhaust systems. Failing that if you had a 15mm spacer for the front of the rs system it would be interesting to see the results.

[TZ350]

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tz - You have so many changes compared to your present setup .

Yes its a big roll of the dice, but I have kept my RM based pipe and engine intact so I can go back to it if I have too.

Thanks to your help, the big advance on the new engine could be the much improved 24mm carburettor.

The new 24mm diffuser carb flows 50% better than the old 24mm GP125 carb as measured by our manometer and industrial vacuum cleaner test rig.

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[TZ350]

wondering if your rm125 based exhaust will fit on this engine so that at least you get a back to back on the exhaust systems. it would be interesting to see the results.

Good idea, if there is time I will try the old RM spec pipe for a comparison.

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[gav]

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My bikes engine is dragging twice the weight of F5's with maybe twice the HP, the clutch does suffer.

the crankcase's run about 100 degrees C or a little more even though I have improved the thermal barrier between them and the barrel

I have not burnt the clutch friction material right off the clutch plates yet

but the inner steels turn blue the oil smells burnt and the friction plates become cooked hard during a hectic days racing

if you think about it there are a few benifits to running with cooler oil..............

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So what gearbox oil are you running? Is Motul Transoil still the preferred choice?

[B.Crump]

Thanks guys i have jennings and gram bell tuning books i get a bit of power fade due to low speed im only doing 64km top due to the track we use so water cooling will be my next move i tryed to get a ts125 barrel but could only find a crap one does ony one know of one for sale?

[Buckets4Me]

So what gearbox oil are you running? Is Motul Transoil still the preferred choice?

auto trans fluid if I rember right the red stuff