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Slow rolling hubs what to do

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Slow rolling hubs what to do
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flag rickyvic
Posted: Mar 19, 2019 at 9:15 Quote
I own an enduro bike which is not the best climber, I know, although listen to this.
I fell in love with a friend's bike and now I have it (a GT sanction), very happy with it although the difference between the two is how fast they roll in not so steep uphill, even tarmac.

So the older bike uses shimano slx hubs, the new one dt swiss 350.
Open vs sealed bearings.
Well the difference is massive slx hubs on some old heavy rims roll massively better (under weight) compared to the dtswiss 350 with shiny ex511 rims.
I thoght it was a matter of tyres so I tried the same tyres.
Nothing still huge difference, although they seem closer on very steep uphill cycling.

I am wondering if I can get closer to that shimano open bearings or not.

One note: all this with nearly no maintenance my friend has very little knowledge of this stuff, while my bearings are well greased and mint.

Question: what to do to get the sealed bearings close to open ones. I heard skf are a good choice.
flag skerby
Posted: Mar 19, 2019 at 10:09 Quote
Just remove the seals from the bearings, they pop right out, they will roll imperceptibly faster. Next, remove the seal from the freehub (will only make it coast faster).

This will make only a very small difference and you will probably destroy your hub the first muddy ride. If your bike is really that much slower with the DTs, a very high quality hub, either the hub is messed up or you have some other problem, like your brake is rubbing really bad with that wheel.
flag R-M-R
Posted: Mar 19, 2019 at 10:35 Quote
skerby is correct.

Remove the wheels and turn the bearings or the axle in your fingers. If the bearings are anything other than completely seized, the power loss due to your hub bearings is imperceptible while riding. For you to notice a "massive" difference while riding, the hubs would have to be causing maybe 10 watts of drag per bearing while pedaling on flat ground. This is enough that the hub should feel warm. On a long, fast descent - ex. down a big hill on a roadway - the hubs could be consuming 40 watts per bearing, which would make the hubs hot like an incandescent light bulb. I feel pretty certain this isn't the case.

So, the good news is that you don't have to buy new wheels; the bad news is that something else is wrong.
flag zsandstrom
O+
Posted: Mar 19, 2019 at 14:04 Quote
So, at the risk of being pesky, at you SURE it's the bearings? It's far more likely that it's a shitty bottom bracket, tubeless vs tubed, a dragging brake rotor, or you're enormously over-tightening your axles.
flag englertracing
O+
Posted: Mar 19, 2019 at 14:56 Quote
rickyvic wrote:
I own an enduro bike which is not the best climber, I know, although listen to this.
I fell in love with a friend's bike and now I have it (a GT sanction), very happy with it although the difference between the two is how fast they roll in not so steep uphill, even tarmac.

So the older bike uses shimano slx hubs, the new one dt swiss 350.
Open vs sealed bearings.
Well the difference is massive slx hubs on some old heavy rims roll massively better (under weight) compared to the dtswiss 350 with shiny ex511 rims.
I thoght it was a matter of tyres so I tried the same tyres.
Nothing still huge difference, although they seem closer on very steep uphill cycling.

I am wondering if I can get closer to that shimano open bearings or not.

One note: all this with nearly no maintenance my friend has very little knowledge of this stuff, while my bearings are well greased and mint.

Question: what to do to get the sealed bearings close to open ones. I heard skf are a good choice.

Well greased?
Please explain.
Truck wheel bearing grease?
Marine boat trailer grease?
Lying to you about being bike specific grease?

Greases to use
Skf lesa 2
Kluber isoflex lds18 spec a - what onyx uses.
Ceramic speed all around grease which i expect is one of the former.

Both greases are low temp greases with low viscosity oil.

You want a low percentage of fill for 25% for speed, up to 75% for water resistance.

Which is what we need in our low load low rpm low temperature besrings.

Second is seals you want llb besrings with non contact seals.

Also enduro are trash chineese bearings, you want high quality NTN japaneese bearings.
Some dork stuff here
https://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=150132&sid=3b12370d4eb64edf93c27145d89812fa

Next,
Stop with the grease on the ratchet system get all that shit out of there
NEVER EVER,
order some hadley oil for 5 bucks, or some dumonde tech lube, hadley preferred.

Make sure you check for bent rotors as well.
flag rickyvic
Posted: Mar 19, 2019 at 15:06 Quote
R-M-R wrote:
skerby is correct.

Remove the wheels and turn the bearings or the axle in your fingers. If the bearings are anything other than completely seized, the power loss due to your hub bearings is imperceptible while riding. For you to notice a "massive" difference while riding, the hubs would have to be causing maybe 10 watts of drag per bearing while pedaling on flat ground. This is enough that the hub should feel warm. On a long, fast descent - ex. down a big hill on a roadway - the hubs could be consuming 40 watts per bearing, which would make the hubs hot like an incandescent light bulb. I feel pretty certain this isn't the case.

So, the good news is that you don't have to buy new wheels; the bad news is that something else is wrong.

Thank you guys.
A few notes:
bearings are perfect run smooth, so I guess you are right.
I checked the bearings and serviced them, nothing.
I serviced the bb
I will check if the rear axle is overtightened
Brakes dont rub (funny in the shimano hubs bike they rub pretty badly)

The slx hubs run a lot faster than any other bike, clearly maybe they have some very high end balls I dont know

I noticed the dt 240s run well too looking at my friends, at high speed my bike runs very fast and faster than most people (another odd thing) meaning that this is a problem found at very low speed and under load.
flag rickyvic
Posted: Mar 19, 2019 at 15:15 Quote
englertracing wrote:
rickyvic wrote:
I own an enduro bike which is not the best climber, I know, although listen to this.
I fell in love with a friend's bike and now I have it (a GT sanction), very happy with it although the difference between the two is how fast they roll in not so steep uphill, even tarmac.

So the older bike uses shimano slx hubs, the new one dt swiss 350.
Open vs sealed bearings.
Well the difference is massive slx hubs on some old heavy rims roll massively better (under weight) compared to the dtswiss 350 with shiny ex511 rims.
I thoght it was a matter of tyres so I tried the same tyres.
Nothing still huge difference, although they seem closer on very steep uphill cycling.

I am wondering if I can get closer to that shimano open bearings or not.

One note: all this with nearly no maintenance my friend has very little knowledge of this stuff, while my bearings are well greased and mint.

Question: what to do to get the sealed bearings close to open ones. I heard skf are a good choice.

Well greased?
Please explain.
Truck wheel bearing grease?
Marine boat trailer grease?
Lying to you about being bike specific grease?

Greases to use
Skf lesa 2
Kluber isoflex lds18 spec a - what onyx uses.
Ceramic speed all around grease which i expect is one of the former.

Both greases are low temp greases with low viscosity oil.

You want a low percentage of fill for 25% for speed, up to 75% for water resistance.

Which is what we need in our low load low rpm low temperature besrings.

Second is seals you want llb besrings with non contact seals.

Also enduro are trash chineese bearings, you want high quality NTN japaneese bearings.
Some dork stuff here
https://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=150132&sid=3b12370d4eb64edf93c27145d89812fa

Next,
Stop with the grease on the ratchet system get all that shit out of there
NEVER EVER,
order some hadley oil for 5 bucks, or some dumonde tech lube, hadley preferred.

Make sure you check for bent rotors as well.


As far as grease is concerned I use specific dt swiss grease, admittedly it is packed wih grease but now we tried a lighter grease, the mechanic did but I am not sure is really understanding what he is doing, so that might be it the type of grease is still not the right one.

On the ratchet, that needs to be lubed, dt says otherwise you risk that it fails.

Not sure if that is the problem or maybe it is just that the comparison with open bearings is unfair?
flag englertracing
O+
Posted: Mar 19, 2019 at 17:50 Quote
If you re read my post carefully,
I mention bearing grease and fill quantaties
Then i mention oil for the ratchet system,
The type hadley uses.
Did thoulsanss of miles with hadley in the dt swiss 36t ratchet, its appearance never changed.
flag R-M-R
Posted: Mar 19, 2019 at 19:12 Quote
rickyvic wrote:
Thank you guys.
A few notes:
bearings are perfect run smooth, so I guess you are right.
I checked the bearings and serviced them, nothing.
I serviced the bb
I will check if the rear axle is overtightened
Brakes dont rub (funny in the shimano hubs bike they rub pretty badly)

The slx hubs run a lot faster than any other bike, clearly maybe they have some very high end balls I dont know

I noticed the dt 240s run well too looking at my friends, at high speed my bike runs very fast and faster than most people (another odd thing) meaning that this is a problem found at very low speed and under load.

Yes, Shimano hubs - when adjusted properly - are usually a little faster than cartridge bearing hubs, but we're talking less than 1% of your total power output.

It's not the bearings. Not the hub's driver mechanism. Probably not the BB, as even the worst BB shouldn't waste more than 10 or 15 watts and it will quickly wear itself to the point of play in the bearings, so you'll know it was the BB within a ride or two.

When you say you tried the same tires, are they definitely the same tires? For example, the ubiquitous Minions are available with everything from light and fast casings to DH double-ply casings. If you compared DH Minions to EXO Minions, that's your answer right there. Just want to eliminate the easy things first.

Could it be the bike? Maybe one bike has squishy pedaling kinematics and the other is much more efficient, or one bike has a more efficient riding position. For me, a bike with low anti-squat and a slack seat tube angle reduces my climbing pace considerably and it feels even worse.
flag rickyvic
Posted: Mar 20, 2019 at 14:09 Quote
R-M-R wrote:
rickyvic wrote:
Thank you guys.
A few notes:
bearings are perfect run smooth, so I guess you are right.
I checked the bearings and serviced them, nothing.
I serviced the bb
I will check if the rear axle is overtightened
Brakes dont rub (funny in the shimano hubs bike they rub pretty badly)

The slx hubs run a lot faster than any other bike, clearly maybe they have some very high end balls I dont know

I noticed the dt 240s run well too looking at my friends, at high speed my bike runs very fast and faster than most people (another odd thing) meaning that this is a problem found at very low speed and under load.

Yes, Shimano hubs - when adjusted properly - are usually a little faster than cartridge bearing hubs, but we're talking less than 1% of your total power output.

It's not the bearings. Not the hub's driver mechanism. Probably not the BB, as even the worst BB shouldn't waste more than 10 or 15 watts and it will quickly wear itself to the point of play in the bearings, so you'll know it was the BB within a ride or two.

When you say you tried the same tires, are they definitely the same tires? For example, the ubiquitous Minions are available with everything from light and fast casings to DH double-ply casings. If you compared DH Minions to EXO Minions, that's your answer right there. Just want to eliminate the easy things first.

Could it be the bike? Maybe one bike has squishy pedaling kinematics and the other is much more efficient, or one bike has a more efficient riding position. For me, a bike with low anti-squat and a slack seat tube angle reduces my climbing pace considerably and it feels even worse.

Same tyres magic mary snakeskin and high roller exo rear on both, both are gt sanction pro same frame. They don't bob much with the lockout.

Either is the axles that create some friction or the grease as mentioned above. I am definitely ruling out BB, chain guide and pulleys. It is certainly the wheels. It feels like you are on a skate with the Shimano hubs they roll forever, dt feel like you have someone pulling you from behind, until you are over 30 km/h then they become crazy fast.

It could even be that hubs are defective and they create some friction at low speed (last resort).
flag rickyvic
Posted: Mar 20, 2019 at 14:13 Quote
englertracing wrote:
If you re read my post carefully,
I mention bearing grease and fill quantaties
Then i mention oil for the ratchet system,
The type hadley uses.
Did thoulsanss of miles with hadley in the dt swiss 36t ratchet, its appearance never changed.

Certainly I am looking into it but it is not too clear what you wrote. Thanks for your help so far
flag R-M-R
Posted: Mar 20, 2019 at 14:17 Quote
rickyvic wrote:
Same tyres magic mary snakeskin and high roller exo rear on both, both are gt sanction pro same frame. They don't bob much with the lockout.

Either is the axles that create some friction or the grease as mentioned above. I am definitely ruling out BB, chain guide and pulleys. It is certainly the wheels. It feels like you are on a skate with the Shimano hubs they roll forever, dt feel like you have someone pulling you from behind, until you are over 30 km/h then they become crazy fast.

It could even be that hubs are defective and they create some friction at low speed (last resort).

Hub friction should be most apparent at high speeds, when the hubs are rotating fastest. This doesn't sound like a hub problem.

How about drivetrain friction? I knew a racer who was losing over 10% power to a badly maintained drivetrain. This is something that will have a constant power loss, regardless of speed, so the relative power loss is greatest when air resistance and rolling resistance are low (i.e. at low speed).
flag rickyvic
Posted: Mar 20, 2019 at 14:32 Quote
R-M-R wrote:
rickyvic wrote:
Same tyres magic mary snakeskin and high roller exo rear on both, both are gt sanction pro same frame. They don't bob much with the lockout.

Either is the axles that create some friction or the grease as mentioned above. I am definitely ruling out BB, chain guide and pulleys. It is certainly the wheels. It feels like you are on a skate with the Shimano hubs they roll forever, dt feel like you have someone pulling you from behind, until you are over 30 km/h then they become crazy fast.

It could even be that hubs are defective and they create some friction at low speed (last resort).

Hub friction should be most apparent at high speeds, when the hubs are rotating fastest. This doesn't sound like a hub problem.

How about drivetrain friction? I knew a racer who was losing over 10% power to a badly maintained drivetrain. This is something that will have a constant power loss, regardless of speed, so the relative power loss is greatest when air resistance and rolling resistance are low (i.e. at low speed).

Tell me about it, a few months back during a race with 1500m climb and 6 stages I nearly had a heart attack due to this problem.

I had the drivetrain just serviced by a mechanic, didn't change the situation.
flag englertracing
O+
Posted: Mar 20, 2019 at 15:10 Quote
rickyvic wrote:
englertracing wrote:
If you re read my post carefully,
I mention bearing grease and fill quantaties
Then i mention oil for the ratchet system,
The type hadley uses.
Did thoulsanss of miles with hadley in the dt swiss 36t ratchet, its appearance never changed.

Certainly I am looking into it but it is not too clear what you wrote. Thanks for your help so far


Ill try again,
shitty enduro bearings filled with shitty grease roll like shit,

taking bearings apart cleaning them with solvent, and compressed air untill no grease is left and refilling 1/4 full with ceramicspeed or kluber lds18 can lead to faster rolling, but is a total pain in the ass, especially if the bearings are on their way out in the first place and pretty much not worth it especially if the bearings are enduro garbage.

best choice is to order the bearing from a bearing house that can get NTN brand japanese bearings, so say you use 6902 bearing, order an NTN 6902LLB
THE LLB means low drag non contact shields, as opposed to 2rs, vv, zz, llu, or llh shields among others.

If you have nothing better to do you can pop them open and switch to fancy grease like ceramicspeed or kluber lds but, you might bend a shield, and its a total pain in the ass, do not recommend but have done it with good results

I use hadley hub oil, the company TRIFLOW, custom makes teflon oil for the hub manufacturer HADLEY.
I put this HADLEY branded TRIFLOW teflon oil into the ratchet mechanism of the DT SWISS instead of GREASE, and it lowers the free hub drag. DID not notice any wear over thousands of miles.

the DT18t and 36t drives are quite robust, and I have substituted Hadley oil into much more fragile systems with zero issues.

does that make sense now?
flag R-M-R
Posted: Mar 20, 2019 at 15:10 Quote
Try to arrange a blind test with your friend's wheels. Your friend will install a wheelset without telling you which it is. DO NOT LOOK AT THE WHEELS. Cover them with a blanket, then remove only when you start riding. See if you can tell the difference.

I'm starting to think this is a placebo effect that's based on your perception of the hubs; if so, the actual difference in power and speed may be nearly zero.
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