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Rim lock or no rim lock?

Posted By: bonneville15

Rim lock or no rim lock? - 07/10/14 6:40 pm

I was wondering if people here are using the Triumph rim locks on their back tires. I am putting a new tire and they told me is alright to leave them out. It is just street use, I do not race my bike. Any advise from the Gurus? It is a 77 Bonneville.

William
Posted By: leon bee

Re: Rim lock or no rim lock? - 07/10/14 7:14 pm

I've put maybe a dozen Brit bikes back on the road in the last few years. Not put a single rim lock back on, and have not had a single problem. I usually grind a new carriage bolt to fit the rim nice to make a fake lock bolt. Opinions differ on this.
Posted By: tri650cc

Re: Rim lock or no rim lock? - 07/10/14 10:42 pm

that's the way I have been doing it since 1973 on dozens of Britbikes have never had one issue with omitting the rim lock.
Posted By: Stuart

Re: Rim lock or no rim lock? - 07/11/14 2:23 am

Hi William,

Ime, people don't have a problem/issue with no rim lock(s) ...

... 'til they have two rear wheel punctures, one on a wheel with rim locks and one without. eek

Assuming they survive the "without", curiously, not only do they never moan about rim locks again, many also wonder how to fit locks to rims without them. :bigt

Ime, if you fit the lock between the rim and the tape and, when fitting or removing a tyre, undo the rim lock nut just to the end of the thread, rim locks aren't any trouble ... and can be a God-send.

Hth.

Regards,
Posted By: Simon750-3

Re: Rim lock or no rim lock? - 07/11/14 2:36 am

You only find out how much you need rim locks when you get a puncture at speed.

As it happens this is exactly what happened to me yesterday at about 45mph.
It squirmed a couple of times and I stopped safely without any problem and the tyre was still on the rim.

The danger of not having locks is that if you brake (or even if you don't) then at some point the tyre will spin on the rim and could rip the inner tube leading to sudden deflation. When flat the tyre could then come off the rim.

I suppose it all depends on what speed you are doing and whether it even occurs to you NOT to apply the rear brake (and yes I didn't remember).

I will be putting rim locks back on. Those extra few seconds it gives you are worth it to me.

Simon
Posted By: dave jones

Re: Rim lock or no rim lock? - 07/11/14 4:12 am

My 67 still has two rim locks (called security bolts in the UK). I don't find them too difficult to deal with when changing a tyre even with the rim tape in the normal place but they do make it a bit more fiddly. A garage changed a tyre for me on a machine once and that was still ok.

It's the front tyre that worries me!

Dave
Posted By: bonneville15

Re: Rim lock or no rim lock? - 07/11/14 6:04 am

To all:

Thank you very much for all your opinions. There is definitely a lot of more experience on you guys from what I have. I been riding since I was 16 and never had a punctured tire the entire time so, I can't really tell about a blow out and don't want to know. I guess I have been blessed. I will put the rims lock back on with the new tire. I do value my hide and life.

If you live down here in Tampa FL, you will have a hard time finding a shop that will do tire with rim locks. I have been turned down 3 times already. Even Harley, BMW, Ducati shops. I am so pissed. What the hell is going on??

William




Posted By: TR6Ray

Re: Rim lock or no rim lock? - 07/11/14 8:58 am

What is going on is -- the kids working in those shops have probably never seen a rim lock before. If you don't want to deal with it yourself, perhaps try a dirt bike shop?

Ray
Posted By: dave jones

Re: Rim lock or no rim lock? - 07/11/14 9:37 am

I had a rear tyre puncture when I was a teen on a 3TA and as I can hardly remember it nothing much can have happened apart from a bit of snaking. I can't remember if that bike had wheel rim locks. I don't suppose a 3TA needs them! I remember refitting the tyre with a rubber mallet. I use levers now.

The garage I went to to have the tyre changed more recently had a fitter who knew about all tyres and wheels, modern, old, car or bike so I was lucky. The only point I was making was that it was possible to do a rim lock wheel on the normal tyre machine. I would have fitted it myself but they got the tyre in and fitting was free.

dave
Posted By: Gordon Gray

Re: Rim lock or no rim lock? - 07/11/14 10:43 am

I wasn't going to say anything but IMO William has made the right choice.

I do all my own tire changing, always have and I have never had a problem with rim locks. To me, they're just part of the job and they're so simple it baffles me when people complain about them.

I have seen the ugly side of not having them installed.

My 1967 B44 Victor Roadster came with rim locks on the rear but not on the front. I was running cheap knock off repro tires (from a known, well respected Brit Bike vendor) and suffered a slow leak at speed (approx 45 mph) on the front. I noticed a slight wobble and slipped forward on the tank to have a look. I noticed the tire was soft so I started slowing down so I could pull off the road and check it out. That's when the SHTF....one side of the bead came loose first.....then the other. All I could do was watch it happen and hold on for dear life. If you want to see what this is like......deflate your front tire....break both beads loose and then try to roll your bike around. Go ahead and try it.

Long story short.....I was going to fall....so I picked out the softest place I could and laid it down. No name man was behind me and thought I had suffered a heart attack. To be honest he was almost right.

I was up in PA on Mike G's OSMR and as soon as I got home....I replaced the tire and ADDED a brand new rim lock to that rim.

Do what you want....it's none of my business, but I'd be careful advising others to do the same just because you've been lucky for years.

Look at it this way....in the past 25 years how many times has your helmet actually saved your life? If the answer is none....based on that answer and that track record could/would you now advise others to not to wear them?


Been there....done that....had the skid marks to prove it.....Gordon in NC
Posted By: Tridentman

Re: Rim lock or no rim lock? - 07/11/14 11:02 am

Never been able to understand why rim locks are fitted on the rear wheel but not the front------
Not getting into the for or against argument but if you think they should be fitted then surely they should be fitted on both front and rear wheels.
Always puzzled me---
Posted By: Gordon Gray

Re: Rim lock or no rim lock? - 07/11/14 11:12 am

Originally Posted by Tridentman
Never been able to understand why rim locks are fitted on the rear wheel but not the front------
Not getting into the for or against argument but if you think they should be fitted then surely they should be fitted on both front and rear wheels.
Always puzzled me---


I need to wait until I can get back to the shop to check....but I do believe they were stock (front/rear)on some BSA's ....but I know for sure not on all of them. I think my problem had a LOT to do with the construction of the tires I was running. They had VERY soft sidewalls and I'm pretty sure that added to the problem.

Stepping down off the soapbox..(because it REALLY isn't any of my business what other people do) blush..Gordon in NC
Posted By: quinten

Re: Rim lock or no rim lock? - 07/11/14 11:58 am

Originally Posted by Gordon Gray
Originally Posted by Tridentman
Never been able to understand why rim locks are fitted on the rear wheel but not the front------
Not getting into the for or against argument but if you think they should be fitted then surely they should be fitted on both front and rear wheels.
Always puzzled me---


I need to wait until I can get back to the shop to check....but I do believe they were stock (front/rear)on some BSA's ....but I know for sure not on all of them. I think my problem had a LOT to do with the construction of the tires I was running. They had VERY soft sidewalls and I'm pretty sure that added to the problem.

Stepping down off the soapbox..(because it REALLY isn't any of my business what other people do) blush..Gordon in NC


While both wheels share mostly similar forces ,
only the back wheel gets subjected to acceleration torque
.
Posted By: Ger B

Re: Rim lock or no rim lock? - 07/11/14 12:41 pm

I'm not in favour of or against the rim lock. I have one on the rear because it's always been there and I never gave it much thought.
But thinking about it theoretically...

Quote
only the back wheel gets subjected to acceleration torque

With respect for your quote, Quinten, the back wheel is the accelleration wheel but:
the front wheel is the more important brake wheel.

If you accelerate a mass from stand still to a certain speed in a certain time,
this asks a certain torque on the rear wheel.
If you brake that same mass from that certain speed to stand still in the same time,
my guess is the torque on the front wheel will be about equal.
As a result the shear force on the connection
between the tyre and the rim will be about equal.

Give or take a few procents for different rim diameters...
Posted By: Tridentman

Re: Rim lock or no rim lock? - 07/11/14 12:55 pm

Actually you brake with a higher degree of deceleration than you accelerate so if you are only going to put rim locks on one wheel logically it should be the front wheel.
And a rear wheel slide is marginally easier to control than a front wheel slide.
So----still puzzled-----
Posted By: quinten

Re: Rim lock or no rim lock? - 07/11/14 7:24 pm

Originally Posted by Ger
I'm not in favour of or against the rim lock. I have one on the rear because it's always been there and I never gave it much thought.
But thinking about it theoretically...

Quote
only the back wheel gets subjected to acceleration torque

With respect for your quote, Quinten, the back wheel is the accelleration wheel but:
the front wheel is the more important brake wheel.

If you accelerate a mass from stand still to a certain speed in a certain time,
this asks a certain torque on the rear wheel.
If you brake that same mass from that certain speed to stand still in the same time,
my guess is the torque on the front wheel will be about equal.
As a result the shear force on the connection
between the tyre and the rim will be about equal.

Give or take a few procents for different rim diameters...


The back wheel is subject to torque forces constantly while accelerating and maintaining speed that the front tire never sees . Plus contact friction may be lost or partially lost , over and over , from hard acceleration or an uneven road suface . The rear tire then experiences varying degees of extra torque as fricton-contact is attempting to be regained by a wheel spinning faster than necessary . The rear tire may go from hard acceleration to hard deceleration in a few tenths of a sec. ( it may lay a patch coming or going ) . It is also be subject to lateral torsion when the rear tire slides in a turn . Steering and common sense stop
Most riders from sliding their front wheels .

In contrast, The front tire has it easy . Under hard braking , It is subject to strong straight line deceleration torque , where some to most of the inputs already sustained by the rear wheel are transfered to the front.

Tire wear is a history of forces applied . With the same compound tires front and back,
Which tire wears first ?
.
Posted By: Old Cafe Racer

Re: Rim lock or no rim lock? - 07/11/14 7:34 pm

In a puncture a rim lock is only going to hold the beads at one point, the rest of the tyre is still free to obey whatever forces are applied to it.

davy
Posted By: reverb

Re: Rim lock or no rim lock? - 07/11/14 8:56 pm

...just reading all these I have many questions; some:
-how do you guys puncture in the road? Seriously; National roads or freeways have perfect pavement/tarmac normally without things on...ok may be on the back roads.

-Too much pressure and hot weather?

-My main concern is always with the small 10 size of my Vespa wheels...very dangerous, but still they do not have the locks...why?; in fact all the scooters that I checked do not have it.

So, are they universal? or depends on the size of the tire?
I have a 21 front and 16 rear; will be enough space for the 21? and for those 10s?
Posted By: Nick

Re: Rim lock or no rim lock? - 07/11/14 9:10 pm

Funny, I've never seen a Japanese bike with a rim lock. Always took them off the Brit-bikes (including my own). There might be some benefit to having them if a tire blows out, but if used for that reason they should be on both wheels, no?

My feeling is that they are holdovers from the days when Brit bikes were also regularly ridden off road or had tires that tended to slip on the rims.

As a CZ and Husky mechanic back in the day, I only fitted them to the MX and off-road bikes. Too, off-road bikes tend to use lower tire pressures, perhaps making the tire more likely to slip on the rim. Many modern rims have serrations on their inner lips that prevent tire slip.

Are any modern MXer's fitted with rim locks?
Posted By: kommando

Re: Rim lock or no rim lock? - 07/11/14 10:43 pm

On 60's BSA's based on my experience the road version has a single rim lock on the rear, the off-road bikes have one on the front and 2 on the rear. I am presuming as the practise is to drop tyre pressures for off roading the tyres are more likely to slip.
Posted By: Stuart

Re: Rim lock or no rim lock? - 07/12/14 1:47 am

Hi,

Originally Posted by Old Cafe Racer
In a puncture a rim lock is only going to hold the beads at one point, the rest of the tyre is still free to obey whatever forces are applied to it.

I can't speak for single rim locks but, on triples, there were two originally and ime they keep the whole bead in place. :bigt

Originally Posted by reverb
-how do you guys puncture in the road? Seriously; National roads or freeways have perfect pavement/tarmac normally without things on

That's the point, punctures aren't "normal"; ime, it's debris - nails, screws, unidentifiable bits of metal, etc. - that cause punctures.

Originally Posted by reverb
Vespa wheels
do not have the locks...why?

Cost. All manufacturers try to increase the gap between what it costs them to build something and what they can sell it for. If they aren't compelled by law to fit something, they'll only fit it if the competition's fitting it.

Originally Posted by reverb
are they universal? or depends on the size of the tire?

No. Sort-of; width and, to a lesser extent, rim diameter.

Originally Posted by Nick
Funny, I've never seen a Japanese bike with a rim lock.

Can't speak for everywhere in the world but early versions of several British models had 'em, Z1 included.

Originally Posted by Nick
benefit to having them if a tire blows out, but if used for that reason they should be on both wheels, no?

Yes. Regrettably, the new ones I've seen for sale aren't as nice as certainly the originals on my T160's. frown

Hth.

Regards,
Posted By: Ger B

Re: Rim lock or no rim lock? - 07/12/14 4:06 am

Quote
subject to torque forces constantly
Which tire wears first?
.

I have to admit you have a point there...

However, not the length of time in which the torque is applied is important.
It's the torque itself, no matter if it's applicable during tenths of seconds or during minutes or hours.
In my trade that's how an engineer calculates the thickness of a shaft,
and other parts where power is transmitted.
The push up force of a ships propeller on the taper of a propeller shaft is an example, or the number of Vee-belts in an E-motor - compressor drive.
The torque is in the equations. The time is not.

grin A young team member of mine races a crotch rocket and said his front tyre wore faster than his rear.
But that was an exception, as he was told by his tyre supplier.
Posted By: reverb

Re: Rim lock or no rim lock? - 07/12/14 12:24 pm

...Stuart, thanks.

Regarding rear tire wearing; besides the forces, in my opinion they wear out fast due to the torque applied, the brake applied mostly; the burn outs, etc; front tire is not exposed to these situations, except the use of the front brake, but normally do not have the same abuse that the rear brake, in where the rubber slide onto the tarmac.
Posted By: DavidP

Re: Rim lock or no rim lock? - 07/13/14 2:14 am

Originally Posted by dave jones
I don't suppose a 3TA needs them!


Originally Posted by Nick
Funny, I've never seen a Japanese bike with a rim lock.


Funny, I remember my first bike, '66 Yamaha 60cc road bike, had rim locks. All of 5HP, and the Japs thought it needed them. I never had a blowout to test whether they were correct.
BTW: I have seen rim locks on the front wheels of dirt bikes. I think maybe the reason we don't see them on the front of street bikes is that they can complicate wheel balancing, which is more critical on the front wheel.
Posted By: Simon750-3

Re: Rim lock or no rim lock? - 07/13/14 3:32 am

There is more info here on Beadlocks

http://en.wikipedia.org/wiki/Beadlock

http://www.4strokes.com/tech/rimlock/

The reason dirt bikers choose to have em is they sometimes reduce the tyre pressures to get over rocks and other obstacles.

Posted By: Ger B

Re: Rim lock or no rim lock? - 07/13/14 4:57 am

Quote
they can complicate wheel balancing, which is more critical on the front wheel

Why is wheel balancing more critical on the front wheel?
Posted By: bonneville15

Re: Rim lock or no rim lock? - 07/13/14 9:50 am

To be honest, I wan't my front tyre to be perfectly balanced. Probably that's why they don't use rim locks in the front.

William
Posted By: DavidP

Re: Rim lock or no rim lock? - 07/13/14 11:24 am

Originally Posted by Ger
Quote
they can complicate wheel balancing, which is more critical on the front wheel

Why is wheel balancing more critical on the front wheel?

For the same reason a front-tire blowout is more dangerous than a rear-tire blowout.
Posted By: John Healy

Re: Rim lock or no rim lock? - 07/13/14 1:14 pm

Quote
For the same reason a front-tire blowout is more dangerous than a rear-tire blowout.


Having experienced both that's a close call.
Posted By: norton bob

Re: Rim lock or no rim lock? - 07/13/14 2:00 pm

I have had 4 punctures while riding, all in the rear wheel, all deflated fully before i managed to stop, all were frightening but i stayed on. The bikes were fitted with rim locks.
Posted By: enigmaT120

Re: Rim lock or no rim lock? - 07/13/14 3:40 pm

I've used nothing but tubeless tires on my Triumph for a really long time. I've had several flats on the rear with no rim lock, and it didn't even break the bead. I was able to ride on it, those tires are so stiff even without air. I think if I were running the original tube type tires that would be a different story.
Posted By: Ger B

Re: Rim lock or no rim lock? - 07/13/14 4:34 pm

Quote
For the same reason a front-tire blowout is more dangerous than a rear-tire blowout


A blow out is a blow out, David, whether the wheel is balanced or not.
The effect of a blow out, front or rear, has nothing to do with the wheel being balanced or not.

So you did not answer my question: Why is wheel balancing more critical on the front wheel?

The only reason might be: There is more mass in the rear suspension than in the front susspension.
So the effects in te rear will be less transmitted to the bike / rider than in the front;
where in the front the effects will be transmitted directly to the steering bar / hands of the rider...

No arguments for or against the use of rim locks,
since balancing is not more or less complicated with or without.
The only difference is you need a bit more weight on the oposite side of the rim lock.
Posted By: kevin roberts

Re: Rim lock or no rim lock? - 07/13/14 4:46 pm

back in the middle ages, i took off the steel rim from the rear of my T120 and replaced it with a shouldered borrani. on the advice of the clymer bonneville manual, i dumped the rim lock and just drilled the borrani for four sheet metal screws on each side.

been okay for a long time, but i can't recall whether i've ever had a flat with it or not. i always run new tubes whenever i change tires, and so far perhaps i've been luckier than some.
Posted By: bonneville15

Re: Rim lock or no rim lock? - 07/13/14 4:53 pm

Enigma:

I kind of baffled. Can you use tubeless tires on a spoke rim??? How do you do it? Do you have lester wheels?? I have been trying to get some lesters but no luck.

William
Posted By: desco

Re: Rim lock or no rim lock? - 07/13/14 5:15 pm

Not real complicated. You put a tube in them. Don't forget a new rim strap.
Posted By: bsatrinor

Re: Rim lock or no rim lock? - 07/13/14 9:00 pm

at 69 i still change my own tires,,,dont use rim locks any more,,,they only throw your tire out of balance,,,dont need them ----if you dont do wheelies and slip the tire on the rim,,,,,if you are using K70 tires,,,they are soft as mush when they deflate on you,,,cant ride them home,,,-----switch to a good firm tire like harly uses,,,,the wont squish and throw you------even K81 are a lot stiffer than K70
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