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I noticed the rolling resistance on my Heckler MX was really dragging. However I was surprised to find that the PSI was in the high 30s. I ended up filling the tires up the rated 50 PSI and the difference was night and day.

The upside
Rolling resistance improved noticeably: I was mainly staying in the highest gear whereas before I would typically default to the second highest gear. The minion DH2s and DHRs are way less draggy than I thought

The downside
Going down the same dirt and grass hills I'd gone down before, I noticed the tires felt more "slippery". I even had to catch the bike as it started to slip.

I know from car racing that PSI can make a difference however being a bike newbie, I never expected anything so dramatic just by adjusting PSI. I bought Dissectors to improve rolling resistance. Maybe now I'll wait to install them.
1946061
 

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Ummmm are you actually on single track trails? High 30s sounds way to high unless your on gravel or roads.......

I wouldnt measure being in higher gear all the time as being in the "right" or "good" gear. Also are you tubeless?

I am not on an E bike but I literally run 16 psi on my 2.6x 35mm rim 29er and about 22 psi on my 2.4x 30mm rim 27.5.
 

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The downside
You haven't been around long enough to know another downside of sharing something like this is how open you leave yourself to horrible judgment from certain members on the site. Thankfully none of them have shown up yet, but you've put the chum in the water, so look out.

Back in the 90s, on 1.95 and 2.0 tires, 35 psi wasn't unheard of, but over time people figured out lower pressures work better for many reasons.

I don't know what sort of gauge you're using, but it may be way far off. A quality gauge will be more accurate. I set pressures before every ride.
 

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I second the quality gauge. Buy a good one, figure out your preferred PSI, and then guard the gauge with your life and use it before every ride. Keep in mind that different gauges will provide different readings, so always use the same one.
 

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high pivot witchcraft
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I am not a circling shark attracted by the chum, but I will say that running even soft rubber compound tires at those kinds of pressures will significantly impact traction (on the downs and climbing), and not in a good way, and will likely impact suspension performance (throwing some more chum out there for those to tell me I shouldn’t be relying on lower tire pressures for suspension performance and that I don’t know how to set up my suspension 😝).
 

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I sure hope they are not tubeless, this will not end well.
The thing is, what most people do not understand is at lower pressure tubeless tires have way less friction because the tire and the tube are not rubbing together as the tire compresses on the ground. but year high 30psi sounds like if he was tubeless they would blow the tires off the rim.
 

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I am not a circling shark attracted by the chum, but I will say that running even soft rubber compound tires at those kinds of pressures will significantly impact traction (on the downs and climbing), and not in a good way, and will likely impact suspension performance (throwing some more chum out there for those to tell me I shouldn't be relying on lower tire pressures for suspension performance and that I don't know how to set up my suspension ?).
Ehlower pressure is the start of a good suspension set up. My guess is most people who think you need 35psi and then you just tune your suspension do not understand bike dynamics.
 

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Discussion Starter · #9 · (Edited)
Thanks for the replies. I am not a proponent of high or low pressures just making an observation.

That said, I am going to lower the pressures before my next ride. I believe the tires are tubeless. They are the stock setup that came on my Heckler MX-S.

I just saw 50 PSI on the tire and figured that was the correct pressure. I guess I‘m lucky I didn’t wind up with sealant everywhere. I am not sure why 50 PSI would be posted clearly on a tire that should be set far lower. Again, I appreciate the insights. Having a tire blow on the trail would’ve been most unfortunate not to mention unpleasant.
 

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Thanks for the replies. I am not a proponent of high or low pressures just making an observation.

That said I am going to lower the pressures before my next ride. The tires are tubeless. I just saw 50 PSI on the tire and figured that was the correct pressure. I guess I m lucking I didn't wind up with sealant everywhere. Again, I appreciate the insights
Lucky you did not crack the rim sidewalls, have witnessed that a few times. The PSI on the tire is the max the tire can hold but that does not mean the rim can hold that much. Most tubeless rims max is 35-38 psi or thereabouts.
 

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high pivot witchcraft
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Thanks for the replies. I am not a proponent of high or low pressures just making an observation.

That said I am going to lower the pressures before my next ride. The tires are tubeless. I just saw 50 PSI on the tire and figured that was the correct pressure. I guess I m lucking I didn't wind up with sealant everywhere. Again, I appreciate the insights
I thought I had seen a few RR-related threads on here disputing the theory that increased pressure = decreased RR/increased speed. Or at least suggesting that it doesn't make that much of a difference. Maybe I am wrong on that.
 

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Cycologist
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If that's how you ride, you may like less aggressive tires than the Dissectors. But yes, with less aggressive and/or with high pressure, you're going to have less traction, meaning you'll have to take it slower when cornering. But yeah, 50psi is way high.
 

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I thought I had seen a few RR-related threads on here disputing the theory that increased pressure = decreased RR/increased speed. Or at least suggesting that it doesn't make that much of a difference. Maybe I am wrong on that.
on bumpy ground it is true that really high pressure while they can feel faster because of the way the tire bounces are not actually faster when measured by equipment.

pro Enduro and XC rider typically ride between 17 to 24 psi depending on their weight set up and terrain.
 

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I thought I had seen a few RR-related threads on here disputing the theory that increased pressure = decreased RR/increased speed. Or at least suggesting that it doesn't make that much of a difference. Maybe I am wrong on that.
I believe part of it is just feel, higher pressure feels faster because you feel every imperfection in the riding surface.
 

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OP - this will get you in the ballpark: SRAM | AXS

The manufacturers max pressure on the sidewall is meaningless and possibly dangerous. I recall having some Vredestein road tires that had max pressure listed somewhere around 140 psi. Yikes. Sure, the tire max might be 50, but that doesn't mean that the bead won't blow off the rim if tubeless (really bad) or that the rim might not crack (really bad).
 

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Discussion Starter · #20 ·
I believe part of it is just feel, higher pressure feels faster because you feel every imperfection in the riding surface.
I can say that increasing PSI significantly decreases rolling resistance. Faster is relative depending on whether your momentum is due to gravity or pedaling. As I mentioned the higher pressure was like a difference in gears. The highest gear with high pressure became as easy to pedal as the second highest with lower pressure.

Regardless, handling suffered significantly with such high pressure so I am going back to low 30s PSI. Thankfully, from the feedback on this board, I have averted the tires blowing out.
 
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