ESE's works engine tuner

[bucketracer]

Kent andersons bikes were a completely different animal and I don't have any info on what power they produced but i would guess at mid 30's. Say 34-ish

If thats 34-ish crank hp then TeeZee's 31 rwhp puts him about 33-34ish too.

And comparing TeeZees efforts with the factory racers of the sixties is not exactly apples for apples but I thought it would be interesting to check it out.

His bike compares well to the Suzuki 125 air cooleds but the 42 hp 12 speeds leave him behind untill you realise how peaky they must have been.

It looks like the golden time was for 2-3 years in the later part of the 60’s

Suzuki 125cc Racers of the 60's

1960 RT60 13ps @ 11,000 rpm air cooled

Degner is working with Suzuki about this time.

1961 RT61 15ps @ 10,000 rpm air cooled

1962 RT62 20ps @ 10,500 rpm air cooled

1963 RT63 25.5ps @ 12,000 rpm air cooled

Hugh Anderson is riding for Suzuki

1967 RT67 42ps @ 16,500 rpm water cooled and 12 speed gear box.

1968 RT68 42ps @ 16,500 rpm water cooled and 12 speed gear box.

At about this point the FIM killed of the multi cylinder tiddlers and limited the 125's to 2 cylinders and six speeds.

My source:-

http://www.suzukicycles.org/history/...960-1967.shtml

[twotempi]

The Suzuki 125's that you refer to are probably the 1977 air-cooled TR100 ( XR21) , TR125 ( XR24 ), plus the watercooled disk-valve 1978 RJ100 ( XR29 ) bikes.

These are documented in the Appendices of the book "Team Suzuki" by Ray Battersby. Claimed power output is 28.6 HP @ 11250 for the TR125 and 25 HP @ 11500 for the RJ100.

So TZ350's GP125 is still king !!

[bucketracer]

These are documented in the Appendices of the book "Team Suzuki" by Ray Battersby. Claimed power output is 28.6 HP @ 11250 for the TR125 and 25 HP @ 11500 for the RJ100.

Is that crank or rear wheel? hp .....

[F5 Dave]

The Suzuki 125's that you refer to are probably the 1977 air-cooled TR100 ( XR21) , TR125 ( XR24 ), plus the watercooled disk-valve 1978 RJ100 ( XR29 ) bikes.

These are documented in the Appendices of the book "Team Suzuki" by Ray Battersby. Claimed power output is 28.6 HP @ 11250 for the TR125 and 25 HP @ 11500 for the RJ100.

So TZ350's GP125 is still king !!

if you don't say so yourself.


3 posts, female, rare as hens teeth in NZ bike listed. What happened to Fred with the Manx?


Hi Rob.


[edit] ok appears I'm wrong. this never happens to Scooby Doo.

[bucketracer]

if you don't say so yourself. Hi Rob.

.... No not TeeZee, hopefully see some pictures of interesting 70-80's 125 and 250 Italian race bikes/engines soon.

[twotempi]

To F5 Dave,

thanks for advising me of my sex change !!

Have changed my profile to reflect what I noticed in the shower this morning !!

[husaberg]

The customer TA125 was approx 24 hp claimed and this seems abouit right with a top speed of about 110-115 mph. Power was/is between 9500 min to 13000 max. Very little below 9500.
Kent andersons bikes were a completely different animal and I don't have any info on what power they produced but i would guess at mid 30's. Say 34-ish

Another guy in America ( relocated Frenchman ) created a very sucessful 125 based on a 125 AS3 engine called a GBS ?? which equalled or exceeded the Andersons bikes. The acronym was " Garage Bin Special" or similar.

The TA125 gearbox had 5th gear a bit tall for the engine to bridge the gap. A slightly lower 5th gear from the RD125 will fit and allows the engine to still accelerate when changed from 4th to 5th.

Although a nice little bike it comes standard with a hinge in the middle of the frame, and a rear swing arm on rubber bushes allowing movement in all 3 axes directions rather than just up and down !!

the article on air-cooled cylinders was very interesting, is there any info available on side-by-side twin cylinder engines where the airflow between the cylinders is restricted. Some intelligent ducting must help in this instance.

Kent Anderson was 125 world champion two years running on a modified importer suported TA125 modified yes but what proddy clubmans bike wasn't.
i doubt the Yank/Frenchman can match that.

[twotempi]

There has been a bit of historical confusion about the Yamaha 125 twin that won the World Championships

Kent Andersons bike was

1) Watercooled - TA 125 was aircooled

2) 44 bore x 41 stroke - TA125 was 43 x 43

3) Different frame - TA125 frame is considerably taller - ( Hard to believe that it could be smaller but............. )

4) 32mm forks - TA125 has 28mm

5) Was not a TA125 modified by Yamaha Amsterdam - It was a altogether totally different machine


I would commend you to also look at Ferry Brouwers Classic Yamaha website which gives the specs and images of this bike which he owns and demonstrates.

Will try to find the website with the French bike details for - The guys name is Thierry Espinay and the bike was raced very successfully in the States and is a work of art.

Fritz should know this gentleman.

[husaberg]

There has been a bit of historical confusion about the Yamaha 125 twin that won the World Championships

Kent Andersons bike was
1) Watercooled - TA 125 was aircooled
2) 44 bore x 41 stroke - TA125 was 43 x 43
3) Different frame - TA125 frame is considerably taller - ( Hard to believe that it could be smaller but............. )
4) 32mm forks - TA125 has 28mm
5) Was not a TA125 modified by Yamaha Amsterdam - It was a altogether totally different machine
I would commend you to also look at Ferry Brouwers Classic Yamaha website which gives the specs and images of this bike which he owns and demonstrates.

Will try to find the website with the French bike details for - The guys name is Thierry Espinay and the bike was raced very successfully in the States and is a work of art.

Fritz should know this gentleman.

Oh i do love an historical debate not really the place but Ferry's site you quote lists the bike as having a A wait for it..........
AS3 IE (TA125) based engine.
modified with water cooling and other mods. The real question is when does a bike cease to be the bike it started as.
I don't know or really care to guess but.......
The Brakes and forks i see as a non issue. Why have a look at the mid 90's gp glass most of the forks brakes were changed on the Hondas even the crankcases on a lot of them the cylinders were pretty much all kit ones A or B if you were lucky/Talented/or Rich.They were still a Honda rs125 though.
There no denying the kent and chas bikes received "unofficial works support" but they were production based. Hense the kickstart shaft. Why else would they have that? Not a lot of Works specials should have those? Although Yamaha did leave the autolube on a lot of bike though.
Pm me because, i don't think we should clutter up the thread with, what is on the whole, unimportant stuff.

Yamaha 623C (kent)
Although Yamaha had officially retired as Factory Team, developed of racers based on production motorcycles continued. For 1969 the YZ623 was planned, a racer based on the AS1 roadbike. 5 pcs were made for Europe. Jean Auréal won the French GP that year on one of the YZ623 machines beating Dave Simmonds on the factory 125cc Kawasaki. Lothar John from Germany saw the potential of the 125 engine and built his own 125 Yamaha racer, with some good GP finishes. To be followed by many privateers who used the 125 Yamaha engine. (Ludy Beumer pays a lot of attention to the various 125 Yamaha racers used on his website www.classicyams.nl

For the 1971 season Yamaha had developed a real racer from the YZ623, the frame was drastically changed, front and rear suspension and brakes of the RA31A 125cc 4 cylinder, lightweight frame parts, the AS3 configuration engine, CDI ignition, were all used. Riders selected to ride the bikes were Yamaha Motor NV supported rider Kent Andersson and Rod Gould. After a sighting lap Kent decided that he did not want to race at the Isle of Man, at the spot Chas Mortimer was recruited by the Irish Yamaha Importer Mr Danfay and proposed to Mr.Minoru Tanaka the responsible Japanese person from Yamaha Motor NV . Winning the TT secured Chas a machine for the rest of the season to ride, also because Rod did not like the 125 at all. Chas finished 5th in the Worldchampionship.
For 1972 the machines were updated to water-cooling, dry clutches and increased horsepower. Riders Kent Andersson, Chas Mortimer. Chas finishing the season with most gross points (121), and equaling Kent (gross 103) on nett points 87 finishing 3rd . Should he have been the Worldchampion?
For 1973 Kent got a new machine, with improved power. Main difference was larger transfer ports. The same applied again for 1974, when new team mate Bruno Kneubühler also got a new OW15. Both riders replaced the drum frontbrake by twin “scarab” disc brakes. They finished 1st and 2nd in the Wolrdchampionship. For 1975 Yamaha supplied new improved engine parts and tuning information, but the machine were the 1974 machines.
The YCRT machines are the genuine 1972 YZ623C machines, the OW15 is a replica.

http://www.yamaha-classic-racingteam.nl/site2/index.php?page=125cc_623c2
http://www.yamaha-classic-racingteam...5cc_623c2_tech

Turns out TZ is in the hunt for HP with the works bikes though admittedly piston ported and liquid cooled twin cylinder ones from 1970's.

[twotempi]

Fair call Husaberg.

Would be good to catch up one day.

Have a look a this website for the details of the "GCS" special at the bottom of the website page.

This guy was in the fine tradition of "bucket" style bikes, and deserves an honorable mention.

http://www.tsrfcars.com/toys-full_size_morbidelli.htm

Some good ideas as well


cheers

[TZ350]

Interesting about the Factory air cooled race bikes from the 60's and 70's. I didn't know I was doing so well .....



Suzuki RS67 1967
February 1967 - August 1967
Engine type: Water-cooled 125 cc square-four 2-stroke.
Bore x Stroke: 35.5 x 31.5 mm
Compression ratio: 8.4
Carburetor: VM24
42 hp / 16,500 rpm (350 bhp per liter), 145 mph.
Transmission: 12 speeds

But the real hero in all of this is Speedpro with his Wobly designed 30 rwhp MB100, with water cooled head as its making near 350 crank hp per liter, so there truly is a Bucket that foots it performance wise with the big factory boys from the golden era of GP racing.

Speedpro has built a Bucket that pretty much makes the same power per liter as the RS67, now thats a real achevement.

[husaberg]

Well seeing as we are not all ridding SPX engined bikes i guess it didn't set the world on fire.
But then again it did take Norton a while with the Norton rotary so who knows.

But there are some interesting bits with the design as well. ESP as to why the uninspired can find the music produced by a 2 stoke on the pipe as iritating.
As well as these designers solution as to a way around the problem. Hooper was a clever guy.
There was a bit in the article i was planing to keep to myself, but it it is well shrouded i doubt most people would pick up on it.
It is in fact a real clever tuning aid. I will just keep plugging away on it myself if no one else does.
I have also seen other articles which discuss the actual engine in more detail. but not the whys.
Oh by the way i posted in in a random order after i fixed my inadvertant mirror image posting of one page now it will not post the attachments in the correct order
Why is that?

[Frits Overmars]

O yes, the Wulf. The stepped pistons require that the cylinder bores are perfectly in line. But the sideways-poking exhaust ducts cause a very uneven heat distribution so those bores are anything but round during operation. What can you do about that? Use air cooling......

Here is a little principle sketch; it may be easier to understand than the pictures with the many streamlines in the publication above.

[husaberg]

O yes, the Norton Wulf. The stepped pistons require that the cylinder bores are perfectly in line. But the sideways-poking exhaust ducts cause a very uneven heat distribution so those bores are anything but round during operation. What can you do about that? Use air cooling......

Here is a little principle sketch; it may be easier to understand than the pictures with the many stream lines in the publication above.

Always pushing that new fangled water cooling Frits
It was the prototype the production engine was to be water cooled.
Was it a lot cleaner re emissions.It looks like it should have been. i also see the transfers could be modified by increasing the thickness of the plates, and it was to be fuel injected.Dribble feed though.
Zero balance factor interesting lubrication system. 4 stroke annular discharge mufflers. Al Alloy rods plain big ends.
Is there merit in the engine design or just for a slugger commuter?
Shame the Brits never did seem to invest much in R&D.


Thanks for the diagram.

[TZ350]

Pictures of an OW15 sent to me by twotempi



And the GCS

Have a look a this website for the details of the "GCS" special at the bottom of the website page.

This guy was in the fine tradition of "bucket" style bikes, and deserves an honorable mention.

http://www.tsrfcars.com/toys-full_size_morbidelli.htm

Some good ideas as well