ESE's works engine tuner

[Niels Abildgaard]

True about Jean Bertrand being a genius; not true about his V2-engine having a common crankcase. The separation between the left and right cases was taken care of by the center part of the crankshaft. It was grooved; the groove carried a 'piston ring' that expanded when fitted and then was stationary in the cases, forming a labyrinth seal.
Attachment 319630Attachment 319632Attachment 319631Attachment 319629

V4 and V6 outboards have had crancases separated with discs for years.
The real solution for a V2 twostroke crank can be a Hirth coupling in the midle of the crankpin.
Jan Thiel has mentioned that someone wanted to put a 24 mm crankpin in the 125.
Will that destroy the needle cage in no time or 5 minutes?

http://www.ebay.com/itm/WSM-OUTBOARD...ZV1a0v&vxp=mtr

http://i.ebayimg.com/images/g/5owAAM...eX/s-l1600.jpg

[Niels Abildgaard]

Has a common crankcase ever been tried on a 90 degree? Someone with better knowledge than me (like 99% of the people in here) that has a good guess if it will work well or not?

A 60 degree V2 common crankcase was tested and ran ,but no pipes and model diesel where there is next to no energy in blowdown.

http://www.homemodelenginemachinist....ad.php?t=22760

[wobbly]

The SwissAuto/Pulse 500 90* V4 had a common case for cylinder pairs, but these were set on a flying web with pins sitting at 90*
apart as well.
Thus both pistons were rising and falling together.
Worked very well once a zillion Euros were spent on exotic materials for the crank.

Re the thermostats - both the Rigetti in usd and the one Frits linked to in Euro, work out at the same price in NZ dollars then freight on top.
What they dont tell you is the price for a replacement internal element,the Rigetti is 30 something Euro,if you needed one I will
replace it for the cost of the courier.
Opening at 45*C means the normal running temp is over 50*,not so flash in a racing 2T for best power.
So with the interest shown here and in PMs I will talk to Mr Knobbly Knees today and get a batch under way.

[Flettner]

The SwissAuto/Pulse 500 90* V4 had a common case for cylinder pairs, but these were set on a flying web with pins sitting at 90*
apart as well.
Thus both pistons were rising and falling together.
Worked very well once a zillion Euros were spent on exotic materials for the crank.

Re the thermostats - both the Rigetti in usd and the one Frits linked to in Euro, work out at the same price in NZ dollars then freight on top.
What they dont tell you is the price for a replacement internal element,the Rigetti is 30 something Euro,if you needed one I will
replace it for the cost of the courier.
Opening at 45*C means the normal running temp is over 50*,not so flash in a racing 2T for best power.
So with the interest shown here and in PMs I will talk to Mr Knobbly Knees today and get a batch under way.

No need, I read that, it's on the white board, thanks.

[Frits Overmars]

The SwissAuto/Pulse 500 90* V4 had a common case for cylinder pairs, but these were set on a flying web with pins sitting at 90* apart as well. Thus both pistons were rising and falling together.

The Swissauto's V-angle was a bit more than 90° Wob. But how much more? According to their specs it was 108° but the picture tells a different story....

[husaberg]

The Swissauto's V-angle was a bit more than 90° Wob. But how much more? According to their specs it was 108° but the picture tells a different story....

I am not sure if it changed at all during its life but the early ones eyeball at around 108 degrees
http://www.kiwibiker.co.nz/forums/al...p?albumid=4833
plenty of pics and stuff I accumulated on the Swissauto
From Memory the Honda NSR500 was 112 for most of the time at least (87 on)

Yamaha altered their v angle a number of times both narrower and wider.

V4 and V6 outboards have had crancases separated with discs for years.
The real solution for a V2 twostroke crank can be a Hirth coupling in the midle of the crankpin.
Jan Thiel has mentioned that someone wanted to put a 24 mm crankpin in the 125.
Will that destroy the needle cage in no time or 5 minutes?

]

Honda for years ran both 24mm and 25mm pins in the 250's and 125's. But bigger will have a propensity to skid more and be heavier.

[lodgernz]

Anyone got a source for CFK which is suitable for reed valves? The only source I got at the moment are the Polini plates - but they are quite expensive compared to other CFK plates on ebay...
Cheers
Tim

Boyesen has CF reeds for many engines

[peewee]

wob few questions. the twins with single head use a bigger diam water hose than most engines. would it be to much trouble to not machine the nipples down so far on the one I was planning to buy, so the thermo would fit proper in the larger hose ? I cant recall the hose size and I don't have any spares laying around

what do you think of seperate two piece heads with orings instead of the single one piece with metal gasket ? or does the single offer some stabilization of the cylinders

[husaberg]

+1 Vinamold

Anyone got a source for CFK which is suitable for reed valves? The only source I got at the moment are the Polini plates - but they are quite expensive compared to other CFK plates on ebay...

Cheers
Tim

http://www.treatland.tv/SearchResult...rch=reed+sheet
http://www.ebay.com/itm/CARBON-FIBRE...-/401038860729
http://www.spi-parts.com/feuille-fib...100x100mm.html
https://www.beedspeed.com/reed-petal...a63ataqea40db6
http://www.ve-uk.com/general-and-uni...eds/0/malossi/
http://scootertuning.ca/en/11_doppler
http://www.mcmaster.com/#standard-ca...heets/=115p3lo


Fibreglass reeds according to the web are make from G10 sheet
http://www.matweb.com/search/datashe...assnum=PGLAM04
http://www.professionalplastics.com/G10FR4SHEET

[Sketchy_Racer]

Dont mention the word "fudge" or Neels will cancel your software licence , he hates the word with a passion.
OK, so here we go with getting the correct combustion parameters into your sim.
Firstly be aware that the squish geometry is one of the inputs that the code uses to generate the parameters that govern the combustion numbers.
So this must be optimized or at the very least close to what the engine is/will be running.
Firstly enter the combustion page with the default entries - I have shown that page for the TZ400 engine, along with the actual ignition timing.
Then run the sim, and if you get any obvious area of deto at one rpm point, then that can usually be fixed by pulling some timing.
If on the other hand you get deto all over the shop, then something is very wrong with the compression for the fuel entered, or the stinger is way too small.
What I am saying is get the sim working reasonably happily initially, using the defaults and Burnrate Prescribed.
Then - change to Turbulent Model with the current setup and save that Combustion change - but you dont need to rename it.
Run the sim, and call that run say TurbMod,this will take forever, as its now actually calculating what is happening in the chamber.

Once its done open the Post Processor,and select Performance and Efficiency.
Open the engine files you are working on, and select the last sim run called TurbMod,now the page with the parameters you want to be looking at will open, and
on the RH side is a Write Combustion File radio button.
Click that and enter a new name for that file, like in my case TZ400 Reed TurbMod, and enter the other parameters needed.
This will then save to the 2Stroke folder with that new name.
Then when you reopen your EngMod Dat2T engine sim, you can select Existing Combustion Data, and select that newly named file.
This will now have all the correct Wiebe functions etc for your setup.

Very occasionally the new file will crash, due to one of the calculated numbers being out of range ( like duration at say 100+ on one line ) if so ask Neels to look at your packed up file.
You are not annoying him, as seeing the error helps him refine the code each time to prevent it occurring in similar circumstances.
Now you have the correct numbers, you can save the file with Burnrate Prescribed again, and it will now run as fast as before - just alot more accurately.

Thanks for the write up Wobbly, I'm running through the sim now will post results soon!

-Sketchy

[nick gill]

Sorry to digress from the discussion. Came across this on Fecesbook
As yet unexplained. Any ideas chaps?
CPS + hall sensor is obvious. Ambihelical confabulator?

[Yow Ling]

its the gear change mechinisim on a Gnani engine , same as Jan Thiel used on the Jamathis

[TZ350]

Chambers has been preparing the 13+ hp number 2 bike for the next Mt Wellington round and the GP at Tokoroa. At least we are having more luck with this than the number 1 bike. Team GPR, C U at Tokoroa.

[mr bucketracer]

Chambers has been preparing the 13+ hp number 2 bike for the next Mt Wellington round and the GP at Tokoroa. At least we are having more luck with this than the number 1 bike. Team GPR, C U at Tokoroa.

who is chambers i must ask? heres mine (-;

[mr bucketracer]

the bike