2 stroke porn

[zimm]

isnt this just lovely ?




if i could spare the cash i'd have it just to look at.

[RedexRobB]

Not sure what it is if im honest, something tells me its a Yamaha. Ahh looked carefully and saw the 'yamaha corse' badges

[crushedlizard]

That's a 250cc right? Where are the exhausts/spannies though?

It is a lovely bike. I struggle with anything but USD forks though - old style look like knee-high socks

[RedexRobB]

i suspect they exit out the back and are hid underneath the seat panels.

[zimm]

its a yamaha TZR-250 3MA reverse cylinder,

its a parallel twin with the carbs in front of the cylinders and the exhausts exiting in a straight line under the seat, very very closely related to the tz-250 gp bike of a couple of years before

60bhp, 50% more torque than a zxr400, 135kg

[RedexRobB]

60bhp, 50% more torque than a zxr400, 135kg

Bloody hell, that thing must be lethal!

[crushedlizard]

I was wondering how you could squeeze an expansion chamber under the bike and get away with extending the pipe. That is such a cunning way to mount the engine/exhausts.
I'm probably being really stupid here, but how do you reverse the engine? Or has the engine always been orientated with exhaust ports to the rear?
I know in theory 2T engines can be run in reverse but I thought that applied to very simple models.

[zimm]

I'm probably being really stupid here, but how do you reverse the engine? Or has the engine always been orientated with exhaust ports to the rear?

its just the cylinders that are "reversed" mostly strokers are a normal configuration, but the 3MA was the most developed parallel twin made, by the time it was launched everything else was a V twin (KR1-S doesnt count as it was an evolution of the KR1 which was already a couple of years old)

i believe yamaha did it for a number of reasons, exhaust packaging being the obvious one, and primitive ram-air the next (although only on the TZ's, the airflow on the 3MA is a bit convoluted)

[zimm]

60bhp, 50% more torque than a zxr400, 135kg

Bloody hell, that thing must be lethal!

aprillia rs250 would be quicker, but i know which i'd rather have

[Scott221]

I was so close to buying a tzr 125 last week. I mean just look at this...

[zimm]

lovely arent they .. i think adamzxr(?) on here is selling his ..

tzr250 3xv v-twin (250 version of above)





if they werent restricted to 45bhp (and almost impossible to de-restrict) and uber expensive (that ones on ebay for 4 grand !!) i'd most definitely have one

given the above, i want a 3ma

[crushedlizard]

its just the cylinders that are "reversed"

Oh of course, you mean it's just the barrels that are rotated 180º (and I suppose pistons)? I think I remember someone wanting to do that on an Aprilia RS125 so they could have an underseat exhaust without choking all the power out by lengthening the pipe. But it couldn't be rotated for one reason or another.

Anyway, awesome setup. Where did you find the pics?

[zimm]

its on ebay for £1020 .... and im VERY tempted ...

anyone want to buy a couple of ZXR's so i'd have space ?

[rene]

when i finaly get my own space im going to fill it with 2 pokes. Most likely starting with a TZ250 . The engines just fit bikes so perfectly compaired to 4t's

[Gemini]

some more for sale..

http://cgi.ebay.co.uk/TZR250-TZR-250-3X ... .m14.l1318

http://cgi.ebay.co.uk/YAMAHA-TZR-250-3X ... .m14.l1318

http://cgi.ebay.co.uk/Yamaha-TZR-250-3M ... .m14.l1318

althought for me, the best and rarest 250 is this..

http://cgi.ebay.co.uk/HONDA-MC28-SP-NSR ... .m14.l1318

gem