Advice: Technical Q & A

It can be difficult information to use, though. The seat height measurement, for example, doesn’t take into account the width of the seat at the position where the rider sits. A claimed figure can be quite low (say 700mm), but if the seat is two-foot wide, you still won’t be able to put your feet on the ground because you won’t be able to keep your legs close enough together.

Weight is often given as a ‘dry’ figure, which you might think just means no fuel or oil. For some manufacturers, it also means no brake fluid, clutch fluid, fork oil, rear damper oil and even chain lube. How realistic or comparable can these figures be?

Does ‘claimed power’ always mean the bike engine that produces the most power will be the fastest? No, but it often reads that way. The truth, however, is out there in the real world.

WHAT LIES AHEAD?
I am new to the bike scene, at 47, and will get my open licence in November. I would like to pick your brain. My first bike is a Yamaha Virago 250, which has been a great learner. I am thinking ahead about my next bike – this is, of course, where you come in. I would like a dual purpose tour/trail bike – 95 percent of the time on the bitumen road and something that can go down the odd dirt road, as there are so many where I live. It will also have to be able to carry two, in comfort – well, for the passenger mainly. (I am 185cm and 95kg, and the other half 167cm and 70kg). Could you give me your opinion on a suitable bike?

I was told the 650 V-Strom is plenty big enough to carry two, or do I need at least a 1000 as a lot of other people are saying? I do like the look of the V-Strom but don’t mind the look of the Honda Varadero either. (With the way registrations for bikes is going in NSW, though, size does matter!) There are a couple of bike shops in town with only a small range of road bikes as they mainly carry dirt bikes. If you could point me in the right direction, it would be much appreciated.
Rick Lange, email

GRAFT AND CORRUPTION
I was just wondering if you get an “incentive” from Suzuki for promoting its 650 V-Strom or are they really that good? I have an XJ900 diversion which is a great tourer but not that flash on the gravel. I need to get the photos at Cape Reinga now that it’s tar-sealed so I can match them up with my Bluff pics. The plan is for a dual-sport for next summer. I suspect you’ll recommend a Wee-Strom?
Lloyd Duane, New Zealand

ELSIE RIDES AGAIN
I’m currently restoring an ’85 model Yamaha RZ350LC (for the second time – a mate crashed version one into a Falcon!) It has slip-on mufflers which make a mess of the bike by spraying oil and shit everywhere through poor seals. The carb slides are also worn – they look like a coating has worn off them and they tend to stick. A light clean-up with wet and dry fixed the problem but I think they still need to be replaced.

I seem to be able to get most of what I want in the US but do you know of anywhere I can get parts for the LC in Australia?

While I have your attention, there was someone in a recent issue wondering if he’d flatten his bike’s battery by adding some accessory lights. I’m an auto electrician by trade so you might be interested in my way of testing regulators/rectifiers. First up, get an old rectifier from a car alternator. Attach wires to the three phases and positive and negative of the unit. Disconnect the unit from the bike and plug in your test rectifier to the two or three phase outputs from the stator coil. You then run the positive and negative wires to an external battery via an ammeter and with a voltmeter attached.

This will stop the high output voltage from hurting your bike and will also tell you what your stator coil is capable of outputting exactly. An easy current draw test on the bike will tell you if you are overloading the stator output with any new accessories (larger headlight globes, heated grips etc) fitted.
Tim Waddie, email

Plan B, Tim, is we’ve run your email address and it’s possible there’s a faithful MT reader out there with an RZ350LC tucked up the back of their shed. Buying a whole spare bike would be good as it would provide a host of bits that can be really difficult to get. Best of luck.

BMW POWER TRIP
I’m just writing to tell you of my experience with my current steed – a 2005 BMW K 1200 S. A while ago I fitted a Staintune can and found Grettal (my Beemer is a girl) was hesitant just off idle and on over-run. Originally the intention was to fit two K&N air filters to assist on the breathing side of things but wasn’t sure what effect this might have on leaning out the mixture.

The solution was fitting a Power Commander 111 USB. What a difference! The dyno printout I received shows 156.29hp achieved from 8000rpm up to redline and peak torque (122.67Nm) produced from 7000rpm. 100Nm is available from 4000 to 6000rpm and torque starts to trail off from 9000rpm.

My two questions are how come I needed a Power Commander in the first place? You’d think given the purchase price of the bike that BMW would have something like a Power Commander as standard equipment.

My other question is how dynos work when bikes are fitted with ram-force air intakes. Is air blown in through the intakes while on the dyno or does it not matter due to the air/fuel ratio variability built into the Power Commander module?

John Giordano, email

HANKERING FOR A HARLEY
I’ve owned old British motorcycles for the last 25 years and still do – I can’t get them out of my system. As you can imagine, I’ve gotten pretty good at fixing oil leaks and carrying out general maintenance.

Anyway, I’ve decided to buy a Harley-Davidson as I want a bike that will start with the push of a button and I can ride without having to worry about ringing the missus and getting her to come and pick me up in the ute. Unfortunately, finances won’t allow me to buy a new one so I hope to find a good, low-kilometre used machine and am leaning towards a Road King or a Fat Boy.

I know nothing about Harleys and am trying to gather as much information as I can before I buy.
Can you tell me what is considered “low mileage” for an H-D engine and what sort of miles I could expect to do before a rebuild would be required? Are the twin-cam engines better than the evolution engines?
Neil Nicolao, email

SEAL, DAMN YOU
I’m rebuilding the top end of my Suzuki GS1000S. I’ve never done anything like this before but have been surprised by how (relatively) straightforward the task has been. Reassembly is only weeks away and I’m wondering about the cylinder base gasket, head gasket and tappet-cover gaskets.

The manual doesn’t say anything about it but would you use some kind of liquid gasket as well? One of the reasons the engine is apart is that it was leaking oil from the cylinder base. Any tips for rebuild?
Andy Hoven, Ashfield, NSW

THE LIGHT BRIGADE
I’m having a problem with my Honda VT1100 in that I can’t keep the battery charged. I’ve taken it to a sparky and he can’t find anything wrong. Why would the battery discharge when the bike’s just sitting there? The sparky said it might be a dud battery so I replaced it without an improved result.

I also bought a battery charger to keep it topped up but my wife keeps turning it off (wasting electricity, blah blah). I’ve run over the bike and there don’t seem to be any problems with bulbs, fuses and earths. What could it be?
Crispy, email