ESE's works engine tuner

[pete376403]

after thinking of the idea 20 or so years ago i found a speedway guy had done it to his engine. sounded like it did not work to good but may not of done it propery.. i dont think it would be aloud anyway been a form of supercharging

Not supercharging, but positive crankcase ventilation for pollution control. So green it should earn carbon credits!

[richban]

Sorry I haven't been following. NSR250 frame right? With the 250 engine out to 300? Looks good!

Yep NSR MC21 with 150sp Barrels. Case ported copy of Honda F3 cases and nice tidy of the stock barrels. Its fun to ride I tell yah.

[Ocean1]

I hate to argue semantics because it's hardly worth doing but a disk valve allows asymmetric inlet timing, and they both ensure that the charge is pushed through the transfers rather than out the inlet. A two stroke doesn't need a reed valve or a disk valve to operate (piston port) but allows better control of the charge. Obviously there is compression taking place here but I thought I'd point that out as an answer to your rhetorical question.

Just as a 4 stroke doesn't NEED crankcase transfer pressurisation.

Not really batting for either side, but it's interesting how convoluted the rules would have to get in order maintain some balance between the fleet if manufacturers offered anything other than 2T or 4T, there's a large number of alternatives outside the biking world that are neither one nor the other and have many of the advantages of both.

But that's what development classes should be about, exploring the chinks in the rules to some advantage, there's enough classes where it's all about the rider, fuck all where the techies get to play.

[Bert]

So its been slow going for a we while due to actually having to do work but it is now ready for its first Shake down on the track.

This is the first 2 stroke I have built from split cases up. And it will not be the last. New Nitron rear shock on its way and also just a bit of mucking around to fit the Honda RS250 forks I have for it. But as it sits I have the correct weight springs and the front has been completely rebuild and working very well.

The ignitech is on and running but needs fine tuning. That will come when my connectors turn up to hook in the TPS and power Jets from the 38's

Also pipes. At the moment they are the tyga 250 pipes. They are a temp option but look rather nice and give good midrange but not so hot on the peak.

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Looking bloody good Rich.

So how many hours has it taken you to do all the F3 porting and build it up.
First time I've seen mx 38s on a NSR, they must have taken some fitting. Custom parts??

I'm assuming this is a SpeedJunkie partnership / race team. These bikes are going to make superlite/F3 very interesting this year.

[mr bucketracer]

Looking bloody good Rich.

So how many hours has it taken you to do all the F3 porting and build it up.
First time I've seen mx 38s on a NSR, they must have taken some fitting. Custom parts??

I'm assuming this is a SpeedJunkie partnership / race team. These bikes are going to make superlite/F3 very interesting this year.

at least we will see them not like the other one meeting wonders

[richban]

So how many hours has it taken you to do all the F3 porting and build it up.
First time I've seen mx 38s on a NSR, they must have taken some fitting. Custom parts??

Hours. Not sure. At one stage it was all off the hours. But it has been heaps of fun.

Yep late model YZ250 carbs. And some very nice work from sketchy, sorted them out. We were lucky and had some Honda RS250 inlets to copy and (improve on).

I would still like to machine a nice bell mouth onto them but that can wait.


Yes. I think after they prove themselves on the track others will follow for sure.

[Bert]

Hours. Not sure. At one stage it was all off the hours. But it has been heaps of fun.

Yep late model YZ250 carbs. And some very nice work from sketchy, sorted them out. We were lucky and had some Honda RS250 inlets to copy and (improve on).

I would still like to machine a nice bell mouth onto them but that can wait.
Yes. I think after they prove themselves on the track others will follow for sure.

Great work Rich (and Sketchy's work looks great in the flesh).
Only feels like yesterday when the idea was floated.

It really has not taken that long to get them sorted and on track, very impressive; and I'm sure others will follow.

[TZ350]

So Rob. Check out the frame. So its been slow going for a we while due to actually having to do work but it is now ready for its first Shake down on the track.

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Rich, it looks stunning.

[koba]

300 naked_Rich.jpg is getting me horny on a Friday night.

Something is wrong here!

[koba]

Drew, Why?

If the crank is poo wouldn't it be easier improving that within the bounds of a conventional 2 stroke crank?

[Forgi]

Unlike finicky carburetors, with fuel injection there is not the over enriching problems you get when the inlet stream bounces back and forth several times in the inlet tract. Passing the carbs needle jet several times and picking up fuel on each pass. With EFI I don't have to be so conservative with the rotary valve timing and can experiment a little.

Attachment 296434

I have cut the top valve to have the same area but with a soft opening and closing effect.

Attachment 296436 Attachment 296432 Attachment 296435

Soft Opening - Fully Open and Soft Closing........................................... ..................................

@TeeZee: If you just have been testing different types of rotary disc valves, then would it be a huge request to make a dyno test on a 88/88 rotary disc valve?

I'm eager to know exactly what is the difference between the power of a symetric piston controlled inlet port and a rotary disc valve if each and every other pharameters are the same.

Does anybody have such an experience?

[Frits Overmars]

@TeeZee: If you just have been testing different types of rotary disc valves, then would it be a huge request to make a dyno test on a 88/88 rotary disc valve? I'm eager to know exactly what is the difference between the power of a symetric piston controlled inlet port and a rotary disc valve if each and every other pharameters are the same.

They will probably not all be the same, Forgi. A rotary disc usually opens much quicker (= in fewer crank degrees) than a piston port.

[jasonu]

Rich, it looks stunning.

Looks great. I hope it runs as good as it looks.
Where did the pipes come from.

[TZ350]

@TeeZee: If you just have been testing different types of rotary disc valves, then would it be a huge request to make a dyno test on a 88/88 rotary disc valve?

Hi Forgi, I agree, it would be interesting but its not very relevant to my project and its hard for me to do. The std inlet timing for my Suzuki 125 engine is 145/55 so 88 closing is easy, I would only need to cut the leading edge of the disk and it is what I routinely do to get the inlet duration I want. But 88 opening means adding material to the trailing edge, and that would necessitate making new disks.

[Bert]

So Rob. Check out the frame..........

Also pipes. At the moment they are the tyga 250 pipes. They are a temp option but look rather nice and give good midrange but not so hot on the peak.

Looks great. I hope it runs as good as it looks.
Where did the pipes come from.

TYGA NSR250 pipes.
Latest model given they are not hydroformed.