Rim lock (security bolt)

Larry S

Larry S

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I’m getting ready to install a new rear tire and want to know if I can eliminate the rim lock. I’ve read that it really doesn’t do much. In the event that I do eliminate it, what do I fill the empty hole with? Thoughts, opinions?
 
Only my experience and thoughts, don't know how correct I am. Presume we talk about spoked wheels with inner tubes.
Rim locks are used to prevent tire to slip on rim. Which can tear off the the valve.
Could happen on high power bikes or bikes with extremely effective brakes.
I only have rim locks on the Victor Specials that has tyre pressure 16 psi as per owners' manual. On soft surfaces even lower.
All modern enduro bikes in the barn has rim locks as they go with low pressure.
Never had any on the road bikes. Mainly because trouble fitting and balancing.
Do tyre slip? Rarely. Though I check tyre pressure at least every week, on the racers before every start of the bike.
Always fit tyre so that valve stem points to centre of wheel!
I never tighten the nut on the valve stem. About 3 turns loose. As long the valve is straight I know that tyre has not slipped. If stem is angled remove wheel and correct. Takes much time.
Hole in rim. Rim tape enough. About two pounds force trying to push inner tube through hole.
Sometime I use electrical tape instead of rim tape or even use both.
 
Larry S said:
I’m getting ready to install a new rear tire and want to know if I can eliminate the rim lock. I’ve read that it really doesn’t do much.
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It really doesn't...until....without one, there's a fast deflation caused by a large nail or similar at hight-speed that by the time it's noticed that something is not as it should be, work out what the 'something' is and then react (hopefully not by applying the rear brake) by which time the tyre pressure could be down to 10 psi or less when the valve can rip from the tube as the rim begins to spin inside the tyre and with no pressure the tyre drops off the rim beads often resulting in the rear end becoming practically uncontrollable.

In this situation, the security bolt/rim lock should not only prevent the rim from spinning inside the tyre but also keeps part of the tyre up on the rim bead allowing at least some control over the rear end as the bike is brought to a hopefully still upright, stop.
 
I had exactly the experience described by L.A.B. on my ES2 a year or few ago, except the bit about staying upright. Rimlocks for me.
 
After many years of not using them I have gone back to using them despite the PIA they are at fitment time. The old Dunlop type seem easier to deal with than the new made alloy ones.
They only go on the rear which is odd with all the stopping power available with modern front brakes. As we enter fogeyhood, safety becomes something I try to think about.
 
I use one because I think there's more (even if only imaginary) chance of the tyre moving due to a botched gear change or stall, rather than being ripped off by the awesome torque :)
 
I figure there was a reason the mfgt put them on, so unless I see data proving they are not needed, they will stay on.

Slick
 
PITA. I don't use them.
Shape a stainless bolt so the head is very shallow and use it to fill the hole and replicate the look of the original.
 
Hmmmm let me see
How many bikes use rim locks these days?
I suppose modern bikes don't have the power or torque that a commando has ?😉
 
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I just dismounted a 400-18 that didn't have rim locks. As hard as it was to get the tire off, I don't see the need for rim locks.
 
baz said:
Hmmmm let me see
How many bikes use rim locks these days?
I suppose modern bikes don't have the power or torque that a commando has ?😉
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Actually, most/all modern rims have a designed in safety rim that grips the tire bead much more than our OEM rims. My 18" aftermarket alloy rear rim had radial knurled serrations where the bead contacts. I have had several tire deflation events, so far only on the modern bonneville which has tubed/spoked rims, no safety lock but have the modern rim safety lip.
All but one deflation were rear tire only and I was able to control the slow down easily. Once I manged to limp bike underpower a few blocks to a motoshop for repairs without much trouble.

On the day a cop'er pulled a spike strip across the highway just as I went by at 100 Km/h, the bike also never went out of control, I just let it glide in deadstick and some five hundred feet later I stepped off to find both tires dead flat. Closer inspection showed two fang like tubes stuck into each tire surface.
 
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Tornado said:
Actually, most/all modern rims have a designed in safety rim that grips the tire bead much more than our OEM rims. My 18" aftermarket alloy rear rim had radial knurled serrations where the bead contacts.
Click to expand...
Yes I've seen serrations on some rims
But for the last 46years I have thrown them away without issue (as yet) but anything could happen
 
Tornado said:
Actually, most/all modern rims have a designed in safety rim that grips the tire bead much more than our OEM rims. My 18" aftermarket alloy rear rim had radial knurled serrations where the bead contacts. I have had several tire deflation events, so far only on the modern bonneville which has tubed/spoked rims, no safety lock but have the modern rim safety lip.
All but one deflation were rear tire only and I was able to control the slow down easily. Once I manged to limp bike underpower a few blocks to a motoshop for repairs without much trouble.

On the day a cop'er pulled a spike strip across the highway just as I went by at 100 Km/h, the bike also never went out of control, I just let it glide in deadstick and some five hundred feet later I stepped off to find both tires dead flat. Closer inspection showed two fang like tubes stuck into each tire surface.
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A few years ago I had a flat on the rear of my 08 Thruxton, in the middle of a long 65 mph curve. At first I thought must have hit something slick in the road, by the time I got off the road the tire had spun and ripped the valve stem out of the tube. Even though it was fairly uneventful I sealed the spokes and converted to tubeless both my modern bikes. Because the Norton doesn't have the safety beads I'll stick with the aggravating bead locks.
 
Looks like differing safety views on the subject so far .
They are quite awkward to fit , so I go without on the rear , stock rim and spokes .
I use a high quality Michelin tube and thick rim band . Then I cut and glue a piece of extra rubber under / on the rim band , at the rim lock hole . This is to stop / prevent any potential bulging of rim rubber outwards at the hole . Feel / the hole itself for any roughness of cut and sand it smooth if necessary first . Stephen says he fits a smoothed out head bolt to fill the hole which would work fine as long as the interior head is very smoothed out . You don't want anything to chafe or rub through to the tube itself . My 2 cents .
 
I use WM-4 Morad rims 19" front and back. I don't use the rim locks or drill for them on these rims. The inside of the Morad and Akront's were serrated radially where the tire sidewall contacts the rim. More than enough grip to prevent any tire movement with the rim. The old dunlop rims were polished chrome plated.
just saying.
 
I been riding my Norton for over 40 years now with Akront alloy rims without rim locks, yes they have the SR sidewall groves bur so far have never had a flat with tests rims (touch wood) had a stage where I had one new rear tyre with the stock rims where I went through a stage of many flats tyres (I got good at fixing flats) ended up finding it was a faulty tyre a small slit inside sidewall causing the flats the tyre was replaced for free (mine you that was after about 10 or more flats).
My 2016 Triumph Thruxton has alloy rims without rims locks and the same with my old 2013 Thruxton and I had a rear flat on that never slipped on the rim when it went down.
Besides if it did tear out the valve when flat you going to replace the cube anyway but never tore a valve stem yet, can understand having rim locks on dirt bikes as they run on low pressure I run my dirt bike tyres at 10 to 12lbs Max in the dirt.

Ashley
 
Any truth to reduction of rear tire punctures by running an extended mudflap off front mudguard? Have one on the Commando and so far so good with 22k miles. Bonneville has no extended flap and several rear punctures in 72k KM's.
 
I got my tire mounted and balanced today and elected to delete the rim lock. I used a stainless carriage bolt with a flat washer and nylock nut to fill the hole left behind after eliminating the rim lock. I used a file to round off the corners at the base of the bolt. It fit perfect. A lot of wheel weights were removed to achieve a correct balance but in the end it came out right. I’m going to reinstall the wheel tomorrow and go on a nice long ride.
 
Larry S said:
I got my tire mounted and balanced today and elected to delete the rim lock. I used a stainless carriage bolt with a flat washer and nylock nut to fill the hole left behind after eliminating the rim lock. I used a file to round off the corners at the base of the bolt. It fit perfect. A lot of wheel weights were removed to achieve a correct balance but in the end it came out right. I’m going to reinstall the wheel tomorrow and go on a nice long ride.
Click to expand...
I've done the same, using a round top carriage bolt and nut to keep the original look without the extra weight.
 
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