VFR800 Regulator Rectifier Fail

andrew Maintenance, VFR Leave a Comment

I’ve read about it, I’ve seen it many times on numerous internet forums, but I never thought it would happen to me. When I bought my bike, I checked to see whether the original had been replaced, and saw the words Tourmax on the top of the unit, and assumed this was an aftermarket replacement. All good. Then I started to notice the battery going flat.

Initially I assumed his was down to the cold weather, and the fact that I was using my heated gear, which draws from the battery. So I stopped using the heated gear, the battery still would up flat. One time leaving work I had to bump start the bike, and othe other time leaving Gloucester Services after stopping for some emergency Mont d’Or (they do have some rather excellent cheeses in Gloucester services).

Out came the Haynes Manual, electrics section, charging, and a level 1 diagnostic was run. It goes a little like this, check the battery is charging properly which means over 14v at 5000rpm. Mine was reading 13.6V. If not over 14v then check the wiring to the R/R.

Next, the alternator feed was checked for resistance: 0.6 Ohms between each of the three coils, and no continuity to earth, that’s fine. Next the other connector is checked (on the loom side not the R/R), all good there. The book says check the R/R by swapping it out. Great.

£101 later and David Silver spares ship out an OEM unit which I’m installing tonight. It looks remarkably similar to the outgoing one, albeit with an aluminium plate to which it is mounted, presumably as some kind of heat sink. I’ll let you know how it goes. When I plug the old connectors back in, I’ll be dosing them in ACF-50 just for good measure and to keep those connectors from seizing up in the future. This is one thing I don’t want to be replacing. Bummer.

Just swapped out the R/R, checked the battery, it’s reading 14.4v, so it was the regulator / rectifier. We’re back in business. How does it feel? Like my bike has had a heart transplant. The bike fires up immediately whereas before it would turn over and over before finally firing into life. It feels more sprightly too. I obviously hadn’t noticed the gradual demise of the charging system, and just thought the bike had a worn alternator, it turns out it was the regulator. Who knew? Most VFR owners, it seems.

HOW2: VFR800 Valve Clearance Check

andrew Maintenance, Tutorials, VFR 1 Comment


Ok, I admit, it’s been a while. It’s now August 2017, the VFR is showing 74k on the clock, and I finally found the time to get round to checking the valves. I wasn’t overly concerned to be checking 32k after the last. As I have said before, if your engine still pulls like a train, chances are you don’t need to check the valves. But in the interest of good motorcycle husbandry, and being comfortable thrashing the hell out of the VFR’s sonorous V4, and lets be honest, bouncing off the limiter is where every good V4 engine should be, it’s worth checking the valves. If you follow the instructions below, within a full morning, 5 hours or so you should have the job done. You can spend the afternoon balancing the starter valves and lubricating the throttle cables.

So here are the steps (with photos) to checking your valve clearances. Before starting make sure you have the following to hand:

  • At least a day of uninterrupted time, ideally a weekend to allow for cock ups, lack of the right tools etc
  • A dry space to work
  • nitrile rubber gloves – I like the purple ones 😉



you’ll need some of these to check your clearances covering 0.1 -0.4mm in 0.02mm increments usually: 0.13, 0.15, 0.18, 0.2, 0.23, 0.25, 0.28, 0.3, 0.33, 0.35, 0.38, 0.4

Making sure engine is cold overnight before starting, take of both side fairings:

valve clearance

Remove seat, then remove the seat, raise and prop the fuel tank

valve clearance

Remove screws and remove airbox cover and air filter

valve clearance

valve clearance

Unscrew inlet nozzles for throttle butterflies holding down airbox base. Remove airbox base noting where all connectors and hoses connect: There are two PAIR hoses, one at the front and one at the back (see above). The rear cylinder HT coil leads (see above), the grey connector and vacuum hose on the rear right (MAP sensor) one hose for each starter valve (labelled 1,2,3,4 – two on each side of the airbox) Lift the base slightly and disconnect a white connector (intake air temperature sensor) and two hoses underneath the airbox. Disconnect the connector on the front right of the airbox, this is the variable intake solenoid valve. Disconnect the vacuum hose #12 linking the solenoid to the one way valve, and the hose #10 from the vacuum reservoir mounted on the front of the airbox. Finally remove the pair hose from the front of the airbox. That should be the lot. Remember to plug them all back in when you reinstall. Heres the exploded view form the Honda Service Guide.


Remove bolts from oil cooler and drop it forward. Behind you can see the pair valve and hose which attaches to the airbox and HT leads for each cylinder.

valve clearance

Loosen bottom support brackets and side mounting bolts holding side mounted radiators and drop them down to gain better access to the front cylinder head

valve clearance

valve clearanceRemove pair hose and HT leads. Loosen four boltsholding down cylinder heads and remove

.valve clearance

valve clearance

Remove crankshaft inspection cover plate

valve clearance

valve clearance

Using a 17mm socket, rotate the crankshaft clockwise until marks line up as show above for cylinder 1 (rear left hand side when facing forwards). You will feel the compression of the cylinders as you rotate. You want to get each cylinder at Top Dead Centre – you can tell if you have achieved this by looking at the gear driven cams to see where the lines inscribed into them are located. See image below.   If the lines are not as shown, rotate the crank another 360 degrees and check again. Measure both inlet and exhaust valves using your feeler gauges. Mark on the sheet. Continue with cylinder 3, then 2 then 4 as detailed below.

  • Inlet clearance 0.16mm (+/- 0.03mm) : between 0.13mm and 0.19mm is fine
  • Exhaust clearance 0.3 (+/- 0.03mm): between 0.27mm and 0.33mm inclusive is in spec

valve clearance

valve clearance

Gear driven cams aligned for cylinder 1 check


You should be aiming for a firm sliding fit. Some resistance to the gauge but still sliding freely.

If all valves are within spec, you can reassemble, if not you need to take the cams out and measure shims and swap them out for different sized ones. This is a more involved process, but not impossible.

If you have never checked your clearances, I recommend you check them at least once. Allow a week off the road and a weekend plus evenings to do the job. If you need shims speak with your local Honda dealer or get David Silver Spares (UK) or David Silver in the US  to sort you out. You could also buy a hot-shims kit from the US via eBay as I did, and never have to worry about getting shims in the future. The VFR uses 7.48mm shims, like the majority of Jap sportsbikes.

When reassembling, make sure all gaskets are in place and correctly seated including those in the cylinder heads. There is an edge rubber gasket and a gasket for each spark plug (diamond shaped). There are two locating dowels with a rubber o-ring (visible in the photos above) and each of the four cover holding down bolts has a gasket too.


When reassembling it is also worth lubricating the throttle cables, adjusting the idle speed and balancing the starter valves. I will explain how to do this in due course.

If you want a copy of the VFR service manual, drop me a line.

Original Post

So the VFR’s clock has just ticked over 58k, and the last clearance check was at 42k, that makes 16k miles in my book, so time for anther clearance check on the old V-Four.

I’ll get around to the task soon enough, and when I do, I’ll show you how to check (and adjust if necessary) your valves. VFR is a great bike, but people can be put off by things like valve clearance adjustments. They’re not that hard to do, and with the right tools, a dry space and a bit of patience, you can do it yourself with ease.

First, I want to share with you the excel spreadsheet I developed to perform my valve clearance checks, this makes it easier than doing the calcs by hand, although I would recommend you check and double check the calculations, and don’t rely on the spreadsheet completely. Click on the link below.

Enter your clearances in the boxes, if they are out of spec you will need to take out the cam shafts and measure the shims and type that in the shin box. The spreadsheet will do the maths for you. Essentially if your clearances are too tight you need a smaller shim. If your clearances are too big, you need a bigger shim.

I’ll go into more detail as we go along, but for now, here’s the spreadsheet.

VFR Valve Clearance Check Calculator

VFR800 Valve Clearance Check

HOW2: Change your Own Tyres

andrew Maintenance, Tutorials Leave a Comment

I just threw a new set of Pirelli Angel GT tyres on the VFR yesterday. It took, all in, about 2 hours to do. That’s a record for me. Having done the job before, I knew what was required, I also knew that it’s more about technique than brute force. But we learn in life from doing, busting a gut, and realising there is an easier way.

My tools? A Powerpack / Compressor, three tyre levers, three rim protectors and a Valve Core Tool. The other ‘specialist tools’ were a bottle of Muc-Off Bike Cleaner (as lubricant) a plank of wood and another small piece of wood I found lying about the garage. Oh, and a brick wall. I have a wheel balancer, but the wheels were fine.

The various bits of wood and the brick wall were required for the hardest task, breaking the beads of the tyres, the rest was pretty easy with generous application of lubricant and the correct technique, which means working steadily round with three levers and protectors, and making sure the bead nearest you into the middle portion of the wheel.

If you’re in the market for rim guards I use those cream coloured ones with a bit of string on. They are sold by laser, sealed and various other brands and you can get them on eBay and Amazon. The tyre levers I use are Sealey Deluxe tyre levers. I use three which is necessary for the job. Two wouldn’t be enough. One holds the position, and two are used to alternately advance the tyre over the rim.


you’ll need three of these…..


and three of these…..

Technique Technique Technique….

The key to the whole process, including the initial bead breaking, is plenty of lube coupled with good technique. You can’t get enough lubrication when you’re man-handling industrial rubber. Remember these tyres stay in place on the wheel by their own friction. That’s a lot of friction force, so if you want to get around it , and if you don’t want to sweat a lot, you’re going to need some water based spray to slip it all up. I used Muc-Off Bike Cleaner as I have a bottle in the garage and it dries non-greasy, but window cleaner works too. Don’t use oil, for obvious reasons.

  1. The first task is to break the bead. First you need to let the air out of the tyre. Remove the valve core with a Valve Core Tool, and using your plank and block and a wall to lever it against, push down the tyre edge until it pops over the bead. Spray on lubricant liberally to aid the process. Once it is broken, push the bead down all the way around. Flip the wheel over and repeat the exercise on the other side. If your wheel in question has brake disc(s) present, prop the rim up on a bit of wood to keep it off the floor.
  2. Press down the bit of the tyre nearest you until it is in the middle of the wheel. This is going to make it easier to get the opposite edge of the tyre over the rim. In the middle of the wheel, the diameter is smallest, and this makes the effective wheel diameter shortest at this point, which should make it easier to get the other side off. Every millimetre counts in this situation. Install your rim protectors and start to lever the tyre off the rim, working your way around. Once you have one side off, the other side should come off easily with enough lubrication and a single tyre lever.
  3. With the tyre off, now clean up your wheel, inspecting it for damage. If your valve is in poor condition, replace it with a new one. Now your new tyre is ready to go on. When your’e fitting the tyres, check the direction of the wheel and tyre match. Also, the two red dots should match up with the valve. If the wheel has brake discs present, place the rim on two planks of wood to protect them, keeping discs off the floor during the tyre change.
  4. Getting the tyre on the rim requires just a bit of lubrication and your body weight. Spray up the rim and the tyre edge generously, and push the tyre onto the rim, making sure the dots align with the valve. It should pop straight on. Now push the outer lip of the tyre over the rim nearest you, and kneel on the tyre to get the bead into the centre portion of the wheel, as stated before. This makes the process easier (read: possible).
  5. Work your way around with protectors and tyre levers. Don’t try to take too big bites of the apple, just gradually work around a little at a time, using your protectors and levers until you have the tyre on the wheel.
  6. Spray the bead liberally, reinstall your valve core, and inflate your tyre. You are listening out for two loud pops which is the indication you have seated both beads. If you are leaking air, or your pressure rises above the recommended pressure for the tyre, stop inflating, spray the beads, and if necessary deflate the tyres, and try again. If the pressure is rising, there is no leaks, so it will just need a bit of lubrication to seat the bead properly. Keep your fingers away from seating beads, unless you want to lose them!
  7. If you have a wheel balancer, this is the time to test your wheel. I usually find with the same tyre brand that little additional balancing is required. I bought a tyre balancer from the US from Marc Parnes, but you can get them in the UK too from eBay and Amazon, likewise the weights. You’re aiming for a wheel which you can stop at any point in its rotation, and it stays stopped, if it wants to turn, it is not balanced.
  8. Repeat with other tyre. I don’t normally change both tyres at once, but the VFR is a big bike, and pretty heavy on front tyres, so I did both. By doing it myself, I reckon I saved myself at least £50. That’s a week’s shopping bill. By the way, if you’re interested, I bought my tyres online from Demon Tweeks, the company website is Demon Tweeks, and two Angel GT’s (120/70 and 180/55) cost me £224 including delivery

Photos to follow….


5 Ways Motorbikes are Superior to Cars

andrew Cars, Motorcycles Leave a Comment

Everybody loves a Car vs. Bike ding dong. Here is a top five of my own; areas bikes are superior to cars.

Acceleration – modern performance cars are fire breathing monsters, take the 4WD Nissan GT-R, for example. It’s a formidable machine which can launch 1.7 tonnes of engineering excellence to 60mph as fast as a Superbike. But once it gets going, and the wind starts blowing, there is still nothing that clears off quicker than a motorcycle. Watch this great vid of the GT-R being overtaken by a Ducati at full chat like it was standing still.

The reason? Power to weight ratio. To start, the car has lower gearing to take advantage of the increased traction available through those four driven tyres. As the speeds rise higher however, the bike has an advantage being lighter, and having a better power to weight ratio. As speeds climb over 100mph, the car will always win out, at high speed, the force holding back the motorcycle is drag (wind resistance). Both the car and the bike exhibit drag. The car is pushing more air out of the way, but it also has more power and more torque available to do that. On a top speed run, the vehicle with the highest torque to drag ratio wins, this is usually the car.

Cornering – Do you like the feeling of having your head pulled off? Me either. I didn’t ride in a high performance car for many years whilst I was living in London. When I did get a ride in a fast car, I realised how much more enjoyable cornering on a motorcycle is, especially for passengers. As a motorcycle corners, the bike leans over, so the weight, which is pushed to the outside of the corner by centrifugal force is actually acting down through the seat, pushing the rider into the saddle. Cornering fast in a car is very much a flat, sideways affair, and is consequently far less pleasant as you need to prevent your head from being thrown all about the place. There is a reason that Formula 1 drivers have necks like rugby prop forwards……

High Speed Cruising – Weeeeeeee! Going fast is fun, whether you’re on two wheels or four. But there is something about sustained high speed cruising on a motorcycle which is incredibly satisfying. On a bike, the faster you go, the more stable it becomes as the wheels gain inertia and their gyroscopic force increases. At increasingly higher speeds, the steering input has less effect. In a car, the faster you go, the less stable it tends to be, the more your steering input affects the line. High speed cruising on a bike is more relaxing than in a car (once you are out of the wind blast).

Now if you are trying to change direction at high speed, a bike’s stability can make the process hard work. Ask TT riders how many pairs of boots they go through in a typical week wrestling their bikes around the mountain course.

Fuel Economy – high performance cars are great fun, but they don’t half burn through the fuel. Not so with bikes. Modern litre sportsbikes bikes can achieve 50mpg at a steady 90mph. Your car? Not so much. A smaller footprint to the wind blast means a bike is pushing less air out of the way at speed, and as the drag increases in proportion to the square of the speed, cars have a lot more air to push out of the way to keep up that speed. They have the power to do it mind, but that 4.2 litre engine is going to burn through the fuel PDQ. If you feel guilty about destroying the planet with your high speed driving, get a bike and save the planet one litre of fuel at a time.

Less Massive – there is something wonderful about propelling a light vehicle forward. ‘Taking off’ on board a modern Sportsbike is a bit like being fired out of a canon, or perhaps fired off the deck of an aircraft carrier. It can be fun to do the same in a car, but you can sense the car’s greater inertia, which makes it feel heavy. There is a greater force to overcome the inertia. Under (F=ma), if the mass of a car is 10 times greater than a bike, and the accelerating force is 10 times greater, the vehicle will have the same acceleration (10F=10ma), cancel out the 10’s. A jet plane may accelerate as quickly at a motorcycle, but it feels big and heavy and substantial. A motorcycle feels light and flexible and easily thrust forward. If you like feeling light and flexible and free, accelerating on a motorcycle is where it is at.

Lighter mass to accelerate also means less wear and tear on the planet, less fuel burned, less tyres consumed, less brake dust created, and less oxygen consumed. Sold! To the man with the green tank top.

Biker Essentials #2 : Top Box

andrew Gear Review Leave a Comment

Motorcycles are wonderful things. In a network of roads clogged up with cars, (largely SUV’s carrying one person), riding a motorcycle in the tens is a similar experience that car drivers enjoyed back in the 1960s. The freedom to travel wherever we want, in a timeframe which is virtually guaranteed to within 10 minutes’ accuracy. Alas it is not so with car drivers.Read More

GSX-R1000 K5 Review – One Bike to Rule them All

andrew Bike Reviews Leave a Comment

If you approach anyone who has ever ridden a litre sportsbike, and garner their opinions, they will normally tell you that they are too fast for public roads, a ‘handful’, and will make short work of your driving licence.

Switch off the tape recorder however, and they will tell you (probably in a whisper) that they are the most incredible machines, and that they make you feel like a riding god.Read More