Compression braking effects - how to decrease/increase?

Joko
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Joko
Edited Date/Time 11/18/2018 3:55am
Is the engines primary compression ratio the only variable determining the amount of rear wheel compression braking in each gear? If a bike has too much braking effect, what can be done to reduce it? Rekluse clutch help? Which current 450's have less compared to other brands? I ask because ilike less of the braking effect on sand tracks vs hardpack. Thanks...
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kb228
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kb228 11/17/2018 1:38pm
11/17/2018 1:38pm
I have a rekluse zstart pro auto clutch in my 450 and there is no engine braking. Id imagine you can adjust the amount by feathering the clutch...
Ebs
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Ebs 11/17/2018 1:46pm
11/17/2018 1:46pm
slipper clutch
Helda
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Helda 11/17/2018 1:54pm
11/17/2018 1:54pm
Go up a gear for less and down a gear for more....
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Joko
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Joko 11/17/2018 3:49pm
11/17/2018 3:49pm
2019 COMPRESSION ratios
CRF450 13.5:1
YZF450 12.8
KTM/HUS 12.75
KX 12.5
RMZ 12.5

One shootout (Keefer?) said the Honda had the least engine braking? Is it something to do with connecting rod length or stroke that gives the Honda less engine braking?

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colintrax
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colintrax 11/17/2018 3:57pm
11/17/2018 3:57pm Edited Date/Time 11/17/2018 3:59pm
The running compression ratio is different than the theoretical compression ratio.
Also things like spark advance, fuel mixture, rear suspension design, and gear ratio will affect engine braking.
Johnny Depp
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Johnny Depp 11/17/2018 4:06pm
11/17/2018 4:06pm
If you dial up your idle you will have less compression braking. Mapping for FI can accomplish this.
MediumRare 11/17/2018 7:09pm
11/17/2018 7:09pm
Use the compression braking modulating lever. Comes free on most bikes.
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bama205
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bama205 11/17/2018 9:36pm
11/17/2018 9:36pm
Buy a yz250
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CarlinoJoeVideo
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CarlinoJoeVideo 11/18/2018 12:46am
11/18/2018 12:46am
Engine braking can be adjusted with mapping these days. I’ve ridden some very impressive maps from Twisted Development that completely changed my suspension charactistics because how it frees up the tension in the chassis. It’s very interesting!
Derek Harris 11/18/2018 3:54am
11/18/2018 3:54am Edited Date/Time 11/18/2018 3:55am
Alterinf ignition timing off throttle is largely effective at higher rpms in the map


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