Friday, April 4, 2014

What fork oil?

With almost 8000 km on the WR250R and a never-ending winter outside, it was a good time to inspect the fork oil. I had no idea what to expect, given I ride about 50-50 dirt/road and most of the dirt around here has a lot of fine, sticky clay in it. My KLR650 benefited from a fork oil change about every 8000 km after a slightly more aggressively dirt-oriented style of riding. For comparison, the RockShox, Marzocchi, and Fox shocks that I've ridden on my mountain bikes over the years all seemed to benefit from at least an annual fork oil change to remain supply--although the newer Fox suspension I ride now seems impervious to trail grime.

An online search for info on the WR fork oil gave ambiguous results. The shop manual only indicates Yamaha fork oil (no weight), yet the dealer where I bought the WR had no idea what oil that would be and said they use Belray anyway. A couple of litres of 5-weight Honda fork oil, and I was on my way. Yeah, yeah--sacrilege not using Yamalube. But we're talking a Showa fork, same as on a Honda.

The shop manual indicates that each fork, when completely drained, requires 613 mL to refill. Disassembling the fork is a piece of cake (loosen the pinch bolts, slide out the fork assembly, and unscrew the top cap. Don't worry--nothing goes "sproing"). The oil in both sides turned out to be nearly perfectly clean. After recycling one fork's worth of oil, I decided to save the other fork's oil for reuse later if necessary.



The Honda 5 Wt oil was like water compared to the OE oil, which I'd estimate was about a 10-15 Wt. One guy's WR blog said he switched to 5 Wt after getting his forks revalved and tuned--and the result was amazing. Now, eliminating the obvious advantages of revalving, I was curious how just changing the oil weight would feel and figured it was worth a try.  For reference, I weigh 190 lbs and carry about 25 pounds of gear and clothing, and I tighter up the compression/rebound settings to compensate for the lighter oil.

An initial test ride felt pretty good on our winter potholed roads. Front wheel seemed to track a lot better over the little stutter bumps. Obviously this is hardly a scientific test and warmer temps (i.e. at least above 20C versus the 4C during my test) could make a significant difference. The lesson is, it wasn't a disaster; on the contrary, my seat-of-the-pants impression was quite encouraging.

More to report as testing continues.

Update August 25, 2014: Hmmm, not sure I'm liking the 5 wt. May change it for 10, something with a little more damping so my fork doesn't bounce around so much on washboard roads. This should also improve low-speed damping.

WR205R rear rack - update


A shameless attempt to paint my rack with a spray can gave predictably awful results. So it was off to Ottawa Powder Coating for a sand-blasting and proper finish. With new stainless steel bolts for the RotoPax mount, it looks pretty sharp now!





Tubliss inner tube replacement for WR250R

Inner tubes are pain to install, unreliable to repair, and a common point of failure in any off-road riding situation. Fortunately, running tubeless on the WR is possible thanks to the Tubliss system offered by Neutech. While the system may seem a bit daunting to install, it's an ingenious concept that works incredibly well according to many excellent reviews on the web. I recently installed it with my K60 Scouts and thought I'd add my observations to the many others you can find online.


Note that the system is meant for off-road use only. However, I can't see any objective reason why it wouldn't work reliably and safely on a small bike like the WR in a dual-sport (road) application, other than the company probably didn't want to pay for the hassle of DOT certification. It's not like your inner tubes are DOT certified anyway. In my case the appeal of better flat resistance and easier flat repairs won out over the supposed limitations to off-road use. As a bonus, Aviciouscycle just happened to have the generation 2 kits on sale.

Tips

1. Follow the installation instructions from Tubliss. The inner section and the tire have to fit together a certain way to be airtight. If you follow the instructions, it'll work. Just be patient and don't try to cut corners. Some of the negative reviews online don't make much sense: the reviewers probably didn't follow the instructions. 
2. Beware that the K60's are TOUGH tires to install at the best of times. Incorporating the Tubliss adds to the misery. Nevertheless, with practice and the right tools it can be done without too much swearing and sweating. And it's still easier than trying to install inner tubes.
Really clean your rims inside and out, and remove any burrs or rough spots with a bit of emery cloth.
3. Use regular Armor-All as tire lube. It makes mounting the tires a lot easier. 
4. Use tire spoons. You are much less likely to damage the inner (red) Tubliss tire versus using regular irons.
5. The heavy rim clamp and valve of the Tubliss system seriously unbalances the front wheel, as I discovered on my first test ride. It helped to rotate the tire 180 degrees on the rim and use an entire 8 oz bottle of Slime (the Slime instructions recommend using 16 oz per wheel, or two bottles--which I didn't have on hand). The rear seems fine, but I didn't get above about 80 km/hr on my second test ride so more tuning of the balance may be needed for higher speeds. A pressure check before and after the ride showed no pressure drops. The front may still need a few ounces of rim weights, or some more Slime to tune it. 
6. After installing the Tubliss, pump it up to spec and let it sit for a week. A bit of Slime worked its way out of a few places (like around the valve stems), but the pressures of the red inner tire (100 psi) and the main K60 tire (29 or 22 psi in my case) remained bang-on, suggesting no issues with my installation.
7. A good bicycle floor pump with pressure gauge makes inflation easy.

Ride feel

Road feel is noticeably different than with tubes: the tires feel more compliant, somewhat surprising given I was riding in about 4 degrees C when the rubber should be harder. I noticed a similar effect when I went tubeless on my mountain bike. It'll be interesting to try lower pressures off-road when conditions allow it. 

Overall it looks like the Tubliss was a good decision for the WR. Updates to follow. 

Update July 21, 2014: See why I removed the Tubliss system and reverted to tubes.

Thursday, April 3, 2014

WR250R headlight relay

The stock wiring and H4 headlight on the WR result in a feeble light. It's so poor, the first time I rode the bike at dusk I thought there was something wrong with the headlight. Output is nothing like that delivered by the twin 480 lumen LED units I use for nighttime mountain biking. And those units are pretty lame compared to the LED units commonly available now, which typically start at about 800 lumens per head.

Two relatively simple options to improve the WR headlight are to install a headlight relay for the existing bulb, and auxiliary LED lighting to provide more reach and spread than the stock bulb alone can deliver. The headlight relay eliminates lumen-sapping voltage drops caused by the stock wiring (which routes power through the bar switch on rather thin wires), by providing a more direct electrical path through heavier wiring. The existing wiring remains in place and controls relays which send the juice through the parallel heavier wires. As for LEDs, a simple test using my battery-powered mountain bike LED lights shows that the additional 980 lumens mounted on the forks completely drowns out the stock headlight.

So first: what relay solution?

Headlight relay

Many mod sites pointed to the Eastern Beaver wiring products offered by a Canadian who now lives in Japan. Admittedly, I was somewhat reluctant to order a relatively simple wiring kit from that far away--even from a fellow Canadian. However, a closer look at the details suggested his products were pretty good quality, and I know from experience how time-consuming it can be sourcing small quantities of oddball electrical components. So I caved and ordered the headlight kit as well as a switched relay kit and some other items for other mods. Having placed my order on a Tuesday evening, I was blown away that it arrived at my doorstep on the Friday morning! That's some seriously high quality delivery service from halfway around the world!

The quality of the Eastern Beaver wiring kits is indeed absolutely top-notch and likely much better than your OE wiring harness. Although the kits I ordered are not intended for a specific motorbike, the lengths worked out perfect for the WR without leaving any tight spots or excess wire length that was a problem to tuck away.

Where to mount the headlight relays? The solution I devised was to fabricate an aluminum bracket. It tucks inside the headlight fairing above and behind the headlight, right in front of the speedo. This approach offers good mechanical support and protection from the elements, while being easy to access without requiring drilling or modifying the existing wiring (although you do need to cut a zip tie to move an existing bundle of wires).



The pattern is traced from the one I made. The image size should be 8.5" x 11", so if you print it at 100% scale the dimensions should be correct. Cut it out of 1/16" aluminum, drill it, and bend it as shown so it fits behind the headlight fairing using the stock mounting bolts. Note that the two bends at each end need to match the inside profile of the "ears" from the headlight fairing. The Easter Beaver relays and wires simply attach using bolts with nyloc nuts, and zip-ties. It's a tight spot and you'll have to play around with it to tune the fit. I also bent a small  bracket to provide some mechanical support in the middle. Watch that none of the wires rib on any shape edges.  


Here's a view of the bracket behind the relay mount. It's a tight fit to insert the front bolt, so I didn't end up using one there. The bracket alone seems to provide adequate support without the bolt anyway.



Here's the bracket after a cheap and sleazy shot of black enamel. 


Wiring it in

After mounting the relays I fed the wiring back through the frame on the left side, over the cylinder head and inside the frame area above the battery. There I wired it directly to the battery. There's no need to use a key-switched power source since the headlight relays themselves provide an automatic power-off function. Use lots of zip ties to secure wires against vibration, and be sure to leave enough slack for the bars to turn without pinching or pulling on anything that could result in a broken wire.

At the headlight end I opted to remove the existing female connector from the wiring harness (which normally plugs into the bulb) and splice the ground, low-beam, and high-beam wires directly into the Eastern Beaver kit with solder joints and adhesive heat-shrink tubing for weatherproofing. The relay wiring kit includes a new connector for the bulb (switched by the relays). Note that you can't just match colors - the high/low beam colors on the kit are reversed from those on the OE wiring.

So how it works is the existing switchgear just activates either the low beam or high beam relay, which in turn sends power to the bulb directly from the battery. The result is a noticeably brighter headlight.

The whole shebang adds one more point of failure for the headlights via the additional relays. However, arguably the system is now more reliable because the existing switchgear and wiring is no longer a long, complex wiring path carrying full lighting load.

Next up is to install some LED driving lights. After studying dozens of options through vendor websites and rider forums, the best technology appears to be a Clearwater product. Unfortunately they are expensive. The best alternative at lower cost seems to be a Fenix light with Skene controller. I'll cover those in a future post once I can order the bits from Matt Dynes at Motorcycle Innovations and test them on the WR. Can't wait for some real light!