SPEC II rpm band

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thumper580
Posts: 89
Joined: Sun Jul 24, 2016 3:02 pm
Location: Virginia USA

SPEC II rpm band

#1 Post by thumper580 » Tue Nov 28, 2017 6:26 pm

What rpm band are the 1986 era SPEC II pipes designed for??? mid range or more top end. Thanks.
1985 RZ350
2000 Ducati 996S
WERA V2 National Champion

hondaror
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Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: SPEC II rpm band

#2 Post by hondaror » Tue Nov 28, 2017 10:36 pm

They are all upper end. You need a big bore kit before you want to think of midrange.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

thumper580
Posts: 89
Joined: Sun Jul 24, 2016 3:02 pm
Location: Virginia USA

Re: SPEC II rpm band

#3 Post by thumper580 » Tue Nov 28, 2017 11:02 pm

You confirmed what I thought, thanks.
1985 RZ350
2000 Ducati 996S
WERA V2 National Champion

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Questo vecchio rz
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Location: Reconquista of California

Re: SPEC II rpm band

#4 Post by Questo vecchio rz » Thu Nov 30, 2017 5:44 am

You can Email Gary and ask him, He may take awhile to respond but he will explain all his designs.

I met him in 1985 due to the fact I had the 1st (Calif) RZ he was able to aquire, he it used car it to compare vs his 49 state racebike/test bike.
I later had a set of the 85-86 pipes on my RZ, I will tell you that the early versions definitely fell short of the performance of Toomeys, especially down low and mid range, when fitted w Toomeys the Spec 2 equipped bike always fell 3-4 bike lengths behind under full throttle acceleration, I don't remember them matching the Toomeys in top end either, but sustained high RPM use on a race track, is likley where he had them tuned to perform, and on a road course the benefit of his design likley gave good results. In the US, many if not most race RZs utilized either Toomeys or Spec 2s. Gary's pipes were built fairly durable as well, albeit marginally heavier.
Gary is a true engineer, math calculations, and tests many different designs he knows mist there is to know after almost 45 years of Yamaha twins.
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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