Author Topic: TZR125 4DL TRACK BIKE  (Read 85913 times)

Louis

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Re: TZR125 4DL TRACK BIKE
« Reply #240 on: February 27, 2018, 06:58:45 PM »
Martin,
Quote
I wonder what the transfers are like? because it's easy enough to widen the exhaust port. It's still a lot of money for a non original though! And I wonder how good the plating is.. Could be a good cylinder to practice on perhaps Louis

I wasn't that enthusiast when I saw the cylinder in the first place, but will make a portmap for indication purpose :)
For the moment I have to many project, Making a TZR125 engine with 3MA cylinder, upgrade my dyno, and working out my dry clutch project.

You need to do a lot on that cylinder, the ypvs drum from a 3MB wont fit the imitation cylinder so you need to change it to
But who knows, perhaps in the future will give it a try ^-^
King off all twostrokes ''TZR250 3MA''

Louis

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Re: TZR125 4DL TRACK BIKE
« Reply #241 on: February 27, 2018, 07:08:52 PM »
Hello 2stroke

Yes what you mentioned is well known, you forgot the gear ratio difference ;)
My special engine will be more close to a SP engine, but that one is still far away from ready. (Building one with a 3MA cylinder and 3MA SP head)

I have tried to joined the 125 forum from in Italy :), but because I can't read Italian so failed to join ::)  (as I can't log in)
https://125stradali.com/

Had hoped to find more info from the Belgarda and SP version as the bike is build in your country.
I belief bin reading that there where special cup cylinders for the SP class????

King off all twostrokes ''TZR250 3MA''

2stroke

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Re: TZR125 4DL TRACK BIKE
« Reply #242 on: February 28, 2018, 02:08:18 PM »
Louis, nice to know that you are an expert on 4DL SPs. Your experience may be useful for many enthusiasts. ;)  I know many people in the forum you mentioned. I've designed and realized special parts for some of them and also racing parts for the current "SP" championship. Sadly, there isn't any "running" TZR: the challenge, today as in the 90's, is between Aprilia RS and Cagiva Mito. Anyway, you've  choosen a good place to find info about our bikes, and above all, amazing & professional friends. (-P)

I've been living the SP "era", directly, I've friends that raced in the original 90's SP championships. TZR "SP" was made to compete in those championships.
I resumed only the main differences between a normal TZR R and a TZR SP, to make people remember how to recognize a real SP. I said "only main differences", because there is a myriad of very small differences, that could only be perceived "live", at that time. Impossible to read on a website. On the other hand, it's very difficult, mixing the parts, to closely revive the real "SP" performances. For example, among many other tunings (as my special inlet manifold ), I use the "SP" ignition/PV map, and a 0,65 squish on my track bike, but the very good performances, are not even close to the SP one's.

I didn't mention gear ratios, because, in the only 95 pieces of Belgarda Sps sold here in Italy, you could barely find two identical bikes : since it has been an "handcrafted special", every bike is one of a kind. For example, some used standard gear ratios from 3MB engine version, other ( as you notice) had the SP version's. The gear ratios may be changed depending on the track and on the championship rules (and its year). This is valid for may parts, for example, the exhaust. 8)

TZR 125 R SP was rare and there isn't many people who really knows or remember all the peculiarities of this model. It's a sort of "legend" ;)

As far as I know, there were some special cylinders developed for the SP that really ran on track. That was quite common, as it happened for other brands.

If you need more info, for the ones I remember, please feel free to ask. ;)
« Last Edit: February 28, 2018, 08:32:34 PM by 2stroke »

Toop

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Re: TZR125 4DL TRACK BIKE
« Reply #243 on: February 28, 2018, 04:11:06 PM »
Like this one ?

Chris_

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Re: TZR125 4DL TRACK BIKE
« Reply #244 on: February 28, 2018, 06:13:54 PM »

2stroke: "Your experience may be useful for many enthusiasts."

Yes, indeed !!! I´am a 2Stroke-Beginner and i have learned so much from Louis ! I like that he shares his experiences with other folks/guys. He has helped me a couple of time. Thumbs up

Regards

Chris
« Last Edit: March 24, 2020, 05:02:00 PM by Chris_ »
Yamaha TZR 125 DL RR Belgarda
Sachs ZZ 125
Yamaha TT 600 R Belgarda Supermoto
Yamaha TDR 250

2stroke

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Re: TZR125 4DL TRACK BIKE
« Reply #245 on: February 28, 2018, 08:21:58 PM »
Hello Chris and Toop, are those your cylinders or did you take the pictures from the web?

The shots are not in the best angle possible to see details about important parts of the cylinders. However, basing on the current pictures, one of them looks like the original (or is a very accurate clone)...require more elements to give a more precise response. For example, it's important also to see the head and how some codes are impressed on the metal of the parts. ;)

Chris, I agree with you when you say that Louis is doing an excellent job here. His "experiments", supported by knowledge and instruments and the scientific approach are a good tool to measure progresses.  (-P) (-P)  This is a positive attitude into a forum: to share knowledge so that other users can share the enthusiasm and test their own progresses and ideas.

 :) Everyone of us can learn from the comparison with others...having a respectful & proactive approach. ;)

I'm in the "two stroke enthusiast" since the 90s...if my expertise can help you..I'll be glad to share details and materials :)  As far I remember, on last June, Louis himself shared one of my TDR's dyno run on the DT125R forum, to support his ideas. :D


So, people of this forum, feel free to ask! ;)




« Last Edit: February 28, 2018, 08:55:22 PM by 2stroke »

Louis

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Re: TZR125 4DL TRACK BIKE
« Reply #246 on: February 28, 2018, 10:02:14 PM »
Hello 2stroke,

Im far from a ''expert'' that's for sure  :o I'm just a hobby guy who is experimenting with different setups that's all.
I'm relative new to the 125's (still learning)

Now you mentioned I did post a TDR curve witch had a 30HP, now I know the man behind it.
When I read that topic again, I know it is you as you have the same specific line there as you have here

''please feel free to ask''

I'm not afraid off asking :)
I like to know if there are dyno runs known from a real SP (or SP track bike)
As they are mentioned to have a 30/31 HP are those Rear wheel HP's or crank HP's?



« Last Edit: February 28, 2018, 10:06:40 PM by Louis »
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Louis

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Re: TZR125 4DL TRACK BIKE
« Reply #247 on: February 28, 2018, 10:07:20 PM »
Hello Toop,

Marked 325 in frond off GILARDONI is a new one to me.

That looks like a SP CUP cylinder (or perhaps KIT cylinder)

Is it yours?
« Last Edit: February 28, 2018, 10:09:45 PM by Louis »
King off all twostrokes ''TZR250 3MA''

Toop

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Re: TZR125 4DL TRACK BIKE
« Reply #248 on: February 28, 2018, 10:30:11 PM »
I did not buy it because it misses the valve and the piston. I watched it go a few years ago  ;)


« Last Edit: February 28, 2018, 11:07:11 PM by Toop »

2stroke

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Re: TZR125 4DL TRACK BIKE
« Reply #249 on: March 01, 2018, 10:45:00 AM »
Since we are talking about this dyno-run's graph, I think it's a good idea to show it to other forum users :) :



The most important thing is not the peak power increase , but the fact that with my special parts tuning...there is about 3.7HP gain in comparison to the original setting, without loosing power/elasticty at low-mid range. One of the main reasons is that I used a 28mm (fine tuned) carburetor as it happened in the original SP racing championship.

As usual, feel free to ask if you want to know something about my track-bike setup. :D

I will take a look at the materials I have in my archive and see if there is still something about the TZR 125 R SP. As far I remember, some dyno-runs from the 90s talk about from 31Hp to 33Hp at rear wheel, depending on the special handcrafted setup they've received in the factory. The important is not peak power, but how power is distributed on the powerband : it helps to come off the circuit curves, faster. 8)


« Last Edit: March 01, 2018, 10:46:45 AM by 2stroke »

Martin77

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Re: TZR125 4DL TRACK BIKE
« Reply #250 on: March 01, 2018, 01:04:35 PM »
That's about the same as I got from a 4FL engine. Dynojet readings are about 10% higher than other dynos, so it's also probably a good match for Louis results too. But it's still a neat result..

What was the specification for your engine 2stroke?

2stroke

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Re: TZR125 4DL TRACK BIKE
« Reply #251 on: March 01, 2018, 02:07:01 PM »
Dynos often show rather variable data (5-20%) : if you look at the test conditions, you may note that the second test has taken a slight advantage by the ambiental conditions : lower temp, lower humidity and higher barometric pressure. Factors that are quite important on a 2 stroke bike performance.  :-\ For both tests, gasoline was the common 98 octane. Correction factor is EEC, that is well known to be not so friendly with "hp" as the SAE or STD, that are older than this. :shock:

TDRs Belgarda were omologated between 27Hp and 28Hp at crankshaft, and if you consider an average loss (for a 125cc - 2 strokes bike) of 1.2/1.5 hp from crankshaft to wheel, you are aligned with the dyno "stock" engine reading.
Dyno-runs from the 90s showed, for my model, powers from 25,5Hp to 27Hp at wheel.

I'm not interested in showing "big numbers", but to share with you the fun that I have in designing, realizing my "special parts", and finally testing them exclusively on circuit. My favourite part of the graph is when the two curves cross themselves at the "stock" curve power peak : this means that I've gained without any "side effect" about 950RPM of pure power after 9500RPM. 8)

The tuning I performed on my bike is "personal", in the sense I have studied, designed and optimized every detail. To be clear, the admission manifold is at its 4th generation along 8 months of study and tests. I have two programmable CDIs (I developed many ignition/PV maps), dedicated carburetion and so many other details, difficult to reassume, without writing a "book". ;D

Anyway, the main are:

1)Cylinder/head/piston : Squish value reduced to 0,65. Optimized/redefined ports and transfers. Copper head gasket. Two rings very light piston (implies rebalancing shaft /countershaft) . Smoothed YPVS design.

2) Optimized inlet manifold, without "boost bottle". Refined reed valve.

3) Optimized original 28mm PHBH Carburetor, dedicated carburetion.
4) Handcrafted air filter, airbox inlet redesigned.
5) Original expansion, but longer silencer.
6) Reinforced clutch and related springs.

 ;) A passionate advice : cure precisely the assembly tolerances of parts and and the set up. ;)

Chris_

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Re: TZR125 4DL TRACK BIKE
« Reply #252 on: March 01, 2018, 06:23:51 PM »
:“So, people of this forum, feel free to ask”

I really appreciate it  (-P). I am very impressed how much help the members offers to each other here at the forum ! That is not ordinary. At my homeplace the guys create a big secret of their experiences ....anyway.

As a very interested 2T-Newbie I have so much questions that I want to discuss or to be answered. I think I have to open an own new thread…maybe called “Basic-Questions TZR”. I don’t want to disturb this threat with my questions ! 

I would like to spend some experience here for the forum/guys,  but the problem is,  I have no experiences to share :-[ 

Now….back to topic

Greetz

Chris
« Last Edit: March 24, 2020, 05:08:58 PM by Chris_ »
Yamaha TZR 125 DL RR Belgarda
Sachs ZZ 125
Yamaha TT 600 R Belgarda Supermoto
Yamaha TDR 250

2stroke

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Re: TZR125 4DL TRACK BIKE
« Reply #253 on: March 02, 2018, 12:59:27 PM »
Chris..you are welcome! :)

Let's go back to the topic, now : I'm eagerly curious to see the new depelopments of Luis's track bike based on the latest cylinder transfer/port tuning. (-P)

Louis

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Re: TZR125 4DL TRACK BIKE
« Reply #254 on: March 03, 2018, 11:10:28 AM »
Well it have to wait one more weekend :-[

I need to visit a hospital for two days, turns out that something in my body is not working correct.
Hope its not something critical, and could be fixed with a medicine
We will see....

I'm also curious what a +/-2mm lifting off the transferports do

Will let you guys know
King off all twostrokes ''TZR250 3MA''