ESE's works engine tuner

[Grumph]

A few years back Kevin Grant (well known Britten owner) apparently had all the 400's here in NZ - I don't know if he still has them.
Talking to him he was quite keen to get one running and bring it South for the Sound Of Thunder meeting but it hasn't happened.

Frits - you should be happy they're as far away from you on the planet as they can go....

[husaberg]

You have no idea what you're asking of me. I refrained from reading the above articles because I want to keep my good mood. But OK....
The 400 cc twin was entirely Witteveen's idea. He built it in cooperation with Franco Moro (the same glorious cooperation that produced the Maxtra / Haojue 125...). When they realized that 400cc wasn't enough to beat the 500 cc fours after all, they made the pistons bigger and bigger, resulting in a more and more oversquare engine with more and more thermal problems.

Sorry Frits it wasn't intended to be a mood killer. I had only just read the article and sensed some stuff in it relation to either a lacking of confidence or competence. I had never got the same feeling from other articles relating to the 250. So I will be assuming the later?
Googled those bikes you mentioned. a few teething problems and a rider revolt and a sacking http://www.crash.net/motogp/picturea...47765/1/photos

Upside down engine i am assuming the Rumi layout (I am sure you are a little familar with that as well I guess see pic 5)i had posted earlier i thought it was quite trick until i looked at a 1988 YZR500 or for that matter a 1988 Aprilia v twin naked and realised the upside down engine was just so plain logical.The beauty of hindsight for me, Genius for the designers. Who did the Chassis for it?
oh ok Nico Bakker.http://2stroker.createforumhosting.c...iel-t2652.html

Grumphs bit. I shouldn't be that surprised knowing of Kevins collection of exotica. But i was about the Aprilia.

[Kickaha]

Upside down engine i am assuming the Rumi layout i had posted earlier i thought it was quite trick until i looked at a 1988 YZR500 naked and realised the upside down engine wasn't innovative after all.

I hadn't seen them before but I helped a friend build an upside down NSR250 in a Kart with the gearbox cut off driving through a fluid coupling although that was late nineties

[wobbly]

As an indicator of the relative genius of the design team, look at the intake on the Rumi - an FCR carb with dead straight manifold.
Then look at the Maxtra, balls up par excellence.
I had a job interview with Mr Witteveen at P.I when McWilliams put the Aprilia on pole,short of the story was I didnt take the job, wish Frits had done the interview and then I would maybe have got to meet Jan.

[Frits Overmars]

A few years back Kevin Grant (well known Britten owner) apparently had all the 400's here in NZ - I don't know if he still has them. Talking to him he was quite keen to get one running and bring it South for the Sound Of Thunder meeting but it hasn't happened.
Frits - you should be happy they're as far away from you on the planet as they can go....

Maybe you could bring them just a little bit closer - isn't there a deep spot in the ocean somewhere?

[husaberg]

Maybe you could bring them just a little bit closer - isn't there a deep spot in the ocean somewhere?

Couldn't you just slip on in a 250 engine? I hear they went kind of ok with one in them? (for a 2 stroke.)
I assume the chassis is nearly identical. Are they?

Couple of Cobas.
JJ-Cobas with Autisa engine (designed by Jan Thiel) 1985

Seen this today regarding Bill Buckley.
http://www.kiwibiker.co.nz/forums/sh...0-Bill-Buckley

[Grumph]

Maybe you could bring them just a little bit closer - isn't there a deep spot in the ocean somewhere?

From what he told me, when he asked about buying them as a job lot, the response was along the lines of "New Zealand ? Yes. that should be far enough away....." Whoever he talked to at the factory just wanted to get rid of them.

Your bad luck the container reached here instead of falling overboard.

[Brian d marge]

Couldn't you just slip on in a 250 engine? I hear they went kind of ok with one for a 2 stroke.
I assume the chassis is nearly identical. Are they?

Couple of Kobas.
JJ-Cobas with Autisa engine (designed by Jan Thiel) 1985

Kind sir , please stop posting naughty pictures on the internet , my old heart hasn’t seen this much action since Angela Peabody showed me her "etchings"

Stephen

must have a lay down ......

[husaberg]

Kind sir , please stop posting naughty pictures on the internet , my old heart hasn’t seen this much action since Angela Peabody showed me her "etchings"

Stephen

must have a lay down ......

The Japanese sure do like their cartoon naughtiness. I guess the fetish has er...rubbed off on you to.
Tally ho and tootle pip.

Add Honda RS125 stuff later.... It is after all the for many a day of worship and I bet if he was into bikes (GOD) he would have rode a Honda.

[TZ350]

EngMod2T





I had previously built up an EngMod2T model of my existing motor that pretty much matched its real life dyno graph.



And then added a Pipe designed by Frits, the old plenum and my triple port cylinder and got 40+hp. It exists in theory, now could the race be on to see who can make the first Bucket to touch 40rwhp in reality!!!!

[koba]

EngMod2T

Attachment 253013



I had previously built up an EngMod2T model of my existing motor that pretty much matched its real life dyno graph.



And then added a Pipe designed by Frits, the plenum and my tripple port cylinder. Could the race be on to see who can make the first 40rwhp Bucket!!!!

Fecking impressive.

Poor 1970's commuter-bike crank... 13500 sounds like a big ask.

[TZ350]

Poor 1970's commuter-bike crank... 13500 sounds like a big ask.

Phenolic main brgs with RGV250 rod assembly has proved reliable so far ....

[koba]

I've been playing with simulations a bit.

In MOTA I've input a model of my current engine, as mentioned earlier It seems around right but perhaps a little optimistic on the outright horsepower.

Here are before and after curves of the current plan.
Subject to change as I learn more.


I found I can get much higher numbers but I think it may be a quirk of the maths behind the sim or something. I don't trust it to deliver in real life.



I'm especially mindful of wobbly's comments (ages ago) regarding "sucking real hard on crappy transfers".
I'm probably going to spend a bit of time working out crank case volumes because while I know it is a bit old fashioned I know my motor is too!

[koba]

Phenolic main brgs with RGV250 rod assembly has proved reliable so far ....

True, you guys have done very well when it comes to reliability. The odd pop, but that is to be expected considering the nature of your endeavours.

I've been meaning to ask, has that Belzona remained attached to the piston?

[TZ350]

You see what I mean about Mota over stating it but I think you will fined the rpm and the shape of the curve will be pretty well right.

True, you guys have done very well when it comes to reliability. The odd pop, but that is to be expected considering the nature of your endeavours.

I've been meaning to ask, has that Belzona remained attached to the piston?

Yes, the Belzona is still there ... and yes, I think the cranks can be made reliable with original Suzuki RGV rod kits and decent main brgs, the same could be done with TF/TS's and then they should be good for 13,000 + too.