Front sprocket cover fractured = no clutch
#31
As far as I am aware APE dont do a Sprocket Cover, well not going by my Price List. They do the Slave Support which is similar to the one Faster has made here.

www.hayabusazone.com/clutch.html

The PMR Cover is a nice bit of gear, would have to speak to the Manufacturer though on how affective the unit is as I havent heard any reports oneway or another.

www.pmrcomponents.com/pmrweb_013.html

The MPE cover is a true race component probably not required nor suitable for the street with its Outboard Bearing and I believe Custom Sprockets although the design may have changed by now.

Buy Australian and grab the Clutch Support off Faster.

Shayne

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#32
I'll look into those products. I like to buy Oz, and I will always use Busa board guys and FF1 has been excellent in quite a few areas, so I'm not having a go at him at all. From an engineering point of view, I think the bracket is just so so. Maybe, the original cover is also just so so and when given stronger springs, a few let go, and the bracket saves the day. But even with the bracket there's still a bit of flex. That doesn't mean things break, it just means we're dealing with an elastic material and if you don't exceed the limits, it's fine. Trouble with aluminium products, they don't react well to fatigue and drag racing adds the next level of cycling and stress. The flex doesn't come from the cylindrical part of the cover, it can only come from the thin flat surfaces, that's physics, and the biggest area that can flex is south of the bracket, and that's why I made my comments. The bracket only supports the north side. BUT, maybe that's enough!
I'd like to eliminate all the flex, not necessarily to stop it breaking (because even some standard ones don't break with stronger springs), but to get a better more definite clutch take up. It's a bit like the dogbones widely sold as offering standard plus 2' and 4' lowering. How many of these have been sold? But they don't actually do what they say they do. Standard height and they foul the lower fairing bracket. And so everyone ends up swapping dogbones or making individual ones. They don't mention the problems on the packet do they? So I made my own that can do standard, 2' and 4' all with undoing just the lower bolt and no problem with the bracket, and anyone can copy them for free. I'm a bit anal I guess, but I like things to do exactly what they say they do. I repeat, I'll buy Oz every time I can, even with stuff I can get OS, possibly a bit cheaper, and first stop is this site. <i></i>
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#33
I think Ian the main issue is the way in which the support itself is secured. Making the support from same thickness Stainless would be nice and potentially flex 1/3 that of ally. Just need to be mindfull that when structures are stiffened the stress tends to be transfered into another area where its more likely to be concertrated.

As the Suzuki rep mentioned having the bolts tightened is important..very important.

I havent heard of many cracked housings when using stock clutch springs... <i></i>
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#34
I think the general design is a bit piss poor. I'm sure the bolt dias are probably OK. But the spacing is fairly bad and with a flexible cover, I'd say most of the clutch load is already on only a couple of bolts. So a stiffer cover would reduce some bolt loads. Then add stiffer springs and you're probably still better off. Since not many complain about covers breaking with standard springs, except Chris who started the whole debate, the covers must be very close to failure anyway. Statistically a few will fail from fatigue, most won't. Stiffer springs and you slide down the curve and more failures. Add a bracket and maybe you're back to standard rates of failure.
But I'd still like a stiffer cover simply for the better feel. I've never had a bike that has such a spongy takeup. If you're going stiffer again, helicoil the bolt holes just to stop thread damage in the ally case and as a bit of insurance. I think 4 x 6mm bolts are fine for the sort of loads the clutch can generate.
What have I started here!!! Hope I haven't offended anyone, oh gosh oh golly....bugger! <i></i>
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