Thinking about it or you have no clue what that is?
Keep reading, we will cover what it does and why you might want to do this easy modification on the DR.
What is a rim lock for?
A rim lock is a simple part that is used to "lock" the tire on the rim.
If you come from the dirt biking world you already know all this.
Otherwise, if you are a new rider or simply coming from the road side of motorcycling, this could be all new to you!
As strange as it may seem for the novice, the tire can actually slip on the rim when a high torque is applied on the wheel (like hard acceleration or braking) while the tire is holding firmly on the ground.
The situation is typically found when dirt biking as you can ride with as low as 6 to 12PSI.
The air pressure that is supposed to hold the bead of the tire against the rim is no longer so effective. We then came up with a mechanical solution to actually hold the tire on the rim no matter the pressure.
This part sits inside the tire, under the tube and simply pinch the inner side of the sidewall against the rim thanks to its angular shape. A threaded rod goes through the rim so when tightened, it presses the rubber shape against the tire.
The picture below should help understand how this works:
Why would you want one on a DR650?
You'll have noticed that the only thing sticking out of the rim is the valve stem and there is no opposite hole with a rubber cover either (on some bikes the wheels have a second plugged hole available to install a rim lock as an option like the other bushpig Honda XR650).
Installing one on the DR650 simply comes down to drilling a hole so the real question is installing one or not and why?
At Bushpig Performance, everything we do is about building a simpler, lighter and more reliable bike
Everything we develop or modify on the DR is about building a simpler, lighter, and more reliable adventure bike whether you are a weekend warrior exploring the backroads or prepping to go on an RTW trip.
From this standpoint, we believe that having a rim lock on the rear wheel only is a modification worth doing.
Pros:
- peace of mind that you while never reap the valve stem.
- ability to run ultra-low pressure to get out a really low grip section on the trail.
- possibility to carry on with a completely flat tire without incurring too much damage to the tube until at a safe spot for repair.
Cons:
- adding extra weight on the rear wheel.
- adding an extra step for tire change.
- absolute need to balance the wheels (but you should do that anyway!).
Why not the front?
The DR is not a dirtbike.
It shouldn't be ridden for long periods of time with ultra-low pressure in the tires because they will deform and overheat quickly under the weight.
There is no point locking the front tire since you won't spend time in this situation, like braking hard with a 6PSI front tire...
But locking the rear can be advantageous for long or tough off-road trips, or anywhere in remote terrain where unexpected situations could happen.
A rear rim lock can increase your pig reliability by preventing damaging the rear tube and tire because of slippage on the rim.
Obviously, if you only ride the tarmac, mild gravel roads or you are always close to town, there is no real advantage with installing one.
Hopefully, you have now some elements to make up your mind about it and decide for yourself.
Here is the complete tutorial to install a rear rim lock
Tools and supplies needed
Wrench size 24mm to take the rear wheel off
Tire iron set and other tire-changing tools you might like
Air pump/compressor
Wrench size 12mm (most rim lock nut)
A drill and metal drill bit size 10mm or 3/8"
A rim lock
What rim lock to choose?
Even though it seems like a simple part, you will find many sizes and price levels ($10 to $35CAD).
The most important is to choose the correct size which is 2.5" for the DR650 with an original rear wheel.
The more expensive ones are lighter, made with either plastic or titanium bolt and aluminum body. They also come with a nicer nut and washer (see picture below).
Half the weight of conventional rim lock available in the shop: Warp9 Titanium Rim Lock 2.5"
Preliminary tasks
Remove the rear wheels and take the tire, tube and rim strip off.
Step1: Locate and drill
Find the valve stem hole and go on the opposite side across the hub.
On the DR you will end up on a spoke, so choose the direct next space beside this spoke and mark it on the exterior of the rim.
Then from the outer side, simply drill the rim in the middle like the valve stem is.
Clean the sharp edge and burrs of your hole if needed.
Step2: Reassemble!
The last step before putting back the wheel together is to cut a nice extra hole in the rim strip. If your's is looking dire, it's a good idea to replace them.
TIP: A good technique to cut a nice round hole in the rubber band is to put it in place (align the valve hole first) and then press the threaded rod of the rim lock in the new hole with a rotating motion.
It will mark the hole nicely if not cutting it against the edges so you only have to finish it with a sharp knife.
Proceed to reinstall the tire as usual but you now have to take an extra step with the rim lock.
Start with the rim lock mounted loosely then put the tire as usual.
The only difference is that you need to push the rim lock up in the tire to make sure the sidewall can drop down on the rim.
Once the tire is on, pump the tube to pop the tire in place, THEN you can tighten the rim lock nut, not too hard but firm.
And remember to balance your wheel! This is a MUST! Otherwise, you will have weird vibrations, unwanted effects on suspension, and overall not a good feeling from the bike.
See our How to balance your wheels article for guidance.
Now enjoy a ride free of tire slippages and torn tubes!
Good point Jonathan! Loads of information in this article on rims.
I agree on the fact that I find tire fitting pretty hard 😅 on those wheels but even though they grip pretty well, I found in real riding situations that the rear tire could slip when really deflated or flat.
The DR650 has a lot of torque, combined with good grip terrain/new knobbies, if you need to ride flat to get out of a situation, the rear tire can spin and rip out the tube valve stem.
Hence why the rim lock as a preventive measure in the back only. Not needed indeed, to simply ride with lower pressure.
Ahhh, but…. The profile of the wheel rim is hyper-relevant to this subject. If you look at the cross section of wheel rims you will see in the centre there is the deep well where the spoke nipples go through and screw onto the threaded ends of the spokes (don’t forget to install the rim tape - absent from the photo at the lead of this article - it stops the spoke nipples chafing holes in the inner tube). The purpose of the deep well is to give room for the tyre bead to go into while you’re trying to persuade the bead over the rim on the other side of the wheel.
This bead well is common to all…