Q: Hi there and thanks for the ‘free’ technical advice. I really enjoy reading your technical column.

I have a 2007 Triumph Bonneville 865cc model. I recently decided to take on a track-day at Kyalami for the first time in 20-years, so I was a little nervous to say the least. I managed to take off 10- seconds from my lap time during the day but it made my ‘bouncing Bonnie’ become a ‘ bucking Bonnie’. So I wound up the rear pre-load as far as it would go, which improved things with less up and down rear wheel movement and less foot peg scrapes.

I’d like to smooth out the bone-jarring jolts on the road and potholes and carry the missus occasionally. We have a combined weight close to 200kg.

I’ve already fitted a free-flow exhaust, removed the emission intake garbage, removed the baffles from the air-box, re-jetted, new sintered brake pads and added more fork oil.

So my question is, would it be better to get someone local to upgrade the suspension or should I import things like shocks and progressive fork springs? I’ve been checking out Norman Hyde products from the UK and came away with a R10,000 wish list, ouch!

Richard Sprowson

A: Anything imported from overseas can become horrendously expensive due to our ridiculous import charges. Might pay to go on holiday there and fill your suitcase, if you know what I mean?

But we have suspension specialists in South Africa that should be able to help.

I could definitely help if you can send or bring me your shocks. I’m sure I can match them up with something far superior to the original items. Don’t forget your bike is designed to be a cool cruiser and the suspension is unfortunately only designed for that purpose. So you’re correct in that the front and rear units certainly have to be addressed. But let’s see what we can do to save you money?

So all I need is a rear shock to measure the length and see the mounting points, and then we can tune to your required weight demands with spring dimension.

I can also inspect the forks and possibly install new and better springs, and use some reputed new fork oil. I’ll also get an ‘exploded’ view of the forks from Triumph SA so I can see exactly what’s going on inside.

So please give me a call (011 792 5795) and possibly bring the bike to my workshop? I’ll make a plan to make things better, how’s that?

Q: I’ve recently bought a Bajaj Pulsar UG3. After owning the bike for only a few days the starter relay began to make a buzzing sound, when I pressed the starter button, and then all the electrics would go dead.

But when I pulled in the clutch everything seemed to come right, so I removed the switch at the clutch lever and it seemed to sort out the problem.

Lately though the electric starter doesn’t work at all and the hooters (two of them), stay on all the time, so I had to disconnect them as well.

The battery charging voltage is only 10-11 volts, which seems to be a bit low. And the LCD instrument back light is also intermittently low.

Do you have any ideas on what these electrical problems could be because the bike is mechanically fine?

Idreesabed

A:  First of all the charging voltage, if you’ve checked correctly, is indeed too low. It should be around 14 volts with the bike revving at 3,000rpm. So you might have a battery or charging system fault there.

As far as the other faults (many), it might pay to check out both of the switch clusters each side of the handlebars to see if they’re corroded or perhaps have a ‘pinched’ wire somewhere that could cause a dead short onto the handlebars?

I would also check the multi-plug connector that goes onto the back of the instrument pod to see if that’s corroded or broken and therefore causing problems in that area as well. Did you find the bike in the ocean?

It’s hard to answer these questions because I haven’t seen the condition of the bike but if it were I, I’d disconnect every wire/ connector on the bike, clean them up, and make sure nothing electrical is directly ‘touching’ the frame. Try that?

Q: I’ve just bought myself a Yamaha BWS 100. I’ve been after one for a while now and, at last, I managed to source one from Gumtree. 

According to the previous owner it’s completely standard besides the fitting of a Pincus race exhaust. The guy I bought it from says it’s been ‘jetted’ to suit, but as of yet I don’t know what size.

But my question is about the original Yamaha autolube system. Does this compensate for the bigger jet size or will it have to be adjusted because of more fuel now flowing though the engine? I desperately look forward to your answer because I don’t want any problems with my beautiful new scoot’.

Christopher Nell

A:  I could answer this question but I decided to call Jeremy Pincus (082 645 8969) for you, because he’s without doubt the expert in SA regarding everything to do with two-stroke engines.

Jeremy here. Don’t worry about the autolube system in your ‘new’ BWS. 

Even in my race bikes I just set the pump to the factory settings and I’ve never had any adverse lubrication problems. If you look underneath, next to the pipe, you’ll see a small window where the pump lies. Just make sure the two marks line up when the throttle is closed and you’ll be fine.

My race pipes tend to make the stock engine rev more, up to 2,000 rpm! 

So as engine spins faster more oil is pushed into the engine, because the oil pump turns faster as the engine drives it. Just make sure you use decent autolube oil though, like Motul for example.

Any problems give me a call on the number above?

Q: I was wondering if you guys could help me with something? I happen to own a 2005 Aprilia Caponord and recently decided to fit a top-box because I’ve always just strapped things to the original rack. Not such a good idea when it rains though.

But when I took the bike out after installing it began to weave when I passed 160km/h. It’s not too bad but it can become a little unnerving at times, especially when the wind gets strong.

So why would just fitting a mere top-box have such a bad effect on the handling of the bike and there seems to be no mention in handbook telling me not to do so? Thanks for your time.

Francois Berni

A: It’s all down to nothing more than changing the aerodynamics of your bike. I’m sure there’s nothing wrong with bike itself.

You see normally and before the top-box fitment the air will swirl around your body and be swept away. But now it will be disturbed by the top-box and perhaps cause a form of vortex behind you, which has obviously upset the bike. Have you tried it with a passenger because I’m convinced it will be better, because the ‘hole’ will now be filled?

All bikes are tested in a wind tunnel and not with a top-box unless included with the original bike. There are simply too many top-boxes out there to test them all on each bike at high speeds. However most manufacturers, including Aprilia, will tell you not too exceed stipulated speeds when accessories, like this, are fitted. So you just might want to read through your manual once again?