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Old 05-31-2010, 04:13 PM   #1
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Default MRX4 Second Gear Engagement

Is there anyway to verify that the MRX4 is shifting into second gear at the right time, other than doing a drag race and listening for a change in pitch? It seems like I have to be going ridiculously fast before it shifts into 2nd.

I heard it shift once when flooring it on a long straight away, but even when going fast up and down my residential street, I don't think I hear it engage.

The manual is a little vague, but it seems like I should check some nut and spring compressions with calipers??
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Old 05-31-2010, 04:41 PM   #2
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If you can't notice the shift, it is either shifting WAY too early or not at all. Top speed and rpms are the indicator. If the motor is just screaming on the straight but not going very fast, it's not shifting. Loosen the two bolts with the springs a bit. If it's fast but takes a bit of space to really get the rpms up, it's shifting really early. Tighten the same screws.
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Old 05-31-2010, 04:43 PM   #3
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engine neds to be tuned spot on before you start adjusting the 2 speed,
when you backout both clutch screws you will shift sooner and tighten to shift later,but only small adjustments at a time assuming your shoes are in good shape.
how you want it to shift depends on size of racing area and gearing.
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Old 05-31-2010, 09:52 PM   #4
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Its really screaming fast, so its probably shifting at about the right time then. It seems pretty quick off the line too. I think the main thing is that I don't know what to listen for. Maybe some YouTube videos will help. I should play with the screws and get a feel for the tuning.
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Old 06-02-2010, 07:33 PM   #5
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A quarter of a turn is a large change on the screws when you are close to the right setting.
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Old 06-03-2010, 06:21 AM   #6
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what gears are you running? Sometimes if you are running a close tooth spread, you wont hear the gear change.
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