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Discussion Starter · #1 ·
RP23 in non-propedal mode

Took the ML2 out for a ride this afternoon. I had RP23 in the propedal mode and set at #2. Half-way through the ride I flicked the pro-pedal off and I noticed a big difference in the feel of the bike. It felt sluggish. I looked down at the linkage and noticed it was moving and the movement was being caused by my pedaling. I would stop pedaling and coast and the movement would subside. I flicked it back in the propedal mode, looked down and there was no movement in the linkage when I was pedaling the bike. I tried this a few times going back and forth. It seems in the non-propedal mode there is some noticeable pedal induced bobbing. I did not experience this with my old ML with the RP3. Has anyone else experienced this effect? I was really surprised at the amount of bob.
 

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Well non-propedal mode is fully active. Wouldn't you expect it to bob a lot? The rp3 didn't have an "off" mode like the rp23, but instead had 3 varying levels of propedal. On my racer-x, it's a similar situation. I ride in #1, and with it on always. If I flip it over to off, it's super active. A bit too active in my opinion for horst link design but what can ya do. Works great with propedal mode so that's all that really matters.
 

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Discussion Starter · #3 · (Edited)
notenoughtime said:
Well non-propedal mode is fully active. Wouldn't you expect it to bob a lot? The rp3 didn't have an "off" mode like the rp23, but instead had 3 varying levels of propedal. On my racer-x, it's a similar situation. I ride in #1, and with it on always. If I flip it over to off, it's super active. A bit too active in my opinion for horst link design but what can ya do. Works great with propedal mode so that's all that really matters.
Actually no I do not expect it to bob alot. I would expect minimal pedal induced bobbing. I expect the rear shock to respond to the terrain and not to my pedaling. I have had several Racer Xs and MLs and I never experienced this level of pedal induced bobbing.
 

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I've noticed that the rear is a lot more active w/PP off. But have never experience bobbing as a result of pedaling while JRA. I have noticed some bob while grinding hard during tough climbs though.

later,
simp
 

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While just pedaling normally I would not notice the bob with propedal off on my RP23. Even with the DHXa there is very little bob. Now, if I mash, it's a whole other story. How much do you weigh and what's your pressure?
 

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Discussion Starter · #6 ·
mcgrath said:
While just pedaling normally I would not notice the bob with propedal off on my RP23. Even with the DHXa there is very little bob. Now, if I mash, it's a whole other story. How much do you weigh and what's your pressure?
I weigh 200lbs and the RP3 is set at 160 PSI. I will be playing around with the pressure. I actually noticed the bob while I was on flat terrain.
 

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JTBAZ said:
I weigh 200lbs and the RP3 is set at 160 PSI. I will be playing around with the pressure. I actually noticed the bob while I was on flat terrain.
yeah, don't worry about it. it is not pedal bob. it is weight transfer bob. think of it as kinda like the inverse of brake dive.

the RP23 has very very low compresion damping (when "off") so that is what you get to have super smooth performance. To get rid of that.... (if it bothers you), you can do 1 of 2 things.
1. increase compression damping.
2. use the chain torq to create anti-squat.

but just an FYI, anti-squat = real pedal bob.
 

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demo_slug said:
yeah, don't worry about it. it is not pedal bob. it is weight transfer bob. think of it as kinda like the inverse of brake dive.
Good to see someone finally explain it this way and clarify what is really happening isn't because of pedaling. We just need to smooth out our pedal stroke :)
 

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demo_slug said:
yeah, don't worry about it. it is not pedal bob. it is weight transfer bob. think of it as kinda like the inverse of brake dive.

the RP23 has very very low compresion damping (when "off") so that is what you get to have super smooth performance. To get rid of that.... (if it bothers you), you can do 1 of 2 things.
1. increase compression damping.
2. use the chain torq to create anti-squat.

but just an FYI, anti-squat = real pedal bob.
Nicely put, Demo...

Option 3 - Pedal in smooth circles, low gear and high rpm's, so you avoid harsh weight transfers.

Any bike pedaled smoothly on the saddle, will shoot itself forwards.

Many people don't like it, though as it requires you to pay more attention to weight transfer on the bike (pedaling over the saddle straddle, or the nose, for example) and it quite doesn't work for low traction surfaces as you may spin the tyre very easily.

If you're a pedal masher, then you need aid by adding compression or with chain torque. Off the two options, chain torque should be your very last resort (as a designer) as it more likely lock your suspension and limit traction anyway.
 

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I'd check your pressure and sag. I run the RP23 on my ML with PP off pretty much all the time. I think it feels great. When I sit and pedal there is minimal shock movement. If I stand on it and climb I'll get some bob but that's expected. I run about 180 psi and I weigh 150 lbs. which gives me a little less than 1/2" sag. Sometimes my shock loses air and then I do notice that it bobs more. I also noticed that it bottoms out a good bit on the bigger rocks and drops and stuff.
 

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Discussion Starter · #11 ·
Warp said:
Nicely put, Demo...

Option 3 - Pedal in smooth circles, low gear and high rpm's, so you avoid harsh weight transfers.

Any bike pedaled smoothly on the saddle, will shoot itself forwards.

Many people don't like it, though as it requires you to pay more attention to weight transfer on the bike (pedaling over the saddle straddle, or the nose, for example) and it quite doesn't work for low traction surfaces as you may spin the tyre very easily.

If you're a pedal masher, then you need aid by adding compression or with chain torque. Off the two options, chain torque should be your very last resort (as a designer) as it more likely lock your suspension and limit traction anyway.
OK - This just confirms what I always suspected - I am just a lousy rider who can't pedal.
 

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Discussion Starter · #12 ·
demo_slug said:
yeah, don't worry about it. it is not pedal bob. it is weight transfer bob. think of it as kinda like the inverse of brake dive.

the RP23 has very very low compresion damping (when "off") so that is what you get to have super smooth performance. To get rid of that.... (if it bothers you), you can do 1 of 2 things.
1. increase compression damping.
2. use the chain torq to create anti-squat.

but just an FYI, anti-squat = real pedal bob.
In regards to 1 - Does that mean more pressure in the shock or is there a knob I am not aware of on the RP23?
 

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Discussion Starter · #13 ·
woodyak said:
I'd check your pressure and sag. I run the RP23 on my ML with PP off pretty much all the time. I think it feels great. When I sit and pedal there is minimal shock movement. If I stand on it and climb I'll get some bob but that's expected. I run about 180 psi and I weigh 150 lbs. which gives me a little less than 1/2" sag. Sometimes my shock loses air and then I do notice that it bobs more. I also noticed that it bottoms out a good bit on the bigger rocks and drops and stuff.
I am going to increase the pressure - hopefully that will help.
 

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woodyak said:
I'd check your pressure and sag. I run the RP23 on my ML with PP off pretty much all the time. I think it feels great. When I sit and pedal there is minimal shock movement. If I stand on it and climb I'll get some bob but that's expected. I run about 180 psi and I weigh 150 lbs. which gives me a little less than 1/2" sag. Sometimes my shock loses air and then I do notice that it bobs more. I also noticed that it bottoms out a good bit on the bigger rocks and drops and stuff.
180?? Dang, isn't that too much!!
As far as I understand the RP23 shares the canister with the RP/Float Series shocks, so our pressures shouldn't be that far.

Are you running a tall fork like I do?

Aren't you using a higher volume sleeve?

I'm not far from you in weight - around 145 unloaded, 150-155 fully loaded - and the leverage of my SB is fairly similar to your ML (2.5:1)... and I'm on 26% sag (around 13-14mm) at 135 PSI, which seems to be the magical number for me.

Not criticizing, bro... just comparing notes. ;)
 

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JTBAZ said:
I am going to increase the pressure - hopefully that will help.
Yes it will... 5 PSI made a real difference for me. Going from 130PSI to 135PSI put me into Pedaling Wonderland.

Start increasing by 5 PSI until it feels nice and plush. Stop where you feel the fork dives too much and back it off 5 PSI. That's the point where you have the suspension "balanced".
 

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Warp said:
180?? Dang, isn't that too much!!
As far as I understand the RP23 shares the canister with the RP/Float Series shocks, so our pressures shouldn't be that far.

Are you running a tall fork like I do?

Aren't you using a higher volume sleeve?

I'm not far from you in weight - around 145 unloaded, 150-155 fully loaded - and the leverage of my SB is fairly similar to your ML (2.5:1)... and I'm on 26% sag (around 13-14mm) at 135 PSI, which seems to be the magical number for me.

Not criticizing, bro... just comparing notes. ;)
My measurements are similar to yours: 150lbs unloaded, appx 160lbs loaded. I run my RP23 at 135-140psi with appx 25% sag.

I was also shocked to see the previous poster's claim of 180psi. The Fox on my NRS needs a PSI equal to your body weight, so I run my NRS a litle higher at 155psi. When I first got my ML I put the same psi in the RP23 and it was WAY too stiff. @180psi I bet I could barely budge the rear end!

Thx...Doug
 

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That's odd. I weigh 180 and keep the pressure at 100 for 25% sag. Never comes close to bottoming out on my rx100. I have the RP3 and keep the Propedal at 2 and don't feel bob unless I stand and hammer. How can my pressure be so much lower than most others here? Maybe each shock is different?
 

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Yeah...I'm with you guys. I weigh 180lbs and have a Push RP23. I run 120psi and have about 20% sag. I never bottom the shock and I ride in setting 1 with ProP on. What gives with the different pressures???? Does the Push rebuild make the shock more "stiction" free or something??? :confused:
 
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