Honda VTR - Long Term Update

My prayers were answered. After pleading with Honda to allow AMCN's long-term VTR1000 SP-1 to remain in our clutches just a little longer, Honda concurred.

And not only that, but Honda booked me and the SP-1 in for a ride-day at Phillip Island with the Honda Rider's Club crew - and supplied a 'hotted-up' SP-1 of its own for a side-by-side evaluation. It's a tough life, this journalist lark...

It wasn't all peaches and cream however, as not even Honda could organise the weather, which rivalled that of the jetski debacle that doubled as the round of the 2001 world Superbike title.

It would have taken more than an irate Troy Corser to keep me from venturing out on the track though - it wasn't that bad, apart from the wind and the rain and the cold...

THE RED BARON
The progress of AMCN's 'Red Baron' SP-1 has been well plotted in these pages over the last 12 months; just refer to the panel on page 55 to see wotzbeendun.

The idea had always been to set the bike up as a bit of a track weapon, with road considerations falling into a distant second.

Surprisingly, given those intentions, we finished with a bike that is equally at home on a fast, twisty roadride as it is on the race track - though admittedly, the faster you go, the better it feels.

The SP-1 Honda supplied for my day at the Island, known forthwith as the 'Silver Bullet', has been progressively developed with a corresponding brief - more ride-day focussed than anything else - but it has used different products/methodologies along the way.

All this development isn't to say that the stock $21,690 SP-1 isn't a capable machine in its own right, but it is definitely a bike that responds well to tuning.

One area in particular that rewards some active attention is the PGM-F1 fuel injection - here's where the two bikes were led down completely different paths, albeit with the same aim.

Th Red Baron scored a Dynojet Power Commander 3R, as detailed in Vol 51 No 23, which over-rides the stock system. The Silver Bullet retains the standard injection, however, with some airbox, cam and exhaust mods to suit.

The airbox mods are easy 'do-it-yourselfers', but due to EPA regulations are for the racetrack only.

IN A FLAP
The first step involves disabling the 'flapper' valve that resides in the distinctive air intake duct.

The valve's job is to help the SP-1 pass the EPA air intake noise test. As such, it closes at 5500rpm, reducing the air duct's size by around 65 percent, before re-opening at 6500rpm.

Naturally this sort of carry on creates a flat spot, in between 5000rpm and 7000rpm in this case. Disconnecting the vacuum line to the flapper, however, allows the valve to remain open throughout the rev-range, thus eliminating the flat spot.

Take a gander at the dyno runs recorded on the modded bikes (same time, same day) at PTR's workshop in Wantirna South (Vic), and the dip in the AMCN bike's power and torque curve at the 5000rpm mark is evident, while the Silver Bullet is dip free. More on the dyno readouts later.

Next step is to reap more flow from the standard air filters by removing the fine wire mesh surrounding the standard jobbies. The Silver SP-1 was also sans air duct mesh, perhaps the reason the sodden seagulls gave me a wide berth at the Island - the bared duct could swallow them hole.

The Moriwaki stage one cams in the Silver Bullet are there to improve mid-range power, the installation of which involves simply replacing the standard bump-sticks.

BREATHE MAN, BREATHE
Exhaust duties are left to a ludicrously expensive ($5354.95!) Akrapovic full exhaust system, complete with carbon-fibre end-cans. The cost was rationalised somewhat when I spotted the tiny HRC insignia on the system.

The set-up is genuine Honda Racing Corporation, - ie rare and obviously expensive. Honda has one system left in stock, should you have the readies...

The reason for all that fiddling is to improve on the standard bike's throttle response, which is a little snatchy and imprecise at low speed, as well as the dreaded fuel-injected abruptness in the throttle on/off area.

The other Silver Bullet mods are purely cosmetic, and they work an absolute treat. The decals spice up the already smick-looking Honda Europe silver paint scheme, particularly the pin stripe on the wheels.

The suspension has been left untouched, although Honda employee Allen Jeffrey, the bloke charged with the Silver Bullet's development, has spent a bit of time setting up the standard suspenders.

So, with the bikes at the end of their parallel development stage, both embarking on different routes to arrive at the same goal, what works and what doesn't? Finding that out is what race tracks are for - even wet, windy, cold ones...

GOOD DAY FOR DUCKS
Both bikes were fitted with the same excellent Pirelli MTR21 tyres and retained their standard gearing, which provided a scientifically pleasing 'control' for the comparison.

The first difference I noticed between the two bikes was the steering. Even at the heavily reduced pace I was travelling at, thanks to the weather, the Red Baron won out in the steering stakes.

While this is to be expected due to its Shocktech-tuned suspension, I was surprised how much more precisely it steered than the Silver Bullet at those relatively reduced speeds.

Comparing anything else suspension-wise was nigh impossible, as I was using only around two-thirds of the suspension stroke at the reduced pace - hardly a good test, or a fair one.

What wet conditions are a good test for is throttle response and power delivery, and this is where things got interesting.

By the seat of the pants, the Silver Bullet felt like it had an edge in the mid-range, however the dyno charts proved otherwise.

The absence of the dip in the 5000-7000rpm range probably played a part in this, as the Silver Bullet's dyno curve is pretty linear in that area.

The power difference between the two can be put down to the fact that the standard SP-1 fuel-injection system, as on the silver bike, runs a little rich.

Leaning off the air/fuel ratio would definitely improve power - as was the case with the PC3R on the AMCN bike - and a marginal improvement is gained in the 'real world' thanks to air being forced into the airbox above certain speeds.

That said, the slow Honda Corner (Turn Four) and MG (Turn 10) were particularly slippery, and I was quite ginger on the throttle exiting both turns - but at these low engine speeds, the Silver Bullet felt the smoothest when I cracked the throttle open.

On the faster corners such as 11 and 12, though, the Red Baron's throttle response was smooth as silk, and the engine was noticeably snappier up top.

SOGGY SESSIONS
In fact I must admit I was pretty impressed how easy it was to ride both SP-1s in those atrocious conditions - a thought I pondered as the tornado-like winds forced fat raindrops inside my visor.

I didn't get a scare once, and this I put down to the improved user-friendliness of the modded SP-1s, and the Pirelli tyres.

The MTR21s had already impressed me in the dry at Broadford recently, and did the same at Phillip Island in the wet. Once again the feedback was brilliant, and the grip far in excess of what I expected from a road-focussed tyre.

As for which bike I prefer, well that's a hard one. The Silver Bullet wins the aesthetics stakes in my book, and sounds better too, but that's just my humble opinion.

However, my hoon instincts lean me towards the more powerful and nimble Red Baron - but with similar suspension mods the Silver Bullet would close the already small gap.

The object of both bikes, of course, was to improve on the standard fare, and to that end they have achieved their mandates.

It is possible in this day and age of technically-advanced and well-developed bikes to get a bit lost trying to improve on factory-supplied hardware, though the Silver Bullet and Red Baron have succeeded admirably.

Unfortunately, we now have to really give back the SP-1. The ride's over. Maybe if I plead with Honda just once more. I require perfect weather this time though...