i just purchased and installed a clutch kit for my 07 apex. i love the mid range pull of it, but it engages at a way high rpm. i expected maybe a 500 rpm jump but now it engages around 5000 rpm. it does have a little over rev on top at 11,000 and then backs off to 10,600. my question is how to lower engagement rpms alittle while keeping my top end rpm?
Len Todd
TY 4 Stroke God
Well you are over reving at top end. Peak is 10,250 with 10,500 pushing it. So I would start by adding weight to the tip on the primary's weights. As you bring down the top end, the enagement MAY come down enough to satisfy you. If not, you could add some weight to the heel, but then you may have to lighten the tip again.
What Primary Spring do you have in there? Larger engagement adjustments can be made by changing the Primary Spring. Probably OSO. Right? The OSO was just too high of engagement for me.
What Primary Spring do you have in there? Larger engagement adjustments can be made by changing the Primary Spring. Probably OSO. Right? The OSO was just too high of engagement for me.
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Peak HP for an Apex (it says 07 Apex) is 10,500 to 10,800 rpm. To lower your engagement you need to go to a lower initial force spring.
Len Todd
TY 4 Stroke God
The target is in fact 10,500, if it is a fuelie. I checked the Tech Manual which addresses both Carbed & Fuelie. I erroneously assumed carbed, which is 10,250. Allen apparently knew that '07s are only Fuelies. I checked the parts catalog to verify this. You learn something new every day. 
However with a target of 10,500, 11,000 at mid-shift seems a bit too high. So assuming all the parts are clean and in spec, what is he going to do to lower the RPM, unless there is weight added? Add weight to the mid-point to get rid of the 11,000.
I guess, I would get the right spring for the engagement desired, like Allen suggested. Then adjust weight, if needed, from there. But be aware that changing the primary spring may raise other undesired affects (e.g. changing RPMs, etc.) A kit usually comes with matched parts.
However with a target of 10,500, 11,000 at mid-shift seems a bit too high. So assuming all the parts are clean and in spec, what is he going to do to lower the RPM, unless there is weight added? Add weight to the mid-point to get rid of the 11,000.
I guess, I would get the right spring for the engagement desired, like Allen suggested. Then adjust weight, if needed, from there. But be aware that changing the primary spring may raise other undesired affects (e.g. changing RPMs, etc.) A kit usually comes with matched parts.
