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  Honda FMX. Tet goes back to the Supermoto way of biking.

Well, not in the true essence of Supermoto I should add, which is off road bikes with road wheels and tyres, this one is built for the road and even though it is considered dual purpose by the manufacturer, it isn't by me!!

Since selling my WR400 a couple of years ago, I have missed it no end. In fact I have missed that bike more than any other I had owned, but I didn't miss the saddle and the small fuel tank. So, I needed something that would go further and be more comfortable, but still be immense fun on the roads in and around the area I live.

A couple of years ago Yamaha brought out the XTX660, which looked just the job, but on closer inspection it let itself down in terms of not being finished properly. The wheels had galvanised spokes, the hubs had no coating on them at all and several other parts were not quite what I would require for an all year round hack. After all, that is what I was wanted. I could have gone for a KTM Duke, but they are pricey. I did road test a KTM Super Duke, but that is a sports bike without a fairing and clip ons, so there is no point, but very sweet engine. But it does cost only £500 less than my Blade, so not at all what I was after. It had to be cheap, but good. By the way, I still have the Blade too, so the Supermoto was a 2nd bike.

In 2005 Honda brought out the FMX650. This featured the old (very old) Dominator/SLR 650 engine that has been in many a single cylinder Honda over the years. I would have thought the XR650 lump would have been better, but Honda didn't. The Honda was about £500 cheaper than the Yamaha and also looked to have some of that Honda quality about it too with stainless spokes, finished hubs, Renthal bars and generally more painted bits that should stand up to some of the English winter, so I bought one in November 2005. It is down on power a bit compared to the XTX, but it does look a tidier bike, weighs a few kilos less, but is built to a budget.

The rear shock is very exposed and I am having trouble finding a rear hugger for it. The shock only has spring preload adjustment, but the forks have no adjustment at all. However, they are long and thick enough and seem to be fine, giving a firmer ride than one would expect. It even comes with first generation Pirelli Dragons - God I remember them on my '92 Blade and they still make them now! Bloody cheap to replace too, about £60 for a rear and £40 for a front, not bad at all.

So far through the winter I have had a right laugh on this bike. Honda call it a Funmoto and the PR stuff is all about commuting etc. but it is no good as a commuter as there is no where to put anything unless you have a ruck sack, and riding it around town would be a waste. But it is fun - this bike loves twisty back roads .. wet or dry, it matters not. The bike has been covered in grime and general crap from the filthy roads, but it seems to clean up well. When I bought it, I also bought a bottle of stuff called 'Protect and Ride', which is for spraying all over your pride and joy and then riding it through the winter. This stuff seems to work and doesn't wash off, you need white spirit to get it off (I hope), but it means keeping some of the bikes nice shiny bits nice and shiny.

There is potential…………

When recently reading a small article on the FMX in Supermoto magazine they suggested Honda have put that engine in for a reason, it's very tuneable. As it is an old engine it has also been starved of breathe to ensure it gets through Millennium emissions regulations, so it may not be too difficult to get some more ponies out of her by easing the breathing, it will just cost a few bob for pipes and filters. The inevitable big single exhaust noise has been tamed with a tiny tailcan outlet so that'll have to go too.

Thus first on the list is a full Arrow Race system with decent headers and a less restrictive pipe. The exhaust headers on the standard exhaust are so small it's no wonder she runs out of puff quick, it just can't the air in and gases out quick enough, so initial grunt is good but short lived. I opted for the full exhaust system as opposed to just a couple of end cans as I feel the bigger headers are essential. I reckon this should release a few horses in itself. Once Dynojet and K&N start making some bits too, they should help get a bit more out of it and that's all I will do - the internals can stay as they are.

  Large bore

Right, today I fitted the full Arrow system to the FMX. You end up with quite a few bits you don't actually need in terms of nuts, washers and spacers. The spacers in particular seem to only be needed if you just fit the end cans to OE headers. The reason for this being that the headers that Honda fit are much, much smaller than the Arrow headers, (which I must say are a work of art). The new headers are much shorter than the Honda ones and are better tapered .. you can easily fit the end of the Honda header INSIDE the end of the Arrow header. As suspected, the OE equipment is for emissions, therefore extremely restrictive.

The entire system fits like a glove and the old one was off and the new one on in about 90 minutes and this seemed like I was taking my time. The weight saving was the biggest surprise - there is a total weight saving of 5.65 kilos, so now the all up dry weight should be around 162kgs, which is far more favourable.

The bhp increase as per the Arrow figures is 2.5 PS, but I suspect this is with baffles fitted - the baffles each have a small orange warning label on them stating that removal will increase performance, but the system then falls out side of homologation regulations. Oh dear, what dilemma. Shall I be running it without baffles? I shall just have to start wearing earplugs again.

Sounds fantastic, bloody loud and the back pressure is immense - it frightened the life out of my 10 year old son!!

  Needles

With the Arrow system fitted the bike seems to breath a lot better, the gases now get out, but the problem is that the gases also need to get in. One problem I encountered when I first got the FXM was that Dynojet do not make a carb kit and K&N do not make an air filter for it either, at least not yet and unless some one can advise me who does, I’ve drawn a blank so far. However, back to the issue of getting the gases in….the bike was running a bit weak with the new exhaust as expected, so I thought let’s do one thing at a time and see how we get on.

First, I removed the carb slide to take a look at the needle and see if I could raise it a bit. The carb was simple enough to remove and the slide easy enough to get at, much of the work being carried out with the cables attached and the carb, still ‘sort of’ on the bike. Since the days I had my VTR I still had some main jet needle spacers so I could raise the slide a bit. This allowed the bike to run a bit richer on tickover and helped when riding it, but it still wasn’t responding quite as I wanted, but it was an improvement.

Rode the bike about for a while and when I found some time took the carb out again to take a look at what size main jet Honda had fitted. This turned out to a 168, so I dug out my box of jets to see what I had left over from the VTR days. The majority of jets I found were actually Dynojet mains, but I didn’t want to fit these as I don’t have a Dynojet needle and needle profile is all important, so I’m told. In the end I found the original mains from the VTR being a 175 and a 178, so I opted for the 175 to start with.

Once all back together, I started her up and immediately you could feel the difference in the throttle response. Now the benefits of the full exhaust are being felt with the bottom end being much, much stronger - pulls very sweetly indeed and now lives up to it’s name of ‘Funmoto’ even more. I may go for the 178 main in time, but if I go much further than that, I then come into the realms of needing to flow more air and without a high flow filter this will not be easy. But so far so good, the bike is excellent and producing more power than it did stock.

Noisy pipes save lives!! That is a very true statement, but what I don’t necessarily need are people living a mile away hearing me start the FMX up, so I have left the baffles in place. What I did do was start to drill some more holes in the baffle to make a bit more noise, so far I have drilled 2 x 5mm holes in the blanked off end of each of the baffles, this allows a little more flow from the exhaust and also allows a nicer sound too, not quite illegal, but rather pleasant, there’s plenty more to drill yet too.

One other addition is a set of FMX brush guards that Honda market themselves and made by Acerbis, these add to the overall aesthetics of the bike and do actually keep the cold winds of Winter off your fingers and knuckles just a bit more.