DT125R FORUM

Sometimes thinks do not go as planed.
When you belief in something that hard, and your are convinced that others have it wrong it will take you some time to conceder that they are right.

It turns out that my own dyno was not set correct, re calculated my drum an that gave a massive drop in the measurements.
Of course not very nice for me to know, as I thought I was going the right way.
Thankfully don't have a company/ or a tuners name to keep high so a note on my site regarding the wrong setting should be enough.
http://www.tzr3ma.com/dyno-correction.html

But specially here I post a personal reaction, because they told me here over and over it is not making a +30HP and I did not belief it.

So my apologies for that.

The trough now is as followed.
After the new settings the HP's where dropping faster than I could think off.
But fair is fair, if this is what it should be, so be it.

The results so far

Stock the TZR125 (trackbike) has a 22,3HP at the rear wheel
And with all the mod's i did so far (shortened exhaust, 6 degree more advance, changed carb rubber, open carb) it produced 24,8HP rear wheel.

Currently have changed the head to a O-ring conversion, but need to dyno it first.
http://www.tzr3ma.com/head-to-o-ring-conversion.html
It drops the squish from a 1,3 to a 1mm and combustion volume to a 11,2cc

Hope this will bring me a 1,5 a 2 HP and it end up around 27HP
(not saying it will, but hope it does)

After this like to do some other steps but that would probably bring more in the mid section than on peek power

Will let you guys know

Cheers
Louis

Well what about this. I'm the first topic starter here.

As I mentioned I'm building a TZR125 Track bike

http://www.tzr3ma.com/tzr125-track-bike.html

Now i'm investigating the Tuning aspect for my project
I like to see what is possible with combining stock components to gain max performance from a stock engine.

What I mean by leafing it stock is no porting, no head changing, no programmable ignition.

My setup for the moment is this.
-Stock engine (Real condition unknown, by the look of the engine/piston relative low mileage) http://www.tzr3ma.com/engine-2.html
-Shortened exhaust by 10mm
http://www.tzr3ma.com/shortened-exhaust-en-tacho-change.html
-Pickupmove of 4 till 5 degrees
http://www.tzr3ma.com/tzr125-stock-performance.html
-Changed carb rubber
http://www.tzr3ma.com/changed-carb-rubber.html
-Stock CDI
http://www.tzr3ma.com/tzr125-4dl-cdi.html
-Stock YPVS

Now like to know if there are people who have experimented with different servo motors. (openings curve is set in the servo it self)
The 3MB servo is opening a bid to quick for a higher rev engine.

But what does a servo do from a?

• TZR 4FL
• GPR 125
• Sachs XTC
• etc

Anybody experimented/measured these?

Cheers

''think we will have to agree to disagree about the engine output of the Belgarda 4DL engine''
No problem, remember I don't mean you any harm just have a different point a few.

''I was under the impression that the 4DL engine was going to be a monster. But it was poor''
No its not a monster at all that is for sure, your yz125 will kick its ass any time.

''I have examined both engines in great detail, there. Is nothing to suggest that the 4DL engine was 10 horsepower more than the DTX engine''
That I belief, apart from a slightly different timing from cylinder perhaps a tiny difference in head design.
Think the main difference is electronically, carb and exhaust compared with the 3MB engine
(Are there no restrictions in the exhaust on a DT125R (just a thought))

Have quickly draw a 4DL curve inside a DT125R curve.

As you can see after the 9300rpm the 4DL curve is different. (its designed to peek higher)
This is a big difference at about 10.300rpm the 4DL has 10degrees and the DT125R has 4degrees

That is a 6 degrees differences

For example if you see how much the 4 degrees pickup move does on the TZR it gained about 2,5HP
http://www.tzr3ma.com/tzr125-dyno-runs-two.html

So calculating it back lets say 26HP -6 degrees (roughly 3HP) will be 23HP this in combination with a stock exhaust (witch will peek less then a TZR one)
You end up with around 22HP??

Know its all guessing, its just a other point a few

Some pictures regarding this project

For testing some off my ideas I can use my street 4DL

For CDI ypvs testing I'm working on adapting my (testing machine)
So I can measure/test the 4DL CDI and YPVS motor

The project it self

Most can be seen on my site.

Slowly getting the feeling that nobody have measured the 4FL servo motor or any other one??

Cheers

The piston looks like you went to lean.
Google "lean piston" and you see many like them.