XRV 750 Africa Twin

Africa Twin

 Nowadays I ride an Africa Twin.

In the early 1990s Honda Africa Twin and Yamaha Super Tenere dominated the market of big, heavy and powerful enduros. Today a bike with 60 horses is no longer called powerful, although 205 dry kilograms is today just as big and heavy as before. But compared to the likes of Varadero, Kawasaki/Suzuki KLV or Capo Nord AT stands out as a nimble bike that does not mind at all being rushed through small forest roads. Of course "real" enduros that are almost 100 kgs lighter make you eat the dust in the rough places. However AT also takes you comfortably the necessary 500 km or so to get to your favourite gravel strip, as proven on the 2005 KKKKmeeting.

My bike is a 1997 vintage RD07. As I bought it the odometer showed 68300 km.

Driving experiences

After the Tengai my AT feels powerful. Overtaking is easy at highway speeds even with a passenger on board, without need to shift gears back and forth. On crooked roads the AT is very agile and feels light to handle as long as you are travelling at some speed. Advancing at a brisk pace on gravel roads is a true pleasure: there is enough power to control the bike with the throttle, and the bike feels stable and secure. But if you need to put your foot on the ground for support, or if you have stopped and try to push the bike, you are reminded of the w-e-i-g-h-t. This is the deceptive side of a big enduro: as long as you are moving and you have not lost traction completely, everything is nice and easy but if surprises happen, the bike starts to have a will of its own.

The useful rpm range starts at 3000. If you drive actively you tend to stay near 5000 rpm. The fuel economy is reasonably good: about 5.5 l/100 km in mixed use. The standard mixture setting in the AT is very lean and at least my bike suffered from irregular running. The problems disappeared after main jet replacement.

Modifications

taller seat
The seating geometry is OK for a tall driver. A previous owner had lowered the seat by ca 5 cm but this felt a bit odd to me (189 cm). I padded the seat back to standard dimensions. I used harder foam than the original, making the bench noticeably firmer.
lower windshield
The standard windshield protects the driver from wind pressure but it creates noisy turbulence around the helmet. I had tried different windshields with the Tengai and learned that if you want to have a silent ride you must either have a very large shield or none at all. A medium sized shield in fact accelerates the airstream at head level and creates a massive turbulence right there. It is much better to have your head in an undisturbed stream. At 68600 km I replaced the standard windshield by a stub cut from polypropylene. The noise went down dramatically but at high speeds (over 120) the wind pressure starts to strain your neck.

12 V outlet
The GPS navigator is a battery hog. I built a simple frame from aluminum sheet and used a 12 V socket from Biltema. The current comes from the instrument light circuit, sufficient for GPS or a mobile phone.

crash bars
During the winter I installed crashbars from MO-TECH. The first delivery from Detlev Louis contained something quite different than crashbars, but on the second try I got te right stuff with very polite apologies. To my delight they fit quite well.
The only glitch is that the upper mounting plate touches the hydraulic pipe of the front brake, when the front fork is in the end position (for example if you put the steering lock on). You would want to grind a few mm off the corner of the plate.

chain lubrication
On dirty or dusty roads the chain will require lubrication about every time you stop for gasoline. I think these bikes should have a fully enclosed chain as standard. In fact I experimented with a chain cover but found that it would take rather big modifications to make room for the enclosure. I gave up for the time being and built a simple manual chain lubrication device from an oil can. I cut the nozzle in half and put a piece of plastic pipe in the middle. I drilled a hole in the plastic chain guide that goes along the lower front end of the swing arm, and pulled the nozzle through the hole. Then I filed the tip of the nozzle so that it was level with the surface of the chain guide. Two or three squeezes from the can lever and here we go.

The lubrication worked beyond all expectations. During the first 20 km or so half a can of oil dripped to the chain and from there to all possible places where you don't want it. At home as I watched the oil spot grow under my bike I realized what had happened. The far end of the oil pipe was lower than the oil can. Once the pipe had filled with oil gravitation would keep it flowing on its own without anyone pumping at the lever. I added a T junction at the middle of the pipe, with a piece of pipe going straight up. The open-ended pipe balances the pressure and stops the oil from being sucked from the can.

Maintenance

70830 km
New rear tyre Dunlop Trailmax. Front tyre Michelin Anakee 50% worn at the time.

75039 km
At the beginning of the 2006 season I adjusted the valves, changed engine oil and filter, brake fluid, and half of the spark plugs. AT has two spark plugs per cylinder, and lacking the special key I could not replace them all. As the replaced plugs looked quite good I left the remaining plugs for next winter.
The valve clearances were too small, bordering on dangerous. Inlet valve clearances were increased from 0,04..0,06 mm to 0,12..0,15 mm and exhaust valves from 0,06..0,08 mm to 0,15..0,20 mm.

75340 km
I replaced the fuel pump. The old pump still worked but the circuit breaker points were worn and I thought I better replace the pump now and don't wait for it to fail on the road, as seems to be the case with many ATs. The new pump Biltema 523228 (actually made by Facet) turned out to be the wrong choice. It worked OK but obviously the pressure was just a bit too high, because the bike would now and then drip gasoline from the carburetor overflow pipe at idling. After a couple of hundred km and a week of pondering I again replaced the pump, now for a Pierburg model 7.21440.51.0. The pump fit the original rubber mount after winding some duct tape arond it. The standard fuel hoses fit both replacement pumps. If you want you could cut away some excessive length. The pressure seemed to be OK, no gasoline spots anymore.

75810 km
Since the beginning the bike had been stuttering at even speed around 80-100 km/h. The problem disappeared when I replaced the stock 115 size main jets by 120 sized jets. I considered adjusting the needle valves but this turned out inpractical. The needles cannot be adjusted and adding shims to raise the needle will not work, since it would prevent the valve from opening fully.

78866 km
New front and rear tyres: Continental TKC80. Experiences: A compromise tyre. In spite of its rough looks it does a decent job on paved surface and you can lean deep in curves without a wobbly feeling. On dirt roads the TKC is no match to "real" knobbed tyres with a more open profile. The rear wheel is easy to control and slides gradually.

80645 km
New chain and sprockets. The old chain had started to stretch rapidly and even worse, the retaining clip of the master chain link had somehow eaten its slot wider and threatened to jump off anytime. I decided not to take any risks but put a riveted link in the new chain. I have riveted one chain before using two heavy hammers and a punch. This time I bought a proper chain riveting tool. They cost a fortune but I found a reasonably priced one at Louis

82508 km
End of season. I changed the engine oil and replaced the oil filter and air filter. I have been using standard 10W-40 mineral oil in my bikes. It would be possible to spend a lot more money in fancy engine oils, but I cannot see how it would pay itself back in a low powered engine like this. At least synthetic oils were not available at the time the engine was on the drawing board at Honda.


I checked if the valve clearances had changed during the year. The answer was a reassuring "No" but it took a while to get to it. Valve adjustment is not easy with this bike. The front cylinder head is surrounded by the frame and space between is taken by the carburetor assembly, ignition coil, radiator, and miscellaneous ducts, wires and cables. They block the access to the valve adjustment caps and even if you managed to open them you would not be able to do anything with the valves. I detached the ignition coil and loosened the radiator fixture screws so that I could lift the entire cylinder head cover up and expose the valves one side at a time.
The rear cylinder is much easier. You can easily remove the whole cylinder head cover and have good access to the valves.
The photo also shows, how deep the other spark plug lies. It is seated at the bottom of a passage whose mouth (but not the spark plug itself) is seen between the exhaust valve and the cam chain.

The mounting of the side bags cannot quite handle its job. The Givi bags snap to a C shaped aluminum frame, which is connected from its upper wing to the bike's rear subframe. The lower wing is only fastened via a rod going forward and down to the connecting point of the passenger footpegs. There is nothing to prevent the bag mounts from twisting in bumps. The forward mounting rod bends back and forth and develops cracks over time. The right-hand rod finally broke and had to be welded.

85044 km
New rear tyre Metzeler Karoo (T). TKC80 lasted almost 7000 km. The new tyre resembles TKC80 both visually and in terms of handling. The old TKC80 front tyre has groove left but it is worn in a peculiar way. The single middle knobs stand out high but the pair of middle knobs in every second row are heavily worn and slanted.

85250 km
Rear brake pads replaced. The drive chain showed first signs of wear and needed tensioning after 5000 km. I thought the sprocket might be worn more than the other parts and it could be eating the chain. I don't know it the theory makes sense. Anyway, it is not expensive and as a precaution I replaced the front sprocket. The old one was somewhat worn but still in acceptable shape.

Mika Jahkola

+358 400 623 734