THE MOD SQUAD
The diminutive twin that’s big on character. Here’s how to put hairs on its chest...
How to put hairs on an SV650S’s chest.
BELIEVE IT OR not, Suzuki have produced more than 420,000 SV650s since this incredible little V-twin was first launched way back in 1999. Yes, that’s correct, not far shy of half a million are happily blatting around the roads of planet Earth. What’s the secret to its success? Simple: the SV650 may be small in capacity and stature, but its heart is about as big as they get and in truth its sales success is only a small part of this bike’s amazing story. This budget middleweight has found a niche in the most unlikely of places...
In 2003, the Bemsee MiniTwin Championship kicked off, with the aim of providing cheap and competitive racing that would attract both beginner and experience racers alike. This fabulous series pitted hordes of racers head-to-head on SV650s and it didn’t take long for the grids to swell in size to such an extent that some clubs even ran two or three separate MiniTwin races. Sixteen years later, the class is still very much alive and kicking, and just about every race club in the UK runs their own similar championship.
With such a popular motorcycle there are hundreds of paths to choose from when it comes to performance modifications and enhancements. However, PB spoke to the nation’s experts to set the record straight, so if you have one of Suzuki’s fabulous V-twins in your garage and fancy giving it a bit of spice, here’s the lowdown on what works and what doesn’t...
ENGINE - James Holland “If you have a standard road bike the first thing you want to do is add a full exhaust system as it makes a huge difference and will give you about 4bhp and a chunk more midrange. Cutting the stock system for a can isn’t worth the effort. The only full system you can still buy is the M4, which is stainless steel with a polished aluminium can and costs £700. We do a titanium version if you have a big wallet... There’s no need to remap the bike and for road use; the OE Suzuki air filter is more than good enough, too.
“The next stage depends on the age of your SV. The twin-spark motor can have its ECU remapped, but the earlier bike can’t. On the SV there is an offset between the front and rear cylinder, which makes tuning them hard. Lots of people don’t understand how to deal with this (which is controlled by the secondary butterflies) and a Power Commander doesn’t exploit its full potential. You need the right experience to properly remap one, which is necessary for further tuning.
“Bellmouth kits aren’t worth the effort, and boring the throttle bodies is pointless. For power you need to go big-bore, a cam swap, or both! You need to update the oil pump drive gear in 2003-on bikes (it’s plastic, we do a light aluminium one) and also add a modified sprag clutch gear for reliability before tuning.
“A 2mm over-bore gives you 80bhp, a fat torque curve and reliability for about £800 ride-in/ ride-out, and is beautiful on the road. Add a set of cams and you get even more power and torque. They also work on a stock motor and cost £450 for the cams plus fitment (£150 or so plus dyno set-up time)
CHASSIS - Richard Adams
“We see a lot of SV650s for both racing and road. As a standard road bike the suspension is very cheap, but as you don’t have too much power to deal with, that’s not a massive issue.
“The shock’s spring rate isn’t bad, a touch soft.
‘A 2mm over-bore gives you 80bhp, a fat torque curve and reliability, for about £800 ride-in/ride-out’
However its damping is very poor and that’s where the problems start. Initially it’s very sticky in its stroke, which makes it harsh, but once you get through this it’s like a pogo stick. There’s not a cure for it: so you are best investing in a quality aftermarket unit.
“The forks are an old, cheap, damper rod system. There is only a little compression damping to try to control the spring. The springs are too soft and the system lacks rebound damping, causing the forks to dive and then pop back up again. Some people add thicker fork oil as a cheap fix, but this only serves to make them harsher.
“We do a spring kit with different oil for the forks, but this is always a compromise and while it is better and only £120, it’s not a true fix. If you want to truly improve the bike, our £660 cartridge kit is excellent and has high/low-speed compression damping with
separate compression/rebound damping. Fit this and the forks become far more progressive and linear in their action.
“One tip I would give for sporty riding is to raise the rear of the SV, which makes a big difference. Some try this through using a longer GSX-R shock, or fitting new tie bars, but if you buy a quality aftermarket unit it should have an adjustable ride height and is a better long-term route.”
James Holland also added: “While you can stick in a GSX-R front end, there are issues. The GSX-R models have shorter forks than the SV, so you need to add fork extender caps if you use GSX-R yokes, and the various GSX-R models have different offsets. And you also lose the SV’s speedo drive from the front wheel. Honestly, for the road, you are better off adding a fork cartridge kit to the stock forks. And the same goes for the shock – people do fit shocks from other bikes, but by the time you revalve it to make it work, you may as well have bought a quality aftermarket shock.”
BOLT-ONS – Giles Harwood
“Older bikes really benefit from an upgrade to their brakes and we sell lots of Brembo SC pads (£89 for four), which are a sintered pad straight out of Brembo’s race department that many racers, as well as road riders, use to give the two-piston sliding calipers a bit more bite. Add a set of braided brake lines (three lines for the SV, HEL Performance lines cost £78 with brake fluid included) and for under £200 you will have far better brakes. You can also add Pazzo CNC-machined adjustable levers for £169 in a range of colours and even spec them up to include folding or stubby levers for £30 extra, which smartens up the basic-looking controls.
“Crash protection is always a good seller for the SV, which hints at its popular use as a commuter/beginner bike, at £76 for a set of frame protectors. Double bubble screens are a popular addition for just £58. Finally, and this is a great mod, you can get a plug-and-play GiPro digital gear indicator for £105. Nothing is excessive in price for the SV and it is a relatively cheap bike to customise and improve through some easy bolt-ons.”
NEXT MONTH: 2009 Kawasaki ZX-6R – the mini green meanie...
1 ANGLES OR CURVES? The SV650 was originally launched in 1999 with a curvy, mini-TL1000Sstyle frame and bodywork, and a carbureted motor. 2003’s secondgen model had an angular frame and bodywork, plus fuel injection. 2 DETAIL UPDATES The ‘angular’ SV was updated in ’04 (engine internals, new crankcases, fork internals). Black frame paint superseded silver in 2005. ABS was offered as an option for 2007, and the motor went twin-spark
Good old-fashioned round-profile exhaust. Aftermaket options are many
Standard shock is best replaced by an aftermarket unit with a quality action
3 EXHAUST STUDS Always check the front exhaust studs if you are looking at fitting an aftermarket pipe. They are in direct line of fire from road grime and often seize solid. Drilling them out and re-tapping is a groin-ache. 5 MISFIRE Water gets trapped in the front cylinder spark plug hole, attacking the plug and cap, eventually causing a misfire. There is a drain on the cylinder to allow water to escape; simply push a wire up it to keep it clear. 4 GEARING You can replace the S model’s smaller 44-tooth sprocket with the naked N’s larger 45-tooth one to add a bit of spirit to its acceleration. The speedo’s reading is unaffected as it is taken from the front wheel.
Spring kit is a budget approach, but will pay some dividends
There are few better sports-style middleweights to cut your teeth on
Twin sliding piston brakes can be improved with new pads and braided lines