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I hear frame sliders can get stuck into the grass, flip the bike, and cause worse damage during an out of track slide. But then all CSS bikes have them.

 

What's your take?

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You can't really predict physics. Sometimes they help and sometimes they don't. It really depends on the type of crash and the situation if they are helpful or not. Motorcycles aren't crash tested but there is some general knowledge out there from other people's experiences. If you look at most race bikes they are equipped with sliders. That's good enough for me.

 

The underlying purpose of them is to protect frames and engines rather than bodywork. Cast aluminum motorcycle frames will easily develop hair line cracks if they are stressed the wrong way. It's difficult to weld cast aluminum and VIN numbers are tied to the frame making replacement complicated and expensive.

 

If you think about it it's all about momentum. If a bike has so much momentum that it flips because a frame slider catches what stops a bar end or a rear set from also hurling the bike in the air? Nothing you can do will overcome that momentum when you have a bike moving at speed.

 

Personally I think sliders help protect the bike's most important parts during a crash. One of the first things I did was order sliders when I took delivery of my new S1000RR. I hope I never need to find out how effective they were.

 

P.S. Frame sliders by themselves are not as effective as a comprehensive set of sliders for a bike. Engine case guards, Axle sliders and other protective parts all work together to minimize the damage when things go sideways.

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I believe (and really, it's just that—a belief) that the long sliders are far more apt to cause a flip than ones that are lower and more rounded. I have the GB Racing "race" sliders for this very reason (they also make a taller version for street—my thinking is this is because street riders care more about their plastics).

 

The big toilet-paper-roll sliders seem like trouble to me.

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I believe (and really, it's just that—a belief) that the long sliders are far more apt to cause a flip than ones that are lower and more rounded. I have the GB Racing "race" sliders for this very reason (they also make a taller version for street—my thinking is this is because street riders care more about their plastics).

 

The big toilet-paper-roll sliders seem like trouble to me.

 

I tend to agree with you on this. I went with the Woodcraft sliders. They are lower than the ones you see on the street and have rounded edges.

 

I think the street going ones are so large for a couple of reasons. First is the idea of protecting the bodywork which is a false economy if you crack the frame. The second really is just appearance. Frame sliders tend to add at least 10-15mph of speed capability to any parked motorcycle especially when teamed with lots of stickers and a set of track take off's. :)

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Well - here is a war story for you - my husband had a low side recently with the BMW S1000rr, it has the R&G frame sliders, which are the same ones the school uses. By the time the bike actually touched down (he tried pretty hard to save it!) it was probably going 35 mph. It slid and then it spun around. He picked it up and rode it back to the pits. The frame slider had been ground off about halfway, and there was NO OTHER visible damage on the bike. No fairing or paint damage, no lever damage, nothing. He took it to re-tech it and they teased him about it, asking him if he threw himself under the bike to save the paint. :) He rode it in the next race ten minutes later. I have no doubt whatsoever that the slider saved him many $$ in paint and fairing damage, and probably saved his case-cover too.

 

I've seen a number of low-sides where the only damaged parts are frame sliders, bar ends, and ground foot pegs and scraped levers. That is minor stuff that can be fixed in minutes, and the bike is rideable even before the repairs are made.

 

My take is that frame sliders, bar ends, spools, etc. are there to save you from minor-to-medium damage in low-sides, low speed falls, and parking lot tip-overs (which do happen, even to experienced racers, I've seen it happen when they forget to unplug something, or catch a handlebar on a EZ up tie-down, or make an error with a stand, for example).

 

For a high speed crash where the bike slides off the track, or a high-side... all bets are off, some bikes get lucky and survive pretty well and some catch a certain way and break all kinds of stuff. I can't speak to the shape of the sliders, except to say that I've seen some crashes where those long thick R&G sliders get ground halfway off or more and still have enough length to keep the paint off the pavement.

One caution is to research the type of sliders - if the slider has a thin, cheap bolt, or if the bolt-hole in the BIKE is too small, in a crash the bolt can bend or break (which smashes the slider into your fairing and cracks the fairing) or can rip the bolt out of the frame, causing damage to the frame. The S1000rr does not have a problem in this regard but as I recall some of the older ZX6Rs did have an issue.

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I have worked with Will and Daniel in the garages of NJMP for the past four or five years and I am amazed how much those R&G sliders save most of the bikes that have gone down there. Not all of course as Hotfoot said but they do seem to offer a level of protection that makes the investment worthwhile. There is no way Will would put them on every School bike if they didn't.

 

Rainman

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Seems more right than wrong to have them on!

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Seems more right than wrong to have them on!

Yup! I have frame sliders, spools, and engine case covers with the hopes that a minor incident will be easily dealt with. I've had a bike go down and grind a hole in the engine case. I would call this "bad". Thankfully, no bad stuff made its way inside. It was that incident that made me buy everything under the sun.

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So it looks like the consensus is yes for low sides and minor slides, but the question is still open for high-speed and out-of-track crashes.

I did see a Triumph 675 frame cracked after an out of track slide: speed was probably higher than 50Mph, the slider got stuck into the ground during the slide, causing a bike flip and cracking the frame where the slider was anchored. I hear a broken frame makes it for a very costly repair.

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This is probably a good place to point out that "Race Plastics" which are made of fiberglass and possibly Kevlar, are much more resilient to damage than stock plastic plastics

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So this weekend I was chatting up a fellow S1000RR owner in the paddock at a track day. We were talking about frame sliders and my Tecbike belly pan. Unfortunately the session after our chat he crashed. His bike made it through his "agricultural experience" without a single scratch or ding.

 

As for the broken frame. Just to give you an idea of the cost one of my R6's developed a crack in the frame. I'm somewhat emotionally attached of the bike because it's the first sport bike I ever bought. The used frame was $1000+ and the labor cost to replace it will likely be $1000+ as well. This is for a 10+ year old "throw away" R6. The bike has to be completely disassembled for replacement. You can get frames very cheaply but once you need a title to be able to register the bike the costs go up FAST.

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Im for sliders with a tendency to glide on the ground on touchdown and ground off evenly than make the bike rotate around like a top (round protruding sliders are very guilty of this) .


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Im for sliders with a tendency to glide on the ground on touchdown and ground off evenly than make the bike rotate around like a top (round protruding sliders are very guilty of this) .

 

 

 

Ah, I wonder if that is the reason for the teardrop shape of those R&G sliders, I never really thought about it but maybe that helps the slider slide straight instead of putting the bike into a spin.

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Im for sliders with a tendency to glide on the ground on touchdown and ground off evenly than make the bike rotate around like a top (round protruding sliders are very guilty of this) .

 

 

 

Ah, I wonder if that is the reason for the teardrop shape of those R&G sliders, I never really thought about it but maybe that helps the slider slide straight instead of putting the bike into a spin.

 

 

There has been instances where a hi speed lowside caused the bike + round protruding slider to spin and hit said riders, with disastrous results...

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There has been instances where a hi speed lowside caused the bike + round protruding slider to spin and hit said riders, with disastrous results...

 

 

So an interesting thought here. I wonder how many of those bikes were equipped with additional sliders other than just the frame sliders? One point of contact rather than several can cause all sorts of unexpected problems.

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The short answer is yes they help keep the cost of damage down. A couple of things though, like the catch and tumble the bike? Yes the point of contact is higher than the bike sliding on its side BUT that only counts if the bike is sliding backwards ( tank first) and if it's going away from the tires it's going to turn over anyway. The other is that the slider or bolt will actually damage the frame or engine mount, Yes and no, it depends on the manufacturer. I made my own for years sizing the bolt and sliders to give but protect. R&G are simply the best engineered sliders I have used. We have not had one damage an engine mount in five years. What that means is the bolts give and bend correctly, too stiff and the bike will give. That bending bolt has done some minor damage to bolt face on the frame but it is of no consequence.

Yes again to the package effect of sliders on all the high points, the more the better. We have had many bike go down and need only the sliders or a case cover to be ready to go again.

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