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Discussion Starter #1 (Edited)
First off, this thread is to share my personal experience, not intended for any other purpose. Please keep your opinions private. If there are any questions regarding my measuring methods, I’ll answer them as best as I can. Please correct me if my measuring methods are flawed.

After reading a thread about the potential of a certain design of frame slider piercing the water jacket, I got curious. I noticed that even with the proper torque 55nm applied to the bolts, I was still able to rotate the slider puck with my weak hand with reasonable ease.

I pulled one slider off to take some measurements. (Not very scientific, but I did my best with a valid calibrated caliper)

Clarence required from the slider side.




Actual clearance in the frame hole.

I did my best to measure the outer diameter of the hole (most likly where the mounting bolt will contact the bottom) and not the center.




With +/- 1mm, I feel it's a bit too close...

I also noticed that the aluminum spacer inside the slider puck didn't sit flush (shallower) with the slider puck, hence there may leave some room for compression on the bushing material. (Further reducing the clearance before bottoming out the mounting bolt on the cylinder head)

I did my best to take a picture of the bottom of the cylinder head hole....





Looking at the bottom of the hole, I saw some rotational (possibility from a “interference fit”) marks at the very bottom, normally there would be a machining surface done by the tap, but the surface were rippled and seem to be done either by the mounting bolt or a very poor condition tap.

Not sure if anyone can see it in these pictures well , but I have some very high definition version of the pictures. (3.6 megs each)

For some added safety measure, I added a 2mm thick crush washer (the kind used on oil drain plugs) to the slider mounting bolt to give some extra clearance. After re-torque, now I'm unable to rotate the sliders by hand.
 

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Also be aware that these kind of sliders have been known to pull out the threads of the head in an impact. Although potentially repairable, a 2-bolt system is safer still.
 

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Wouldn't it be easier/better to take off 1mm off the bolt with a grinder?
 

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Also be aware that these kind of sliders have been known to pull out the threads of the head in an impact. Although potentially repairable, a 2-bolt system is safer still.
i'm not sure i understand how the 2-bolt system (bolt-inside-a-bolt) provides superior protection for the aluminum threads of the head. can you explain the theory behind this?
 

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Yeah, same difference i didn't have a grinder handy.
Either way get's the job done and that's all that matters. Cool Beans.

I'm assuming you are using a Motovation kit by the pics.
 

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yeah i read that article, but it does say *why* that makes a difference. it doesn't add up to me. if the "slider bolt" is bolted to the "head bolt", and the "head bolt" is bolted to the aluminum threads, how is that any different (from a force/phsyics standpoint) from having just a single bolt?

two bolts (one bolt rigidly attached to another bolt) is the same as just having one bolt (as far as distribution of forces into the threads goes).
 

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To me the only argument is that, if there is enough force to rip out the slider from the engine casing the dual bolt configuration will break at the much smaller bolt rather then the larger one attached to the engine case causing less damage to the engine case (but more to the frame). I guess the argument is that the engine is more expensive to fix than the frame and engine covers. If you notice most 2-bolt system use a much smaller "puck", this is because that smaller bolt will break very easily if you put a Motovation sized "puck" on it due to the leverage it generates. There are pros and cons to both setups.
 

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Discussion Starter #10
I guess the intent of this thread is not to discuss who's kit is good / bad, but to show that with this style of frame sliders you need to make sure that there is enough clearance to properly install the frame slider without risk of damage.

The issue here does not point to the any one frame slider kit, but a combination of production tolerances on both the bike and the slider kit.


Either way get's the job done and that's all that matters. Cool Beans.

I'm assuming you are using a Motovation kit by the pics.
 

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To me the only argument is that, if there is enough force to rip out the slider from the engine casing the dual bolt configuration will break at the much smaller bolt rather then the larger one attached to the engine case causing less damage to the engine case (but more to the frame). I guess the argument is that the engine is more expensive to fix than the frame and engine covers. If you notice most 2-bolt system use a much smaller "puck", this is because that smaller bolt will break very easily if you put a Motovation sized "puck" on it due to the leverage it generates. There are pros and cons to both setups.
ok, the thing about the smaller bolt breaking sooner if the slider takes a lateral force makes sense. but do you really want that to happen? i want my slider to stay on, even at the expense of the threads in the aluminum head. if the aluminum head threads get bunged up because the slider takes a hard hit, i can fix the aluminum threads. but i cannot readily fix the frame ground down by asphalt because the slider broke off.

i dunno, i'm still not totally convinced the 2-bolt system nets you much over the motovation 1-bolt system.
 

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I totally agree with ridesideways. I currently have Motovations installed on my bike. The only other slider I would use is the Moko/GSG but the cost is +$200 and is harder to get replacement parts.
 

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has anyone successfully installed a cycle cat frame slider for the 910R? If so, can you post instructions on how to?
 
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