WR250R: Less May Be More

This entry is part 8 of 19 in the series Adventure Rider Issue #30

Is the WR250R in RideADV spec the best sub-450cc adventure bike in the world? Nick Dole applies some art and science to Yamaha’s small-bore adventurer.

RideADV boss man Greg Yager (right) saw the 250R and requested two as pre-run bikes from YMA. The conversion rate from riders who try Teknik-modified WR250Rs on RideADV events is 100 per cent.

I remember when the WR250R came out in 2008. There was some advertising but not much hype and the model seemed in no-mans’ land. It was substantially less powerful and had a lower-spec everything than the WR250F, and no racer or ex-racer would want that. It was liquid-cooled with a tall seat height so it didn’t appeal to the farmers buying the TTR250. Was it a commuter? A single-cylinder 250cc trailbike with no wind-screen as a commuter? No thanks.

I do remember Darren Thompson, Yamaha Motor Australia (YMA) head tech, discussing the new model with me, and he mentioned the manufacturer’s service intervals were 25,000km between oil changes(!) This had been knocked down to 10,000km for Australian release. YMA told Japan it was going to change the schedule, and Japan thought there was no need because 25,000km intervals was what the engine was designed for. YMA stuck with 10,000km oil changes and left valve adjustment at 25,000km.

A cutting remark

The WR250R was a Japanese domestic model that escaped into other markets.

Unlike many trailbikes we now see from the Japanese Big Four that have a large content, or are entirely, assembled in Thailand, the WR250R is entirely built in Japan, so it was expensive at $10,499 when released in 2008 and stayed at that price until 2013.

In 2012 Yamaha-sponsored ride organiser RideADV was using 660 Ténérés as pre-run bikes. The nature of course pre-running is exploring trails and trying to join tracks on maps. The 660 was heavy when stuck on a hill and a handful when the track being followed suddenly wasn’t there. RideADV boss man Greg Yager saw the WR250R and requested two as pre-run bikes from YMA. A chainsaw (originally out of my shed) was mounted on the back of one and Greg reported that the bikes were actually very good, but the shock was so bad the chainsaw kept falling off.

Nick Dole

Long-term project

I had worked on a few WR250Rs for customers from 2008 with mediocre results.

The forks were a 46mm USD KYB that looked like the 1996-2003 YZ units, but had cartridges the same size as the YZ85 (that’s what the YZ range had in 1988). The shock wasn’t much better.

It wasn’t a KYB shock, it’s a Soqi, a wholly Yamaha-owned subsidiary company that makes suspension units for the more budget models.

The shock has a rebound adjuster straight out of my 1983 YZ125K.

That may sound dismal, but it’s not. There are very few adventure bikes with stock suspension componentry I’d describe as anything other than rudimentary. This doesn’t stop me from analysing the stock components on the shock and fork dyno and making them perform for a different purpose than the factory intended.

Six years on and many suspension settings later we now have a very well developed WR250R. The forks didn’t turn out to be a problem with the ‘little’ YZ85 internals. I just needed to mount the forks on the dyno and start working.

The shock was harder. We tried two different main pistons and 30 setting changes in over four years. The problem, in hindsight, was a lack of low-speed damping control. One of the questions I always get about our shock dynos is, “How fast do they go?” as if that’s an important measure of the dyno’s ability.

It has the same relevance as if you asked an engine tuner how much horse-power his chassis dyno could handle.

It’s about the least-important question you could ask.

It’s an ‘adventure sprint bike’
Teknik experimented with lowering the shock and settled on a 10mm lower shock length than stock.

Q&A

For adventure bikes with a purchase price of under $10K you’ll get very little.

At $15K it’s still quite lean in terms of stock suspension componentry. So the WR250R has old motocross technology, but it’s still well advanced compared to a trailbike and is actually pretty good by adventure-bike standards.

Why not just start with a 450 enduro bike?

We did that last year: three 2017 WR450Fs. We tried to tame them with big tanks, mild mapping and better seats. Were they fun for three hours? Yes. Were they fun for eight hours and successive days? No. Can you compare a hard-edged WR450F with a WR250R? Yes and no.

They’re both blue off-road bikes with compliance. That’s about where it stops. The 250R is easy to ride all day and doesn’t need the maintenance a WR-F does.

It took American Tim Hollis a while to figure out he could hold the throttle on and just ride up trails with no care.

So what do we actually do to WR250R suspension?

Let’s start with the fork.

The 250R already has 4.6N springs.

That’s stiffer than a DR650, Ténéré 660 or KLR650. It’s perfect for a big tank with a rider up to 100kg. We have 4.8N springs for heavier riders. We can thank the road designation of the WR250R for the stiff fork springs.

Where do we change the fork then? The big changes are to the damping character.

We still use 3wt oil, it’s a complete reinvention of the shims and valves.

Then we run the fork on the dyno to ensure it meets the targets. Not every fork is the same, so sometimes we need to change our settings a little to meet the targets. A fork is a bunch of parts that all have tolerances. This can result in ‘tolerance stacking’, where the sum of the tolerance parts creates an assembly that needs loose tolerances. That’s no good for us. The dyno doesn’t lie, so if we need to pull the forks down four times to get the targets, that’s what we do.

We do also change the setting a little for female riders or older riders who want more comfort.

Rear

The shock was the sticking point.

The stock spring was okay at 81N.

It’s good for an 85kg with no gear or two 55kg Japanese people. We leave the stock spring for women and light men.

Most people use a 90N rear, but we have a 95N and 100N as well for the heavier folk. Note the spring rate has nothing to do with how fast you ride.

A spring just supports a mass. We do everything else with damping.

We found we could run a lot more damping character than stock and it didn’t make the shock harsh, in fact it was the opposite. More damping made it more compliant.

We modified the rebound adjuster in 2015 and started to get great-handling 250Rs. We experimented with lowering the shock and settled on a 10mm lower shock length than stock – that’s 25mm at the axle. It brought stability to the chassis, more traction and no situations where the seat hit you in the arse.

We do lower it more if you need it.

We also, like the forks, give the ladies and older gents a softer setting.

“The dyno doesn’t lie, so if we need to pull components down four times to get the targets, that’s what we do.”

So what’s a modified 250R like?

It’s no motocross bike, and no competition bike. It still has to be an adventure bike, and that means ‘comfortable’. Greg coined the phrase a few years ago: ‘adventure sprint bike’. It’s great to take away for a few days. Would you ride it from Sydney to Cairns? You could, and it would not be fun. Would you ride a BMW GSA on some of the trails the 250R is in its element on? You could, but you’d be looking for a way to get out of it and not enjoying the ride.

American Tim Hollis was on the WR Rally and he’d never ridden a modified WR250R. His personal bike is stock.

When he was on the Thursday pre-ride, he’d ride up the edge of technical sections while the other WR250R riders blasted up the middle, not worrying about the holes, small rock steps and tree roots. In Tim’s mind a WR250R couldn’t do that. It took him a while to figure out he could hold the throttle on and look ahead, and just ride up trails with no care. He stopped thinking about the suspension and concentrated on riding. That’s a win for the late nights running a shock dyno on WR250R shocks.

Do I accept any responsibility for Tim’s tree-hugging activities?

Well, he felt good enough to chase Greg Smith on a WR450F and he thought those two spoon drains were close enough to double.

No responsibility here. It sure made us laugh, though.

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