Search found 30 matches

by oldjohnno
Sat Aug 20, 2016 7:37 am
Forum: 2Stroke Tech
Topic: Flow management through reeds
Replies: 22
Views: 10346

Re: Flow management through reeds

Jeepers, 15 or 20 cycles to get mixture up the transfers? Really? No. You can build a fresh engine without a drop of fuel in it, bolt on the carb, kick it twice and it's running. The cylinder has enough mixture in it to fire and run after 3 or 4 revolutions. Must be time for some maths revision , m...
by oldjohnno
Fri Aug 19, 2016 7:02 am
Forum: 2Stroke Tech
Topic: Flow management through reeds
Replies: 22
Views: 10346

Re: Flow management through reeds

That looks very much like a current Stihl technology that uses two carb throats in a staged arrangement. The primary is conventional while the secondary is just a butterfly and is air only. It's probably not quite accurate to call it a stratified charge but the idea is that the porting is arranged s...
by oldjohnno
Mon Jun 13, 2016 9:49 am
Forum: 2Stroke Tech
Topic: Race fuels,methanol,e85. settings and blow ups
Replies: 8
Views: 6442

Re: Race fuels,methanol,e85. settings and blow ups

2TInstitute wrote:E85 is half way to a methanol setting ,the old petrol to methanol conversion factor was 1.5X with e85 it's about 1.25X
2T, how does the cooling effect of e85 compare with that of straight methanol?
by oldjohnno
Sat Jun 11, 2016 11:18 pm
Forum: 2Stroke Tech
Topic: Race fuels,methanol,e85. settings and blow ups
Replies: 8
Views: 6442

Re: Race fuels,methanol,e85. settings and blow ups

I've had limited experience with methanol. One thing I'd stress is checking the available fuel flow of the entire system from the tank through to the needle and seat. It's not uncommon at all to find that it simply can't keep up with demand so it's easy to cook pistons even with appropriate jetting....
by oldjohnno
Sun Jun 05, 2016 1:32 pm
Forum: 2Stroke Tech
Topic: Liner suppliers
Replies: 4
Views: 4787

Re: Liner suppliers

2TInstitute wrote:Use Arrum plating at your peril.

If your making a liner making the liner out of 6061 aluminium and having it nicasil is much better(and cheaper) than a thick iron liner.
I've heard the Aurum horror stories, will be giving them a wide berth...
by oldjohnno
Sat Jun 04, 2016 10:20 pm
Forum: 2Stroke Tech
Topic: Liner suppliers
Replies: 4
Views: 4787

Re: Liner suppliers

OJ, were you looking for a new, or big bore Fe sleeve, a custom Al unit, or re-plating the existing bore? Tried this mob? http://www.nickesil.com Or if its a sleeve you want, these blokes seem fairly reasonable price-wise, - even taking the exchange rate into account.. http://www.advancedsleeve.com...
by oldjohnno
Sat Jun 04, 2016 8:46 am
Forum: 2Stroke Tech
Topic: Liner suppliers
Replies: 4
Views: 4787

Liner suppliers

Any recommended blank liner suppliers in AU (or anywhere else for that matter)? I've used Electrosil before but they're bloody expensive..
by oldjohnno
Wed May 25, 2016 8:49 pm
Forum: 2Stroke Tech
Topic: Block connectors - sources?
Replies: 9
Views: 5542

Re: Block connectors - sources?

You can get auto wire from ebay, as well as high quality connectors like Weatherpack and Metripack and the tools to suit.
by oldjohnno
Mon May 23, 2016 8:31 pm
Forum: 2Stroke Tech
Topic: Flow management through reeds
Replies: 22
Views: 10346

Re: Flow management through reeds

BRG1200 wrote:Jeepers, 15 or 20 cycles to get mixture up the transfers? Really?
No. You can build a fresh engine without a drop of fuel in it, bolt on the carb, kick it twice and it's running. The cylinder has enough mixture in it to fire and run after 3 or 4 revolutions.
by oldjohnno
Tue Apr 19, 2016 7:08 am
Forum: 2Stroke Tech
Topic: Myths, old wives tales and bullshit that just won't die
Replies: 22
Views: 10158

Re: Myths, old wives tales and bullshit that just won't die

back in the day the 350 yams were as fast as the 70s/80s 750s.... yeah right. they were quick, but not that quick.... The little yams did win quite a few races over much bigger bikes, but it wasn't because they were faster. The tyre technology of the time simply couldn't keep up with engine perform...
by oldjohnno
Fri Apr 15, 2016 6:37 pm
Forum: 2Stroke Tech
Topic: Myths, old wives tales and bullshit that just won't die
Replies: 22
Views: 10158

Re: Myths, old wives tales and bullshit that just won't die

Nothing at all to do with bikes or two-strokes but the Z-Crank is just too good to not share.
Image
by oldjohnno
Fri Apr 08, 2016 6:55 am
Forum: 2Stroke Tech
Topic: Myths, old wives tales and bullshit that just won't die
Replies: 22
Views: 10158

Myths, old wives tales and bullshit that just won't die

well bring forth the discussion, the only good one I can think of is a good collection of things that are complete bullshit and old wives tales that get bandied around year after year. Next is a shitlist of truly shit products that we got sucked in/almost sucked in by the hype. OK I'll start. What ...
by oldjohnno
Fri Apr 08, 2016 6:44 am
Forum: Website Help & Suggestions
Topic: Tech Section
Replies: 7
Views: 4752

Re: Tech Section

well bring forth the discussion, the only good one I can think of is a good collection of things that are complete bullshit and old wives tales that get bandied around year after year. Next is a shitlist of truly shit products that we got sucked in/almost sucked in by the hype. This could be intere...
by oldjohnno
Mon Mar 14, 2016 6:18 pm
Forum: 2Stroke Tech
Topic: Piston Coatings
Replies: 10
Views: 6662

Re: Piston Coatings

Thanks James, that's exactly the sort of info I was looking for.
by oldjohnno
Fri Mar 11, 2016 9:44 pm
Forum: 2Stroke Tech
Topic: Carb slide coatings
Replies: 8
Views: 5495

Re: Carb slide coatings

Mikuni flat slide stuff - TM, TMX, HSR etc - is hard anodised black, maybe this is something similar. It's quite possibly original; the OEMS carbs were often specced differently to the aftermarket carbs of the same type. I liked the old VMs with the chromed brass slides - smooth as silk. A bit off-t...