ESE's works engine tuner

**richban** · 8th February 2011, 12:47

Originally Posted by wobbly

Dont be a big girls blouse - the FXR with 48.8 stroke should be at 13000 all day, its well under 4500 ft/min and the pressure fed big ends are way less prone to cage skidding causing failure..
Christ the 450 singles are reliable to 12500, after that it gets horrible real fast.

OK 13 sounds good. Now if you could just join forces with Kev again and design an exhaust cam head package to see off some of them 2 strokes you have been building.

**wobbly** · 8th February 2011, 13:45

Get Kev to fill in the inputs needed for my header design program I gave him a while ago, easy to make a screamer if the FXR hardware is able to be "fixed" properly.

**richban** · 8th February 2011, 15:26

Originally Posted by wobbly

Get Kev to fill in the inputs needed for my header design program I gave him a while ago, easy to make a screamer if the FXR hardware is able to be "fixed" properly.

Sweet will do.

**kel** · 8th February 2011, 16:23

Attachment 231390

Originally Posted by wobbly

Get Kev to fill in the inputs needed for my header design program I gave him a while ago, easy to make a screamer if the FXR hardware is able to be "fixed" properly.

There's something wrong with your attachment, I can't enter any data into the fields

**richban** · 8th February 2011, 17:30

Apart from looking cool and probably costing a lot I would like to see if these things work. The bit on the bell not the carb. I might try making one.

**TZ350** · 8th February 2011, 19:28

.

Attachment 231402

Faw...rk ...........a 25hp 4-stroker with a long liner power spread, now what am I going to do?????

**Henk** · 8th February 2011, 19:41

Originally Posted by TZ350

.

Attachment 231402

Faw...rk ...........a 25hp 4-stroker with a long liner power spread, now what am I going to do?????

Buy an FXR?

**kel** · 8th February 2011, 19:51

Originally Posted by richban

Apart from looking cool and probably costing a lot I would like to see if these things work. The bit on the bell not the carb. I might try making one.

Thats so hot, hate to think what it costs.
I have a couple to try this weekend admitable not yoshi quality but nice 25 and 50mm bells/stacks what ever you want to call them. Also have some to sell if anyones interested.

[ATTACH]Attachment 231405[/ATTACH]

**richban** · 8th February 2011, 21:31

Originally Posted by kel

Thats so hot, hate to think what it costs.
I have a couple to try this weekend admitable not yoshi quality but nice 25 and 50mm bells/stacks what ever you want to call them. Also have some to sell if anyones interested.

[ATTACH]Attachment 231405[/ATTACH]

I did some testing with some that look the same last year at manfield. I was surprised how noticeable the lenght change was. Ended up sticking with the short one. Was easy on the big open straights on full noise.

**wobbly** · 9th February 2011, 08:27

You have to print the attachment and fill it in, scan and send to me.

**TZ350** · 9th February 2011, 14:29

Originally Posted by richban

Apart from looking cool and probably costing a lot I would like to see if these things work. The bit on the bell not the carb. I might try making one.

Attachment 231453

I am not sure how this is supposed to work, a venturi ejector maybe. But if there is a tuned length aspect to it then one could have two or more different lengths that swing into place and a controller like the IgnTech could position the different lengths in front of the bellmouth according to the rpm.

**koba** · 9th February 2011, 14:33

Originally Posted by TZ350

Attachment 231453

I am not sure how this is supposed to work, but if there is a tuned length aspect to it then one could have two or more different lengths that swing into place and a controller like the IgnTech could position the different lengths in front of the bellmouth according to the rpm.

Or maybe in the case of the pic the different behavior of the air at different revs takes care of the transition.

I know that doesn't really make sense but its the best way I can put what I'm thinking.

**kel** · 9th February 2011, 14:51

Some more RSA125 development info from Jan Thiel

"No pressure transducers were ever used in our engine development.
And time/aerea was never calculated.
The port timings remained practically the same during 15 years!
What we did was trying different angles and radiuses, mainly on
the transfer ducts. I think we tried 40 different types of transfer ducts
that did not chanche the time/aerea. It was all about in which direction
the charge entered the cilinder and how the tranfer streams influenced upon
each other! Also about 200 different exhaust pipes were tried. After 2004
nothing much was changed but we improved with different power jet and
ignition mapping. It seemed nearly impossible to improve the transfer ducts
any more. The exhaust ducts were CNC machined, using different programs,
mainly to reduce exhaust duct volume. Also about 100 head designs were tried"

Didnt calculate time area? Im guessing that means the time area requirement hasnt changed any in the last 15+ years.
So there you go its all about the transfer ducts, now where have I heard that before?
Check out the attached photos, I guess the idea of thinning the transfer duct bridge has gone out the window, and the exhaust duct hows that for a crazy shape

Attachment 231454
Attachment 231455
Attachment 231456

**koba** · 9th February 2011, 15:02

Originally Posted by kel

Some more RSA125 development info from Jan Thiel

"No pressure transducers were ever used in our engine development.
And time/aerea was never calculated.
The port timings remained practically the same during 15 years!
What we did was trying different angles and radiuses, mainly on
the transfer ducts. I think we tried 40 different types of transfer ducts
that did not chanche the time/aerea. It was all about in which direction
the charge entered the cilinder and how the tranfer streams influenced upon
each other! Also about 200 different exhaust pipes were tried. After 2004
nothing much was changed but we improved with different power jet and
ignition mapping. It seemed nearly impossible to improve the transfer ducts
any more. The exhaust ducts were CNC machined, using different programs,
mainly to reduce exhaust duct volume. Also about 100 head designs were tried"

Didnt calculate time area? Im guessing that means the time area requirement hasnt changed any in the last 15+ years.
So there you go its all about the transfer ducts, now where have I heard that before?
Check out the attached photos, I guess the idea of thinning the transfer duct bridge has gone out the window, and the exhaust duct hows that for a crazy shape

Attachment 231454
Attachment 231455
Attachment 231456

Very Interesting Pics!

**TZ350** · 9th February 2011, 16:50

Ok this is where I am at now........

Attachment 231462

Ran the tripple Ex port up. Blue Line. Red line is my old single Ex port.

Attachment 231461

Clutch slip at about 12.5 and timing and carburation all wrong.

I am looking forward to seeing what it looks like when everything is setup and dialed in properly.