Suzuki SV650 1999 Racebike

[lowscorts]

The Blue line is before I started tuning the motor
The red and green are different cams, spec at this stage:-

Wiseco 700cc kit
K3 inlet cams K2 inlet cams fitted to exhaust (red line, std K3 = green)
Flowed heads with cut back seats and multiangle valves
Micron Headers with Hindle high link pipe
BMC race stg2 filter
Dynojet kit, dj175 mains, needles groove 2.5 (base setting, not setup)


This was a powercheck after the motor was first run in on the dyno, didn't realise he used Din correction until I got home


And this is what £750 of 41mm Keihen Flatslides give you over CV's



Same setup But with M4 system, modded 56mm can, Pace oversized rad and oil cooler


After a bit of extra setup at PDQ as it was a bit fierce on the roll on with the throttle pumps


Current setup is as per first list with:-
41mm Flatslides with different length bell mouths to reduce stand-off between cylinders, no filters
+1 larger main air correctors with 180 hex mains
M4 large diameter race system wrapped, with 57mm outlet and Remus trapizoidial Ti can modded with larger outlet and 57mm core
Pace oversized Rad and oil cooler.

It made 64hp std with a race system and DJ kit, It now makes just over 91hp with 55ftlb of torque

I did everything on the engine apart from flowing the heads and boring the cylinders and as its my first twin that I have tuned I'm pretty chuffed, especially as it Won me the Thunderbike championship last year with 1 round to go

[Lee S]

Those power figures are impressive, especially considering most of the work you have done yourself. At Uni we are building a single seater racecar using the Aprillia RVX 550cc Twin. Cracking engines, 32kg including gearbox and dry sumped! Do you have any tips for tuning twins? I think all our past cars have used 4 bangers so not upto speed on V Twins!

[lowscorts]

oops forgot I posted this

The thing I found with the twin is they dont react to normal IL4 tuning, I kept it simple, its running 1mm of squish and about 13:1 comp, SV's suffer from hotspots in the heads so its better to skim the barrels.

The RVX motor is a bit of a different animal as it is built along the lines of the high revving singles.
Dave at HM racing has done a few of these now with good results so maybe worth enquiring on their packages for some ideas of spec