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[Riding Jezebel] Frame Sliders for the (2008) Ninja 250R
It seems that the world of frame slider manufacturers are all in agreement that this little bike is expensive to protect. While some other bike models have frame sliders available for under $50, Jezebel won't be getting protected for less than $100, and more likely closer to $200. I've talked about general frame slider design and selection (click), and now this post is dedicated to the research I've been doing for Jezebel, and what options are available specifically for a 2008 Ninja 250R. 

A little background on why I want sliders: I low-sided Jezebel going around 40km/hr by locking up my rear brakes on a curved road. After about a 4 ft. skid, I went down, with Jezebel sliding approximately 10ft along the pavement into on coming traffic. Her right fairing, front fairing, right turn signal and exhaust got all the damage. I'm pretty sure that if I had installed frame sliders the fairing at least would have been protected (though it's possible they would have still cracked from the stock turn signals that stick out - next on my list is flush mount lights!)

While frame sliders are originally designed to protect the frame and insides of the bike more than the pretty fairings (which are relatively cheap compared to what's inside the bike), the geometry of our bikes pretty much dictates that everything that's valuable is inside the triangle of the frame rail and where the suspension will hit the ground on a slide and we really don't have a GOOD frame point to mount to. Everything is relatively protected, that is, EXCEPT our fairings, which makes frame sliders for our '08+ 250s more like FAIRING SLIDERS. When deciding what frame slider to go for, you need to think about what you expect them to do for you. 

A NOTE ON MATERIALS: ANY frame slider puck that is not made of delrin or some other soft yet resilient plastic is pure street bling-bling crap, and will cause more damage in a real crash (other than a simple tip over) than not having sliders on in the first place. Aluminum ones are the ones that routinely catch on some piece of the pavement and flip the bike instead of snapping off altogether. Further, the carbon ones shatter, usually on initial contact, and carbon fiber weave, no matter what epoxy matrix it's in, HAS NO ABRASION RESISTANCE, so it just disintegrates (ever seen a modern F1 or Indy car even BUMP the wall, even at low speed? Shower of carbon fibers!)

Type one: Frame sliders that attach to dog ear brackets to the upper engine mount bolt. (Intuitive and other similar types)

Pros: Cheap to manufacture. Easy to install. Easy to understand and requires only basic hand tools to install. Takes little time to install. Will survive well for a simple tip over. True fairing/frame "No cut". Will protect fairings unless it slips/bends. Cons: Relatively weak dog ear brackets prone to bending, even in simple tip over. Tabs often bend and cause head/engine case damage in serious high/low side fall at speed. Often hard to keep the brackets aligned when torquing mount bolts. Extended pucks offer long leverage arm that often bends bracket even in moderate tip overs. Because of long arm and strong mount bolt, does not break off in catastrophic crash, causing more damage.  

Type two: Frame sliders that attach to bars that mount on the upper engine mount bolt and a lower point on the engine. (Sato)

Pros: Strong mounting point that will always be correctly positioned. Will survive well from simple tip over to moderate crash. Moderate relative installation difficulty. True fairing/frame "No cut". Shorter pucks that offer less of a leverage arm than type ones. More likely to break off in catastrophic crash, but because mounting brackets are often aluminum in this type, causes unfix-able tweaks and/or cracks to mount brackets/hardware/extenders. Cons: Mounts to points on mid engine case. Requires adapters and extended bolts/sleeves to mate to engine case. Has the potential to cause extensive engine case damage in a serious high/low side fall at speed.  

Type three: Frame sliders that attach to bars that mount on the upper engine mount bolt and a transmission/engine mount bolt. (Shogun)

Pros: Strong mounting point that will always be correctly positioned. Two point support on frame mount components. Creates a structurally reinforced crash bar that ONLY bears on the frame. Will survive (as has already been proven) a tip over to full on low/high side impact at speed. Shorter pucks that offer less of a leverage arm than type ones. Has been shown to break off when necessary, and easily repaired by re-bending mounting bracket on crash bar and replacing puck. Cons: Expensive to manufacture. Relatively difficult to install. Requires more support tools than type one or type two. Not a true NO CUT (requires that sprocket cover be notched to clear lower mount point) but fairing remains no cut (incidentally, taking some care with a dremel 60 grit sanding drum instead of cutting a chunk out of the cover will lead to a "factory" look to your install, and takes some care, but no more time to do correctly than proper careful cutting of the chunk as suggested. I used a total of 4 drum covers to do the entire notch with enough clearance to slide a playing card between the bar and the cover).  

Type Four: Replaces the upper engine mount dog ears with a HUGE piece of metal. (R&Gs)

By far, they require the most extensive disassembly of the bike, may only work on FI bikes due to possible interference issues (unconfirmed), and they're expensive, too. Although they look substantial, and surely would take some hard punishment, I would like to see how they survive a crash before making any more observations. I think that anything that would tweak the bracket enough to rip the slider but not total the bike would probably transmit back into the frame rail in a negative manner, possibly tweaking the frame in a manner that less substantial mounting methods would not. There is such a thing as "Too tough" when making a frame slider. (The one, twos, and threes are all old designs newly adapted to the new 250, and I based my observations on both the new 250 crashes as posted all over the web in pictures, previous incarnations of those mount types on other bikes and crash results, and some first hand experience).  

..So, what do you want your frame sliders to do?

Remember, you often get EXACTLY what you pay for. Sometimes less, rarely more. Type ones will surely protect your fairings under light impact, but little else. Type twos will also protect your fairings, but you may sacrifice your engine case in a moderate impact. Type threes have been shown to protect BOTH your engine and fairings even at moderate to high impacts and speed slides. ANYTHING that totals a type two, three or type four mount will total your bike. That said, I will be installing Shoguns on my bike. Using a floor jack, sockets, and a torque wrench they should take all of an hour to install from first fairing mount screw removal to last fairing bolt back installed and ready to ride. I'd prefer to damage my fairings before damaging my bike's insides, which would keep me off my wheels for longer. As a technical note, make sure that your engine mount bolts (upper and lower) that you replace and/or retorque are as free floating as you can get them on installation. A little binding is expected, and somewhat normal, but if you had to force them in and then torqued them with the weight of the engine on them, be aware that you MAY NOT have gotten proper torque on the bolt, ESPECIALLY with the Shogun kit. With the full weight of the engine assembly on the bolt before torquing, sometimes the bolt won't stretch properly, and subsequent road vibration and heat/cold cycles will allow the whole assembly to settle and equalize the load on the bolt. Re-torquing will often reveal that the nut will turn somewhat, indicating that it was not torqued properly initially. This is very common in the Shogun kit, as the replacement upper engine mount bolt is assembled from threaded rod that has a nut welded onto one end to form the 'bolt head'. The threaded rod is of a (sufficient) but lower grade than the factory bolt, and stretches more on initial torque. Oh, and you might want to put a spot of black paint on the thing, too, to prevent corrosion, if you're given to care about things like that. About 6 inches of the bolt is exposed at the front of the engine case, and will get all of the road water and dirt on it that your front tire kicks up. Touch up black on the bolt head and nut will ensure that you won't have to worry much about rusted tight components should you ever need to remove them later in life. At the end of the day, no matter what you choose (unless you're putting them on for pure cosmetics), it's an insurance policy in the form of a hard part. Like all insurance policies, the best ones are the ones that you NEVER have to test firsthand! Credit: Info comes from Ninjette Wiki

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