Lately I’ve gone through a few headlight bulbs on the XT6 – the low beam (which is permanently on) filament has been blowing, but highbeam is ok. I thought it might be a dodgy reg/rect over-volting things, especially since my battery recently died. On checking, the reg/rect is putting out around 15.5V at idle and at 4k RPM. I also checked the output of the stator by disconnecting the reg/rect and measuring the three phase wires (white) coming into the reg/rect. At idle I was getting around 25VAC, and at 3-4k RPM about 60VAC. I’m not sure about the low voltage output at idle, but 60VAC is a good sign at 3-4k RPM.

Reading various troubleshooting guides, the general consensus is that around 14.5V out of the reg/rect is health, but anything above 15V is a worry. I tested my SRX6 and it sat nicely on 14.5V. The reg/rect it uses looks different so I didn’t want to just swap it to try.

On the suggestion of a mate, I tested DC voltage under heavy electrical load – high beam, brake light and indicator – bingo! 14.0V – 14.5V between 3k and 5k RPM. My previous testing had all been done without the headlight running (blown low beam), meaning the reg/rect had hardly any load at all. My guess is that the low load gave something almost like an open circuit voltage which is a bit higher than ideal. With a decent load (80W or so of lights) it brought the voltage down to the normal level.

Above mate also suggested that the blown lightbulbs could be to do with insufficient vibration dampening of the headlight assembly. I will have to look into improving this and see if it makes a difference.

So, I guess the morals of this story are:

• check reg/rect output voltage under load conditions (highbeam, brake light, indicators etc) at around 5k RPM and see what you get.
• to check coils, rather than measuring resistance, measure open circuit voltage between phases. Resistance will vary depending on power output, whereas voltage range is a functional measure. around 60VAC is good.

Here’s a good electrical troubleshooting guide http://www.offwidth.co.uk/bike/general/electrical_fault_finding.pdf

The dash on the XT has been bodgy ever since i got it – the tacho was damaged, the backlights only worked after a shoddy wiring repair, and the turn signals light doesn’t work. After putting on the motard wheels, the speedo is out too, so I decided it was time to upgrade to a Trail Tech Vapor speedo.

I got the kit from an Australian eBay seller, BigPigMCA, who sells them for AU$170 delivered. Pretty competitive with sellers in the US, and it arrived in around three days, much quicker than getting it from the US.

The first part of the installation was fabricating a mount. I made this mounting plate from 2mm aluminium checkerplate. Pretty rough, but does the job and is fairly hidden. I made the bends by hand and annealed them with a butane blowtorch. Shaping was done freehand with a die grinder and files. Probably the trickiest parts was shaping the top to fit the underside of the headlight cowl, and making the spacers for the mounting bolts – since I don’t have a lathe I had to roughly cut them to length then file them down till they fit.

Mr Dash is happy to accept your Vapor

I pulled the speedo cable off and covered the drive output in tape. I plan on machining up a spacer to replace it at some point in the future. With the tacho cable, i’ve just covered up the cable end. I intend to remove the tacho drive and install a blanking plate. The previous model XT6 (1990-1995) doesn’t have a tacho, and apparently it will fit mine (1996) no issue. If I had a lathe I’d make one myself, but again, sadly I don’t.

Here’s a picture of the tacho drive:

Below is a parts diagram of the cylinder head from a 1990-1995 XT600. Part 24 is the blanking plate I intend to use (so long as it isn’t ridiculously expensive, which there is a fair chance it is)

I wired up the tacho sensor inductively, using five wraps of the positive lead around the spark plug lead, and the negative tied to ground on the chassis.

The speedo pick was a bit of a bodge – I’ll be getting an EBC oversized disc (hopefully!) in a few weeks. Doing a proper mount would have been a pain in the arse, so I figured i’d do a bodgy mount until then.

I didn’t install the temp sensor, as it is unfortunately the wrong size – DR650′s must use a smaller spark plug. I am going to try to find another spot to mount it (oil tank?)

Here’s the finished product:

Still to do:

• Replace speedo drive with spacer
• replace tacho drive with blanking plate
• wire up dash lights (high beam, neutral, turn) using LEDs and mount on dash.
• proper speedo pickup mount once new 320mm disc is installed

A bit of a summary of the current state of things:

• Acerbis 23L plastic tank
• Polaris supermoto front fender
• MEP custom stainless full system
• SMPro rims laced onto stock hubs

Brake upgrades to come….

A man was recently charged with careless driving, after he cut off the acting police minister, while talking on his mobile. Good-o, I say, this is the sort of thing that needs to be enforced.

However, here I sit, four months after being hit by a car performing an illegal u-turn, with probably at least another three months before I go back to work, wondering why it is that a driver who was 100% at fault and caused serious injury, gets a slap on the wrist, in the form of an infringement for performing an illegal u-turn (the same as if you did a dodgy u-turn at a set of traffic lights and didn’t cause an accident). Not even “failing to give way while performing a u-turn”, let alone Dangerous Driving Causing Grievous Bodily Harm, which is the charge that fits.

What this goes to show me is that if you piss off a police officer, you are fucked. But if you do something wrong that is a bit hard to prove (or you do it to a minority group that the police assume are guilty until proven innocent – such as motorcyclists) then you get off scott free.

Is it any wonder that Traffic Police are hated, let alone not respected?

From http://www.abc.net.au/news/stories/2010/02/01/2806594.htm

Nermin Hodzic leaves Brisbane’s Magistrates Court after being fined $500. (ABC News: Jason Rawlins)
A man has appeared in the Brisbane Magistrates Court charged over a traffic incident involving one of Queensland’s most senior police officers.

The court heard Nermin Hodzic, 22, from Calamvale on Brisbane’s southside, was driving north on the Gateway Motorway early last month when he weaved in and out of traffic while talking on a mobile phone.

Hodzic narrowly missed a car driven by Acting Police Commissioner Kathy Rynders who was off duty at the time.

She was forced to break heavily to avoid a collision, which in turn forced motorists behind her to also break hard.

After several attempts she managed to intercept Hodzic and he was charged with careless driving and using a mobile phone whilst driving.

Hodzic was fined $500 and convictions were recorded.

Some pictures of pillion pegs on a 1996 XT600.

1996 XT600 LH pillion peg - closeup

1996 XT600 LH pillion peg - closeup

1996 XT600 LH pillion peg

1996 XT600 LH pillion peg

After a few (regretful) years without an SRX6, I’m back! I picked up this one last week. It’s an 88 model, which has a 17″ front wheel, single 320mm disc, 4 pot caliper, but still has rear twin shocks and is kick start only.

This one’s had some serious work done to it too – wiseco 11:1 high compression piston, race cam, keihin FCR33 flat slide carbs, oval stainless exhaust and WP rear shocks.

Its currently unregistered and off the road (as am I, in a sense…), so I haven’t been able to test ride it yet, but I can’t wait. With all the work it is going to be an absolute rocket!

More pics and details to come soon.

Phil

A new pipe for the XT – nice, but I couldn’t recommend MEP.

Upon motarding the XT6, I discovered I needed a new exhaust, as the stock muffler rubbed against the rear tyre. Great excuse to get a new exhaust! I ended up getting a custom one made at Motorcycle Exhaust Professionals. I opted for a full stainless system, with oversize headers. This ended up costing $800.

Some better pics of their handy work:

While the workmanship seem nice, I must say that I doubt I would buy anything from them again, or recommend them to anyone. I told the guy at the shop that i wanted something not too loud – nothing that is offensive or will get the attention of the police. He was kind of dismissive at the time, but I thought it was just his manner. When I picked up the bike, I discovered that they’d put a straight through, large bore muffler on, with no baffle. His comment was "we thought this sounded nice".

Well fuck, I don’t care what you think, I care about what I asked for.

Riding it home, it was stupidly loud – to the point that it was uncomfortably loud for me. At the shop he was reluctant to fit a baffle, but after insisting he "kindly" gave one to me for only $10. I fitted the baffle when I got home – quietens it down, but it probably goes a bit too far. I’ve chopped a few cms off the end of the inner pipe already, and will experiment further with this to get a decent sound.

So, the bottom line is, yay! i got a new exhaust for the XT! Unless you want a deafening, cop-attracting, neighbor pissing off exhaust, then I would not recommend Motorcycle Exhaust Professionals, unless you want to spend a lot of extra time fucking around to get it sounding decent but not offensive. In hindsight, I probably would have tried Pipemasters – more expensive ($1100 vs $800) but their pipes look nicer and they sounded like they would actually build the system you liked, rather than the one "they thought sounded nice".

If, like me, you ride a motorbike you’ve no doubt heard the many arguments against buying a sportsbike. Things like “the insurance is too much”, “they’re uncomfortable compared to naked bikes”, or “when you drop it it’ll cost heaps to fix”.

While these are undoubtably true, I feel that they’re somewhat superficial, and that there are more substantial, but much less voiced reasons for not getting a sportsbike. I’m talking about road use in australia, so those of you who actually can go over 140kmh without fear of imprisonment, YMMV.

1. Sensation of speed is more important than actual speed. Sportsbikes are fast. No doubt about it. That’s what they are designed for, and they do it well. So well, in fact, that you lose the sensation of speed. If you want to go fast, catch a plane.
2. Acceleration is fun. You want usable acceleration on the street? A naked bike, streetfighter or muscle bike is going to be just as good, or maybe better than a superbike due to tuning for low and mid range power.
3. The street is not the track. Ever tried racing on the street? Can you tell how many 1/10ths of a second faster you are than your mate? I bet it’s not because of your slipper clutch or quick shift. Probably more to do with your willingness to break the speed limit by more than your mate, or your disregard for the gutters, trees and oncoming traffic.
4. If you reach the limits of handling and suspension of a modern naked bike on the street, you’re probably doing something wrong. Learn about throttle control, for a start. If you aren’t doing something wrong, then you’re pushing it so hard that a sportsbike probably won’t extend the limit far enough.
5. Wheelies are fun. Why would you buy a bike with special design features to do things like limit wheelstand under acceleration?
6. The hunched over riding position reduces your field of view, making it harder to look through corners and harder to look ahead for hazard detection and avoidance. Looking through the corners and “you go where you are looking” are some of the fundamentals of riding. With your head down, it takes much more effort to do this than with your head up in a neutral riding position. Hazard detection is a lot harder also, with you more likely to fixate on nearby objects.
7. A bike that isn’t designed for high speed handling and stability, when pushed, will teach you a lot more about riding that a sportsbike will. For example, sportsbikes are set up for a front end weight distribution bias, which increases front traction for cornering. A more neutral bike will have less front end traction, but will be more forgiving (ie front end will push rather than giving way). Shifting your weight to the front will give a noticable improvement.

So, piss off your sportsbike, and get a Super Motard.

Mr Rudd was kind enough to buy me some motard wheels for the XT6. Nice chap he is.

Anyway, I’ve been wanting to do this for years, so I was very excited to finally get it happening. I’ve got spare hubs (one new rear hub, one second hand wheel), which I got motard rims laced onto. I figured this would be easier than cast wheels, since i don’t have the machining skills (or equipment) to make spacers and caliper brackets.

I ended up going through Two Wheel Tyres. Turns out they actually just send them to Ash’s Spoked Wheels. No big deal though, since the two wheel tyre’s price was the same as I got quoted from Ash’s.

I went with a 17×3.5 SMPro rim on the front, and a 17×4.25 SMPro rim on the rear. Both are 36 Hole. I fitted Pilot Road 2CT front (120/70) and rear (150/70), which ride very nicely.

Some issues i encountered were:

• rear tyre rubbing against chainguard – i have a modded FZR250 chainguard, which required spacers and brackets, so this probably won’t be an issue for most.
• rear tyre rubbing against swingarm – some weld seams protruded slightly and rubbed against the sidewall. ground these back to provide extra clearance. installing a few extra links in chain to move wheel back would also probably fix this
• Rear wheel rubs against inside edge of stock muffler. Fitting spacers or hammering muffler in aren’t options (muffler goes inside frame, so too much tension to put more than a few mm of spacers, and muffler is a baffled chamber design, so dints would probably block off chambers causing serious backpressure increases). Good excuse for a replacement full stainless system!
• Due to different front wheel size, the speedo reads approximately 15% higher than actual speed.

At the same time as putting the motard wheels on, I replaced the chain and sprockets as they were completely shagged. Stock gearing is 15/45, and I went with 15/40. My intention was to go 15/43, but the guy at the shop accidently gave me a 40 instead. It is a bit tall, but given that the rear wheel size has changed (130/90, which gives a tyre height of 117mm, vs 150/70, which gives tyre height of 105mm), it is not quite such a large change. It still feels a bit tall, but I’ll give it a chance before going 1 tooth down on the front. I used an RK heavy duty 520 O-ring chain, with a clip type master link. The opinion I got from several mechanics is that clip links these days are very good and never come apart if properly installed. As an added safety, adding a dab of silicon to the clip makes it even more secure.

I also installed a fork brace, which has significantly improved braking power, and stopped fork twist under heavy braking. I got it off a friend – not sure what it is for, but I had to slightly modify it to get it to fit.

Things still to do are get new exhaust system [pic above includes new exhaust - I didn't get around to taking a pic till after!], and a motard front guard. I’m going to go through Motorcycle Exhaust Professionals, and get oversized stainless headers and an oval stainless muffler. They  quoted $790 for the full system, compared with around $1100 from Pipemasters, the other big custom exhaust shop in Brisbane. As far as a motard front guard, I’m going to go either a polaris or acerbis. Morgs’ XT6 motard has a polisport which seems to fit well, but Acerbis seem more common at the local shops, and I’ve heard they are better quality.

Some useful data:

• 17×3.5 front rim is the right size for a 120/70 or 120/60 tyre
• 17×4.25 rear rim is the right size for a 150/70 or 150/60 tyre
• both front and rear rims for the XT600 are 36 hole
• 120/70 and 150/70 rides nicely
• (I’ll include bearing and seal data here soon)

The standard brakes on my 86 SRX6 (jap import) are far from perfect. Based on some info sent to me by my friend Cam, I decided to have a go (with his help!) making some changes to improve things.

On the front, the SRX6 comes standard with a 5/8″ (15.8mm) master cylinder, and twin 10.5″ (267mm) discs on an 18″ wheel, with two 1.5″ (38.18mm) sliding type calipers. Brake lines are a one-into-two rubber hose arrangement standard, but I’ve fitted braided stainless lines. As far as I’m aware, I’m running the standard Yamaha brake pads and Dunlop arrowmax 100-80/18 tyres.

Overall, braking isn’t that good.

The SRX6 pulls up quick enough, but requires quite a bit of lever force – 3-4 fingers. Performance didn’t change much after fitting the braided brake lines. The first stage of modifications involves a Master Cylinder change – but first let’s go into the maths!

(right here I have to thank Cam for doing the research which I’m about to summarise here)

There are a number of factors which affect lever force required, and lever feel. Some of these are: The brake pads, brake line flex, wheel to disc size ratio, and probably the least thought about – Master Cylinder (M/C) size to caliper size (in hydraulic terms) ratio.

The M/C to Caliper size ratio dictates the mechanical advantage you will gain through the hydraulic system. push a cylinder in at the lever end x millimeters, move pistons that push brake pads y millimeters. x is large (relatively – say 10) and y is small (say 1). This ration dictates force. If the ratio is larger, you need less force but more travel (pull the lever in further). If it’s smaller, less travel but more force – 4 finger brakes.

According to Cam’s research, there’s an optimum ratio between the caliper piston area and master cylinder area of 27:1. With a ratio of 27:1, you should have one-finger, sharp brakes. Less than this will require more force, with around 23:1 and lower feeling wooden.

Doing the maths on the SRX6′s stock brakes gives a ration of around 23.5:1, which makes sense, given that the brakes feel a bit wooden. To increase the ratio, I need a smaller master cylinder – 14mm and 15mm are the two options. 15mm gives a ration of around 25.9, whereas 14mm gives a ratio of about 29.7. I decided to give a 14mm master cylinder a go, seems as 1) higher than optimum should mean less force, but more lever travel, which i think should be better than the other way around, and 2) Cam had a spare 14mm M/C lying around I could borrow.

So, with that, I swapped the M/C with the new 14mm unit (with much jiggery pokery and subsequent help from Cam, which I won’t go into, but needless to say it would have been oh so much more difficult without Cam there) and took it for a test ride.

Hooray! brakes are now awesome!

It took me a bit to get used to them, but I’ve now got much better lever feel. One finger is plenty to pull it to a stop under normal conditions. Two fingers will easily lock the front wheel up at 60kmh (tyres aren’t sticky enough for stoppies). Cam adjusted the brake lever to give it a bit more adjustment, which probably helps a lot with lever travel. I think that without the mod that he made (cutting a spring to allow more travel in the adjustment screw, or something) then I’d have more of an issue with lever travel.

So, overall, it made a big difference. Turned wooden brakes into nice, responsive, powerful brakes. If your brakes don’t feel so good, I recommend looking into changing the master cylinder to get an area ratio of around 27:1. It makes a big difference. I fitted braided brake lines a while back, which made almost no difference to me. I’d imagine that maybe now if i went back to the old brake lines I might notice a difference, but without the right hydraulic ratios, I don’t think braided brake lines make much of a difference.

So what’s next? Well, next, I’m going to try a different set of calipers. Someone mentioned that they fitted FZR250 calipers (which are dual pot leading/trailing calipers) to their SRX and got really good results. I’m going to track down a set of these and give them a go. Hopefully I’ll be able to find some specs for them so I can do the math and see what the appropriate M/C size is. The guy who recommended them used the stock 15.8mm M/C, so it’ll be interesting to see what the maths works out as… After that, it’ll be new tyres and new brake pads. Stay tuned!