Rear shock question

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ebike11   1 MW

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Rear shock question

Post by ebike11 » Apr 26 2021 7:41am

Hi guys
I just got a DNM burner rear shock with 2 different knobs for adjustment. My other stock shock had no adjustments
Which direction should I set each knob to in order to get the stiffest and least amount of spring bounce??

Compression knob
+ = pressure increase
- = pressure decrease

Rebound knob
+ = damper increase (slow)
- = damper decrease (fast)

Thanks!!

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dogman dan   100 GW

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Re: Rear shock question

Post by dogman dan » Apr 26 2021 8:15am

Try increasing damper some first. If that doesn't tame it, then some more stiffness. But don't stiffen it too much, just what you need for your weight. Personally, I'd rather pedal bounce mildly, than put my lower back through too stiff a shock. But for sure, stiffen up till you don't bottom out anymore if you do some bunny hops.

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MadRhino   100 GW

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Re: Rear shock question

Post by MadRhino » Apr 26 2021 10:18am

Compression need to be set to sag 40% with rider on the bike. This means that an 8 inch travel suspension has to go down about 3 inches when you are in riding position on the bike with all the equipment and luggage that you will be riding with.

Rebound control need to keep the wheel on the ground when you ride on bumps. With a hub motor, usual shock dampers don’t have enough setting range to tame the weight of the wheel. So you will have to set it to the slowest and start from there. Then drop a sand bag on the street and ride on it at the average speed that you will be riding, to see if the rear wheel does absorb the hit without bouncing off the ground after passing it. It will probably do, so you just leave the setting at the slowest and know the damper valve does not close tight enough. If it does pass it smooth, then you can drop a 2nd sand bag 4 ft away from the first and try opening the valve by small increments and ride on both bags until you can pass them both without bouncing off the ground.

That is pretty much the best that you can achieve, but if you succeed you can try setting the bags closer to one another. The fastest you ride, the more difficult it will be to tune that simple test. Even at moderate speed you might need to drop tire PSI to keep it on the ground.

Then you will know the limits of your suspension, and from which speed you need to stand on the pedals to absorb bumps.
Make it fool-proof, and I will make a better fool.

ebike11   1 MW

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Re: Rear shock question

Post by ebike11 » Apr 26 2021 3:41pm

dogman dan wrote:
Apr 26 2021 8:15am
Try increasing damper some first. If that doesn't tame it, then some more stiffness. But don't stiffen it too much, just what you need for your weight. Personally, I'd rather pedal bounce mildly, than put my lower back through too stiff a shock. But for sure, stiffen up till you don't bottom out anymore if you do some bunny hops.
Ok. Ill start by turning the damper knox all the way to the slowest position
What should i set the compression knob at?
Im trying to acheive max. stiffness and work from there.
Thanks

ebike11   1 MW

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Re: Rear shock question

Post by ebike11 » Apr 26 2021 3:48pm

MadRhino wrote:
Apr 26 2021 10:18am
Compression need to be set to sag 40% with rider on the bike. This means that an 8 inch travel suspension has to go down about 3 inches when you are in riding position on the bike with all the equipment and luggage that you will be riding with.

Rebound control need to keep the wheel on the ground when you ride on bumps. With a hub motor, usual shock dampers don’t have enough setting range to tame the weight of the wheel. So you will have to set it to the slowest and start from there. Then drop a sand bag on the street and ride on it at the average speed that you will be riding, to see if the rear wheel does absorb the hit without bouncing off the ground after passing it. It will probably do, so you just leave the setting at the slowest and know the damper valve does not close tight enough. If it does pass it smooth, then you can drop a 2nd sand bag 4 ft away from the first and try opening the valve by small increments and ride on both bags until you can pass them both without bouncing off the ground.

That is pretty much the best that you can achieve, but if you succeed you can try setting the bags closer to one another. The fastest you ride, the more difficult it will be to tune that simple test. Even at moderate speed you might need to drop tire PSI to keep it on the ground.

Then you will know the limits of your suspension, and from which speed you need to stand on the pedals to absorb bumps.
Thanks for your reply again!!
I usually only do street riding so the worst part are potholes and rough roads. No offroading.
At the moment im trying to prevent my rear post rack with 10+ pounds of weight from rubbing on the rear wheel during bumps. Its happened a bunch of times.
My comfort comes second haha

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