Squish measurement and setting

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JanBros
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Re: Squish measurement and setting

#76 Post by JanBros » Sat Jun 02, 2018 8:42 pm

T.RexRacing wrote:Thanks.
you didn't see the big error I made Image ?
if it runs, you can race it !

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T.RexRacing
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Re: Squish measurement and setting

#77 Post by T.RexRacing » Sat Jun 02, 2018 10:13 pm

BDC. I'm not sweating the details I knew what ya meant.

If I were to argue it's the final evaporation of the incoming charge that contributes so much to dome cooling. But we're not arguing are we? :smt003
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Questo vecchio rz
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Re: Squish measurement and setting

#78 Post by Questo vecchio rz » Sat Jun 02, 2018 11:01 pm

No intent on creating any augment, just some thoughts. I just feel the RZ is a proven darned good motor, that FAR surpassed what it's original designers ever thought it would.
I appreciate reading about 2 stroke development to a point, but in all honesty my interest doesn't venture far past the bikes of the early/mid 90s, as this is pretty much where it all ended as far as us the public being able to buy and ride one.

As far as critiquing the RZ motor, and the basic design of it and all the aftermarket kits, This is where I kinda roll my eyes a little, when it's said the RZ motor/cylinder and variants are crap by holding it in comparison to a totally different motor, developed & designed what .. possibly 30 years after the RZ. The comparison is Apples to Orange's, really not much they have to say, not much at all applies to the RZ.
There by large, not doing nor contributing to the world of the RZ.

As far as the variants of cylinders out there CPI /Athena etc..there capable of delivering huge improvements over the stock cylinders, with tq & h.p levels far exceeding what anyone can even dream of riding.
The power valve(lack thereof) is a issue. Which Mr. Roth and Wobbly had a dream joint venture doing their TSS500, but even they used Yamaha crankcases and CPI cylinders as a base. What would have been welcomed is if they had offered a post TSS meltdown, a Cylinder /Powervalve blueprint for others to enjoy.

What they did as far as RZs was not unlike what anyone does or is doing with aftermarket cylinders as there's only so much that can be done with the basic RZ engine design anything else is just kinda a fantasy or bench racing. What's Ifs and Woulda Couldas.
Anyone who's ever ridden a CPI Banshee or roadracer RZ, knows that the power is just stupid silly fast, and capable of winning vintage championships, if one is so inclined.
Would have been nice if 2 strokes did not fade away and development for a world market RZ continued, but it didn't and it wont, so we are forever married to what the Yamaha engineers developed 40- 45 maybe 50 years ago, which likley is the most popular, capable,durable,exploited 2 stroke motorcycle engine ever, It has done just about everything, Off road,roadracer,karts etc..even to this day one needs a very strong 450-700 cc quad to take down a old tuned Banshee, so to focus on the motors perceived shortcomings, to me is silly and a waste time. However, I'd love to watch what modern engineers and developers could do with a new design platform, but sadly, doubt were going to see much of that either. Especially regarding the RZ, as it's all talk with no action, no one has delivered anything other than folks like CPI etc.. and what we have is tinkering with such cylinders on RZ crankcases. and seeing what so so many racers,enthusiasts, have come up with..that's fun! Basiclly, just keep it real, the RZ motor always was, is and will forever be OLD school. It can't be changed too much from where all the development has landed here...so it is what it is, maybe a little crude, but still a sledgehammer if a motor with killer power potential, likley more power potential than any of us will ever see as far as 2 stroke bike engines.
Banshee (Baja) race bike,+ 2 A Arms,L.E.Ds, Toomey, +4 stroker IMS tank, run flats.
96 GSXR SRAD, Future Yoshimura rep.
85 custom Tri-Z
RZ/YZR bike(project)
86 VFR750 RC24 Merkel replica (project)
Royal Enfield Bullet 500

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JanBros
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Re: Squish measurement and setting

#79 Post by JanBros » Sun Jun 03, 2018 5:32 am

I'm not critiquing the motor, it just is what it is. Just because one loves something, doens't mean you have to be blind for it's flaw's :smt002
I have everything lying on my attic for a couple of years, to try and built a 100BHP 400cc RD motor myself (cause it's the only one I can afford :smt022 ), but other things keep getting in the way, too many projects. Also testing all my ideas for the RD motor first on my MX-moped, much less costly when they fail :smt003
if it runs, you can race it !

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Re: Squish measurement and setting

#80 Post by (F5) » Sun Jun 03, 2018 6:46 am

My 496 is a 100hp engine but sheesh I need to sort the fuse box but it just went bang so needed to start again
496 Cheetah. TSS PVs, PWK35s, Ignitech, RGV(ish) chassis

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Re: Squish measurement and setting

#81 Post by Questo vecchio rz » Sun Jun 03, 2018 4:50 pm

JanBros wrote: Just because one loves something, doens't mean you have to be blind for it's flaw's
Don't ever tell a woman that...lol :smt023
Banshee (Baja) race bike,+ 2 A Arms,L.E.Ds, Toomey, +4 stroker IMS tank, run flats.
96 GSXR SRAD, Future Yoshimura rep.
85 custom Tri-Z
RZ/YZR bike(project)
86 VFR750 RC24 Merkel replica (project)
Royal Enfield Bullet 500

mikee
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Re: Squish measurement and setting

#82 Post by mikee » Tue Jan 01, 2019 4:52 pm

It’s been an interesting read guys
I’ve been dicking about with 2 strokes since I was 10 , near 50 years now , first bike a D1 bantam , pocket money was traded for whitetodd parts , I spent sometime learning things from dr Gordon Blair , basic stuff building on what I already understood , spent my teenage years blowing up yamahas , never looked back since
Got Gordon Jennings book for my 12th Christmas, a g bells book a couple of years later
Still messing about with them , it seems a lot easier to build a big hp motor these days but it’s still just an rd engine
However as a road bike for us old folk it’s just as relevant as it ever was
The point of this was the radiused squish / chamber edge , I did this on the first rd’s i built ,with a basis to the rear of the cylinder , arse dyno says yes , did I “Invent “ this (no) but who did I get the idea from ...
it’s threads/readings like this that inspire curious people onwards
Thanks , keep up the good work

Mike

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