ESE's works engine tuner

[Frits Overmars]

So whats the go with Dutch Fisher then. Coming on here and slinging shit at Frits over historical issues that i then expand on somewhat, with facts I know are accurate as I was actually there at the time, and he goes deathly silent on the subject. Frits ignores it completely, that probably gives the posting the recognition it deserves.

Good one, was wondering what was going to happen with this. I, like many others I am sure, read his post with amazement and confusion as to what he was on about.

I was under the impression that Dutch Fisher's comment was written tongue-in-cheek, so I did not take offence. I did try to guess who he is, if maybe I know him.
Is he really a fellow countryman? I'm sure he is grinning at all this, whoever he is. Maybe he will raise the vail now?
Anyway, Wayne and Ken, thanks for standing up for me.

[kel]

, and if you dare to continue with this crap then I for one will be asking the administrators to tell you to fuck off forever

Hmm.
I for one enjoyed the amusing tounge in cheek post.

[wobbly]

I think Jans translated comments are a little off base in that yes Bartols cylinder design he was working on when at Yamaha with the 125 race team were
very Honda - ish, in that it dumped the twin boost ports ( a good thing ) but went to a T port ( not so flash ).
His cylinder was quite alot faster than the 125 teams factory versions at the time, but Yamaha management would not allow the team to use them in racing.
Bartol may have used a Honda port mould, but he had access to a Czech machine ( very probably Cees ),as did Askland, and it was the results from this work,staring them in the face, that forced Yamahas hand to finally buy one and learn
how to interpret the results.
In Y2K year the Yamaha tech director told me that they could now predict the power delivery from a cylinder purely from the scavenging pattern shown on the Czech machine
and they had quit using a dyno to tailor the powerband for the 250 project.
Also that he was very grateful that management had insisted they use the spool powervalve, as they were acutely aware of the fact they could be seen to be "copying" the Honda
and Aprilia by going square bore/stroke and wanted to retain corporate " face " by using something very Yamaha - ish, and it just happened to work a treat.
I, as are many people, admire alot of Harolds work,but the proof is in the numbers, and Jan destroyed his dyno results at Derby, and then the KTM as stunning as it was in execution, was
hamstrung by odd decisions - the pipes being a good example.

[husaberg]

I think Jans translated comments are a little off base in that yes Bartols cylinder design he was working on when at Yamaha with the 125 race team were
very Honda - ish, in that it dumped the twin boost ports ( a good thing ) but went to a T port ( not so flash ).
His cylinder was quite alot faster than the 125 teams factory versions at the time, but Yamaha management would not allow the team to use them in racing.
Bartol may have used a Honda port mould, but he had access to a Czech machine ( very probably Cees ),as did Askland, and it was the results from this work,staring them in the face, that forced Yamahas hand to finally buy one and learn
how to interpret the results.
In Y2K year the Yamaha tech director told me that they could now predict the power delivery from a cylinder purely from the scavenging pattern shown on the Czech machine
and they had quit using a dyno to tailor the powerband for the 250 project.
Also that he was very grateful that management had insisted they use the spool powervalve, as they were acutely aware of the fact they could be seen to be "copying" the Honda
and Aprilia by going square bore/stroke and wanted to retain corporate " face " by using something very Yamaha - ish, and it just happened to work a treat.
I, as are many people, admire alot of Harolds work,but the proof is in the numbers, and Jan destroyed his dyno results at Derby, and then the KTM as stunning as it was in execution, was
hamstrung by odd decisions - the pipes being a good example.

I can't comment,as only posted what i had seen and what i thought was the Fishers intent, but with regards to design often similar solutions are arrived at because they represent the best solution anyway.
I just happened to have a word document open as i was looking for a quote from either Jan or Frits regarding Balance shafts. Then i noticed the one about the Honda, Yamaha,Bartol.
None of which I thought was derogatory, just a general observation.

With regards to balance shafts I am pretty Sure Both Frits and Jan favour them.
(Forgive me if I paraphrase from memory) The balancing of a crankshaft to whatever magic factor/figure with he counterweights, does not balance the engine. It only just moves the vibration it to someewhere else in the rev range less of a nusience or something like that. (remember Paraphrase from memory)
Pretty sure the reason a lot of Balance shafts may cost power (in some situations) is more to do with oil drag brought about by a poor choice of location (RSW125 this seems to be the case my own observation likely a Rotax carry over)
Often referred to as windage (oil is 600 times denser than air)
Frits 50cc design 'the balnce shaft high mounted with sealed bearings out of the way of oil(Maybe even under a vacum )
My take is an engine construction is. if it is designed with a balance shaft, The engine design then can be made lighter (ie thinner wall thickness cases etc), also the balance shaft is also a potentially a convenient location to drive ancilleries such as water pumps. Maybe even a stator

Personally i like the older style Husaberg balancer, that is almost disk valve like in appearance, Very clever and very original.

Well first time i had seen it but it might be stream engine technology for all I know. Not that much is really new now.

I had a giggle the other day looking at a 1923 TT racebike (Works Douglas) Picture.
It had a very modern appearing front disk brake. With a caliper that was very much like a mornern cable operated Mountain bike caliper only finned.

[Muciek]

Hi guys, Does anyone seen cylinder like this? (I hope Frits know something about this one) Is this some early rotax , or "home made " one? It's fitted in 51,6 stroke engine.


Here are pictures http://imgur.com/a/Sf6Pb

[TZ350]

.

Lots of 2T cylinder sleeving and Interesting workshop projects:- http://forums.everything2stroke.com/...he-Shop/page46

[F5 Dave]

Just finishing reading Stan Stephens book, an autobiography it makes good reading. You won't pick up any tuning tips but that's not the point. There were a few bad words said about him a couple of hundred pages back here but I think they were unfounded. He's about 70 now & his success was earned from tuning production bikes within std parts restrictions. Mostly through serious hours on the dyno & fair play to that.

In your own book you do get the ability to paint things of your story without right of reply, but it does sound like he got spun up by a few of his employees effectively feathering their pockets. He's got a col in Cl Mtrcyc Mechanics mag & does some interesting projects like a large RZ500 with 350 barrels & currently a V6 RZ of some huge capacity. An entertaining writer, if probably by his own admission stuck in the 80s. But they weren't such bad years. And his CV of championships for supported riders makes for a hard stack to follow, at least at national & club level.

[2T Institute]

Hi guys, Does anyone seen cylinder like this? (I hope Frits know something about this one) Is this some early rotax , or "home made " one? It's fitted in 51,6 stroke engine.


Here are pictures http://imgur.com/a/Sf6Pb

Either home made or more likely all the rotax logos ground off .

[Frits Overmars]

Hi guys, Does anyone seen cylinder like this? (I hope Frits know something about this one) Is this some early rotax , or "home made " one? It's fitted in 51,6 stroke engine. Here are pictures http://imgur.com/a/Sf6Pb

Either home made or more likely all the rotax logos ground off .

I don't know the engine but cylinder and head are clearly Rotax-inspired like 2T-I says. The cases look like CZ or Minarelli and the carb is a czech Jikov, which would point towards Eastern Europe .

[Peter1962]

I can't comment,as only posted what i had seen and what i thought was the Fishers intent, but with regards to design often similar solutions are arrived at because they represent the best solution anyway.
I just happened to have a word document open as i was looking for a quote from either Jan or Frits regarding Balance shafts. Then i noticed the one about the Honda, Yamaha,Bartol.
None of which I thought was derogatory, just a general observation.

With regards to balance shafts I am pretty Sure Both Frits and Jan favour them.
(Forgive me if I paraphrase from memory) The balancing of a crankshaft to whatever magic factor/figure with he counterweights, does not balance the engine. It only just moves the vibration it to someewhere else in the rev range less of a nusience or something like that. (remember Paraphrase from memory)
Pretty sure the reason a lot of Balance shafts may cost power (in some situations) is more to do with oil drag brought about by a poor choice of location (RSW125 this seems to be the case my own observation likely a Rotax carry over)

Frits 50cc design 'the balnce shaft high mounted with sealed bearings out of the way of oil(Maybe even under a vacum )
My take is an engine construction is. if it is designed with a balance shaft, The engine design then can be made lighter (ie thinner wall thickness cases etc), also the balance shaft is also a potentially a convenient location to drive ancilleries such as water pumps. Maybe even a stator

Personally i like the older style Husaberg balancer, that is almost disk valve like in appearance, Very clever and very original.

Well first time i had seen it but it might be stream engine technology for all I know. Not that much is really new now.

I had a giggle the other day looking at a 1923 TT racebike (Works Douglas) Picture.
It had a very modern appearing front disk brake. With a caliper that was very much like a mornern cable operated Mountain bike caliper only finned.

Husaberg, to which design of Frits are you referring ?

I like the husaberg balancer, it is a shame that KTM dropped it when they took over husaberg.

[husaberg]

Husaberg, to which design of Frits are you referring ?

I like the husaberg balancer, it is a shame that KTM dropped it when they took over husaberg.

Not sure what he calls it ? Frits?
He mentioned it earlier here on ese but I can't find the post. It was in relation to the use of sealed bearings.
The Balancer I thought was nifty, The Water pump in the head on the earlier models not so much........
From what I understand the bearings for the balancers have to be made now, as the size is unobtainable. (must have been a Honda idea)

[Muciek]

I don't know the engine but cylinder and head are clearly Rotax-inspired like 2T-I says. The cases look like CZ or Minarelli and the carb is a czech Jikov, which would point towards Eastern Europe .

Yes, engine is CZ typ. 516 converted to rotary valve and jikov carb.

[TZ350]

Had an interesting few evenings this week playing with a small bike on the dyno. The interesting bit was watching the exhaust pipe extending 10-15mm against the retaining springs as the rpm approached peak torque and the internal pipe pressure was at its maximum. Then as the internal pipe pressure dropped the springs would pull the pipe back in for a bit of over rev.

With two springs this effect could be made to happen in two stages. I even figured out a very easy way to adjust the spring tension on the fly to tailor when and how far the pipe would slid out and back.

After peak torque the pipe would pull back in as the rpm approached peak power. I can't help thinking this trombone effect could be made to be useful in some way.

With a fixed pipe the useable power spread looked to be about 4,500 rpm with a power curve that was flat for maybe 2,000rpm. I am not sure how much the sliding pipe could be made to extend that but when I get time it sure looks worth investigating it a bit more.

[Martin1981]

No surprise that a 500ccm engine does not give more power than a 125ccm gp engine if the cylinder is mistreated like this. "The power valve ports are slightly smaller...." So why using a 500ccm engine if you don`t let it breathe? unbelievable...

[senso]

The man can know a lot and make a perfect hone with is eyes closed, but damn, its like killing cylinders, tiny ports :/