why does a 21' wheel work better off-road

This is not a financially sound decision... Using my BMW R1200GS Rallye as a project bike I dive into the reasons why and the reasons why you shouldn't convert your ADV bikes stock 19' wheel to a 21" rim.

this bike uses suspension straight from Tractive instead of Touratech and Woody's wheels from woodyswheelworks.

For wheels...

It doesn't matter if you are on a Vstrom, Versys, Tiger 1200, R1250GS or any other 19" shod bike you need to watch this.

[casperdevanche]

I ride a Vstrom to places it shouldn't go. I'd advise others to concentrate on getting longer suspension. No point having a front wheel that can get over stuff the rest of the bike can't.

[ErikJ-]

I did de 21" conversion on my 1200GS LC a year ago (as on my 1150 many years ago). Really like it. Now upgraded with Touratceh suspension as well. Only have to do the rear rim as the 170 rear and 90 front is a bit unbalanced (using Bridgestone AX41). But bottomline, the 21" is great. Still have the 19-17" alu wheel set as well.

[magicworld]

I don't understand why only 122k subscribers 😕 your channel one of the best hopefully you will hit 1M soon

[OddvarRykke]

Unless you are a pro, better of keep your adventure bike stock. Buy a dirt bike for the money you save. Bonus: You will learn to ride off road way better.

[day_we_ride]

So Bret Tkacs gets down to brass tacks 👏 I love the honesty, most of us feel the need to justify the expense and argue blindly that yes, it's worth it. Rather than, is it worth it? Not really, unless, for you, in your situation, it's what you want and can afford. Great content Brett.

[bartthomas]

Bret, would you post a parts list? Why stay with a 17” rear? Increased height and tire choices with an 18”. What rim widths did you select? What tire widths and heights? Need new front brake lines? Speedo recalibrate? ABS still works the same I suppose? What is the benefit that extra $$ spent for Woody’s wheels? You’re an awesome teacher, I really enjoy and appreciate your infectious, positive attitude.

[sumporfuk]

Very interesting 🧐. I went the exact ultimate route that you point out. Woody’s 21” Super light hubs, Stainless Steel Spokes & Nipples, Supersized & Superlaced (in for a penny, in for a pound.) Then I got Ted Porter involved and went soup to nuts with the Touratech Extreme manual shocks front & rear. I can’t remember where I read that (and I’m paraphrasing) “There is no magic to suspension tuning, but when you get it right, it’s magical.” After adjusting the sag that suspension setup completely changed the ride of the bike bliss. To be fair, though, it took a quite a bit of tinkering with a lot of other components to get the bike to where it felt like heaven.

[andrewsackville-west]

This is the constant debate around the campfire for this v-strom rider. In the end, for me, the magic is the flexibility of the machine. I find the best traveling is meandering back and forth along the border between the two worlds.

Making targeted investments to extend that flexibility, in one direction or another, makes sense, though maybe not at that price ;-). It's not fundamentally different than replacing windscreens, or seats or other modifications one might do to make their v-strom into a highway touring machine. (Okay, yes, technically, there is a fundamental difference between changing suspension parts and modifying a fairing, especially in terms of safety. But, we're all making our own calculated risks).

Thanks for sharing your opinion on the topic! Having invested in my v-strom suspension, I can attest to the gains available on some of these bikes for playing around on fire roads over on the other side of the mountain range. Cool to see the wheel upgrade reviewed like this.

[karlkrebs]

I told that my Beamer Shop over 4 years ago that they should have a 21" front wheel option or two different bikes.
Sadly they don't really care...

[jonsrmk]

Why not throw an 18 on the rear instead of changing the suspension?

[jayalicekurtmaya]

Another great video Brett. Like the two camera approach. My F650 GS Dakar comes stock with a 21" front and I love it.

[D.E.X]

Just raising the fender 1.5 inches on a DL1000XAL8 presents issues. Do-able, with a new 3-4" longer crossover brake line. But if you did the upgrades on the forks, shocks, and increased both front AND rear wheels to 21" and 19", you still only have 7.2" of ground clearance, the front tire will clear your radiator by less than a half inch if you bottom the front shock and how it would handle at speed on a road while on stilts, I don't have the $$$ to discover. I'll just keep treating it like a late '70's scrambler and save the $$$ for repairs.

[baldandbiking]

Its what I like about my ATAS. Already comes built that way :)

[germaniack]

KTM already has a 21 front on the 1290 SAR, just saying! Give one of those a shot Bret!

[longrider]

Steering and suspension are the most misunderstood aspect of setting up your ride, if you have someone make changes seek out a "suspension" expert. If you have ever ridden something with 12" wheels like a scooter or a monkey, or a yammy TW200 you know it feels different. One of the easiest things to change to gain stability off road is add a set of slightly longer handlebars with a size or two narrower tires, it will decrease your micro steering while digging in off-road. It seems counterintuitive but slightly slower steering off-road is much more stable. That's why sport bikes have short radius bars to quicken the steering which is great on the road. Friction coefficient is much greater on the street and wide tires can be pushed to much faster reaction times, off road you increase friction coefficient by digging in but because terrain can vary so much off road you want your steering to be slower and have more micro control.

[jgscala]

All true, except it depends on the rake angle of the headset. On the 2008 model, I converted to Woody's Wheels 21" Front 18" Rear and the bike handled amazingly well on and off-road. BMW changed their rake angles slightly in 2008 on the GS and GSADV versions. Other years, this change does not work so well as the bike tends to wallow in the turns on the road. At the end of the day, I sold my 2008 R1200GS with 90, 000 miles and shifted to a KTM 790 Adventure R which after many minor modifications is considerably lighter and far better across the board.

[Beemergypsy]

Good video. I'm guessing it doesn't affect the abs then?

[justusgronts]

insane price to lace up a 21" rim to the BMW hub. Old school, buy a 36 or 40 spoke rim (same as the rim) and spokes of proper length and lace it. few hundred $ at worst. Getting the rake and trail right on the steering head is what your talking about on the rest of it. 👍👍👍👍👍👍👍👍👍👍/10

[zenmoto]

Hey Bret. Love your work!! Just had a thought, BMW did make the HP2 Enduro, which is essentially a GS1200 with 21inch front wheel, high front fender, slimmed down in all the right places.

[jvanschie]

i built my front 21 inch wheel and in the sand it was night and day on a bmw 1200gsa 09.Had a spare center and bought the ring from a hp2 and spokes .