motorcycle amp with too much bass

I recently picked up a Shark audio system for my bike. It is the 600watt system (true output is only 75w x 2 @ 4ohm). The setup came with 2 small speakers. My problem is that there is way too much bass output from the amp and I don't have any type of EQ adjustment. So within the first week I ended up blowing one of the speakers. I replaced the speaker with a Polk 3.5" hoping the Polk would be able to handle the bass, but its even too much for that speaker. Then I tried putting a bass blocker in to see if that would help, but it barely did anything. Whenever I try to turn it up, it cracks and sounds like complete garbage.

I need some help finding a solution. Since it is on a bike, space is limited so unless there is a very tiny crossover, I don't think I'll be able to go that route...

Please help.

Edit: The capacitor is a 200uF 50v which I believe should be around a 200MHz cut-off...

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Kenny
Owner / Technician
KKD Garage LLC
Albany, NY 12205

I tried a different capacitor that was rated for 3000hz at 4 ohms and that seems to have worked a lot better. I may have to play around a bit to get it just right (not enough lows right now). But I may end up leaving it until I can get a front fairing with radio.

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Kenny
Owner / Technician
KKD Garage LLC
Albany, NY 12205