Impact forces on sliders

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Lowcountry Joe

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I am about a month away from my FJR purchase. I was talking to a friend with about 2000 miles on his new FJR. I ask if he had installed any frame sliders. He said no, because he was confident that if the bike went down on the sliders, the concentrated force transmitted to the base of the slider during the crash would in turn be transferred to the frame, running the risk of bending or damaging the aluminum frame.

I do not know anything about the technical strength characteristics of the frame members at or near the area where sliders are normally installed. Could my friend be correct about possible frame damage from sliders during a crash?? We all know that just about anything is possible, but on par, is his fear technically sound?

I appreciate your input. Thanks, Joe

 
Where the sliders will really help is a very low speed or stationary drop on the bike. The higher speed get-offs are going to cause a lot of damage - to the bike and you. You can do a search and you'll see that there are a good number of bike drops do to various reasons - bad footing, kick stand not completely extended...etc... The sliders will minimize the damage to the bike in those cases.

Herkypilot

 
Here was the results of my little low siding mishap in 2006.

The slider protected the plastic but not the Yamaha cover. I was glad I had the slider on.

IMG_0736.jpg


IMG_0741.jpg


 
Well, without sliders, all the damage could be directly to the frame. While this could be considered cosmetic, your insurance company will probably view it as otherwise and scrap the bike. So, IMHO, the logic just isn't sound.

 
Delrin sliders OK
Aluminum not OK
I'm not disagreeing, just curious why you say this.

Is it because the delrin will self-sacrifice, while the aluminum will transmit too much of the collision energy to the mount point (the frame we're talkin' about)? That makes perfect sense.

Besides, on my black fjr, the bright aluminum would remind me too much of the chrome that some other styles of bikes use lots of. :p

 
Not only will Delrin sliders sacrifice themselves, but they also allow the bike to SLIDE. An aluminum slider is more likely to dig into the road surface and cause the bike to tumble. With no slider you have the same risk, hard parts can dig in and cause the bike to tumble. With good sliders you have a better chance of riding the bike rather than towing it home.

Also, a delrin slider will absorb some of the side impact of a crash. My experience in a low side crash at about 30 mph: my R&G slider hit the ground, compressed to the point that it actually mushroomed at the base where it attaches to the frame, and then wore down as the bike slid to a stop. I rode the bike the rest of the day and home the next morning.

 
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After reading the posts and looking a bit further into potential frame damage from internet articles regarding slider transmitted energies, it's apparent (also in Fencer's post photo) that frame damage may occur if: -the frame is weak at the point of slider attachment -- if the slider material has little or no energy absorption characteristics--if the slider material tends to grab rather than slide-- if the crash energy is just too much for the slider and slider mount to mitigate--and especially....if all of the slider fluid has leaked out (thanks to Radman for pointing out that potential issue).

So it appears that we may be damned if we do and damed if we don't, depending upon lots of variables. But I would probably have to conclude that after all things are considered, I would rather have high quality sliders on my FJR than none at all. I think that we may have widespread agreement that for accidental low-energy tip-overs or stationary drops, a slider will provide the clearance we need to avoid some otherwise nasty damage without fear of consequential frame issues. As far as crashes at normal or abnormal speeds, we may never know the answer since all crashes are different.

Thanks for all the feedback. Joe

 
Actually, I wasn't going to point it out, but also, they didn't get blood from a turnip, I mean water out of delrin, it either got rained on or washed, as there's a drop of water on the frame, up under the fairing too.

Mike

 
Actually, I wasn't going to point it out, but also, they didn't get blood from a turnip, I mean water out of delrin, it either got rained on or washed, as there's a drop of water on the frame, up under the fairing too.
Mike

That fluid on the frame must be displaced slider fluid, cleverly disguised as water. You can see that this damaged slider has a really bad leak and that spells trouble!! (unless you have a plug-kit for your particular brand of sliders). Just ask Radman, he knows.

 
FJRwreck015.jpg

Aluminum sliders broke my frame
That picture explains exactly what I mentioned in another post about sliders, and how the Slyway aluminum ones are manufactured wrong. If you look at the mounting hole you can see right above it where the slider was in contact with the outside face of the motor mount boss. This fitting was not designed to bear a load on the face of it like that. When the bolt bent, the slider put pressure on the lower smaller portion of the face breaking it off. If the slider was machined correctly it would have had a gap between the slider and the face of the boss which would have allowed for some bending without breaking the frame. This is what makes the Delrin sliders superior. They only have a slim metal bushing inside the Delrin. When the bolt bends, the plastic will contact the frame boss and will be much more yielding than the aluminum.

It angers me that people make junk that is not well thought out and others have to suffer for their lack of understanding.

Rant off.

 
OK, so what about impact forces on certain sliders designed for Generation I FJR's?

The ones I am considering have a triangular mounting arrangement, with two frame mounting points forming the base and the slider located at the apex. From what I read on this thread, it seems like a pretty good design, probably superior to sliders mounted directly to the frame. Any experience with these out there?

(I have laid my '05 down twice, once at walking speed (please don't ask) and once at a standstill. Damage, not counting that done to my machissimo, consisted of paint scratches, now considered "battle scars"), and severe back spasm.) WBill

 
FJRwreck015.jpg

Aluminum sliders broke my frame
That picture explains exactly what I mentioned in another post about sliders, and how the Slyway aluminum ones are manufactured wrong. If you look at the mounting hole you can see right above it where the slider was in contact with the outside face of the motor mount boss. This fitting was not designed to bear a load on the face of it like that. When the bolt bent, the slider put pressure on the lower smaller portion of the face breaking it off. If the slider was machined correctly it would have had a gap between the slider and the face of the boss which would have allowed for some bending without breaking the frame. This is what makes the Delrin sliders superior. They only have a slim metal bushing inside the Delrin. When the bolt bends, the plastic will contact the frame boss and will be much more yielding than the aluminum.

It angers me that people make junk that is not well thought out and others have to suffer for their lack of understanding.

Rant off.

Hey Bob,

Which Delrin composition slider would you recommend for the job?

 
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